Timeline of the far future

{{Short description|Scientific projections regarding the far future}} {{Featured list}} {{Pp-pc|small=yes}} {{Use dmy dates|date=January 2021}} {{CS1 config|display-authors=4}}

[[File:Red Giant Earth warm.jpg|thumb|upright=1.4|alt=A dark gray and red sphere representing the Earth lies against a black background to the right of an orange circular object representing the Sun|Artist's concept of the Earth 5–7.5 billion years from now, when the Sun has become a red giant]]

While the future cannot be predicted with certainty, present understanding in various scientific fields allows for the prediction of some far-future events, if only in the broadest outline.<ref name="NYT-20230502">{{Cite news |last=Overbye |first=Dennis |author-link=Dennis Overbye |date=2 May 2023 |title=Who Will Have the Last Word on the Universe? – Modern science suggests that we and all our achievements and memories are destined to vanish like a dream. Is that sad or good? |url=https://www.nytimes.com/2023/05/02/science/end-of-universe.html |url-status=live |archive-url=https://web.archive.org/web/20230506052917/https://www.nytimes.com/2023/05/02/science/end-of-universe.html |archive-date=6 May 2023 |access-date=2 May 2023 |work=The New York Times}}</ref><ref>{{Cite book |title=Deep Time Reckoning |url=https://mitpress.mit.edu/9780262539265/deep-time-reckoning/ |access-date=14 August 2022 |series=One Planet |date=22 September 2020 |publisher=MIT Press |isbn=978-0-262-53926-5 |language=en-US}}</ref><ref>{{Cite book |last=Rescher |first=Nicholas |author-link=Nicholas Rescher |title=Predicting the future: An introduction to the theory of forecasting |date=1998 |publisher=State University of New York Press |isbn=978-0-7914-3553-3}}</ref><ref>{{Cite journal |last1=Adams |first1=Fred C. |last2=Laughlin |first2=Gregory |date=1 April 1997 |title=A dying universe: the long-term fate and evolution of astrophysical objects |url=https://cds.cern.ch/record/318436/files/9701131.pdf |journal=Reviews of Modern Physics |volume=69 |issue=2 |pages=337–372 |arxiv=astro-ph/9701131 |bibcode=1997RvMP...69..337A |doi=10.1103/RevModPhys.69.337 |issn=0034-6861 |s2cid=12173790 |archive-url=https://web.archive.org/web/20180727015521/https://cds.cern.ch/record/318436/files/9701131.pdf |archive-date=27 July 2018 |access-date=10 October 2021|author-link1=Fred Adams|author-link2=Gregory P. Laughlin}}</ref> These fields include astrophysics, which studies how planets and stars form, interact and die; particle physics, which has revealed how matter behaves at the smallest scales; evolutionary biology, which studies how life evolves over time; plate tectonics, which shows how continents shift over millennia; and sociology, which examines how human societies and cultures evolve.

These timelines begin at the start of the 4th millennium in 3001 CE, and continue until the furthest and most remote reaches of future time. They include alternative future events that address unresolved scientific questions, such as whether humans will become extinct, whether the Earth survives when the Sun expands to become a red giant and whether proton decay will be the eventual end of all matter in the universe.

== Earth, the Solar System, and the universe == {{See also|Formation and evolution of the Solar System|List of future astronomical events}}

All projections of the future of Earth, the Solar System and the universe must account for the second law of thermodynamics, which states that entropy, or a loss of the energy available to do work, must rise over time.<ref name="Nave"/> Stars will eventually exhaust their supply of hydrogen fuel via fusion and burn out. The Sun will likely expand sufficiently to overwhelm most of the inner planets (Mercury, Venus, and possibly Earth) but not the giant planets, including Jupiter and Saturn. Afterwards, the Sun will be reduced to the size of a white dwarf, and the outer planets and their moons will continue to orbit this diminutive solar remnant. This future situation may be similar to the white dwarf star MOA-2010-BLG-477L and the Jupiter-sized exoplanet orbiting it.<ref name="NAT-20211013">{{Cite journal |last1=Blackman |first1=J. W. |last2=Beaulieu |first2=J. P. |last3=Bennett |first3=D. P. |last4=Danielski |first4=C. |last5=Alard |first5=C. |last6=Cole |first6=A. A. |last7=Vandorou |first7=A. |last8=Ranc |first8=C. |last9=Terry |first9=S. K. |last10=Bhattacharya |last11=Bond |first11=I. |last12=Bachelet |first12=E. |last13=Veras |first13=D. |last14=Koshimoto |first14=N. |last15=Batista |first15=V. |date=13 October 2021 |title=A Jovian analogue orbiting a white dwarf star |url=https://www.nature.com/articles/s41586-021-03869-6 |journal=Nature |volume=598 |issue=7880 |pages=272–275 |arxiv=2110.07934 |bibcode=2021Natur.598..272B |doi=10.1038/s41586-021-03869-6 |pmid=34646001 |s2cid=238860454 |access-date=14 October 2021 |first16=J. B. |last16=Marquette}}</ref><ref name="KO-20211013">{{Cite news |last1=Blackman |first1=Joshua |last2=Bennett |first2=David |last3=Beaulieu |first3=Jean-Philippe |date=13 October 2021 |title=A Crystal Ball Into Our Solar System's Future – Giant Gas Planet Orbiting a Dead Star Gives Glimpse Into the Predicted Aftermath of our Sun's Demise |url=https://keckobservatory.org/white-dwarf-system/ |access-date=14 October 2021 |work=Keck Observatory}}</ref><ref name="NYT-20211013">{{Cite news |last=Ferreira |first=Becky |date=13 October 2021 |title=Astronomers Found a Planet That Survived Its Star's Death – The Jupiter-size planet orbits a type of star called a white dwarf, and hints at what our solar system could be like when the Sun burns out. |url=https://www.nytimes.com/2021/10/13/science/white-dwarf-planet.html |url-access=limited |archive-url=https://ghostarchive.org/archive/20211228/https://www.nytimes.com/2021/10/13/science/white-dwarf-planet.html |archive-date=28 December 2021 |access-date=14 October 2021 |work=The New York Times}}{{cbignore}}</ref>

Long after the death of the Solar System, physicists expect that matter itself will eventually disintegrate under the influence of radioactive decay, as even the most stable materials break apart into subatomic particles.<ref name="dying"/> Current data suggest that the universe has a flat geometry (or very close to flat) and will therefore not collapse in on itself after a finite time.<ref name="Komatsu"/> This infinite future could allow for the occurrence of massively improbable events, such as the formation of Boltzmann brains or spontaneous inflation triggering a new Big Bang.<ref name="linde"/><ref name="carroll and chen"/>

'''Keys''' {| class="wikitable" |- | style="background: lavender;" | 16px|alt=Astronomy and astrophysics|Astronomy and astrophysics | Astronomy and astrophysics |- | style="background: #f0dc82;" | 16px|alt=Geology and planetary science|Geology and planetary science | Geology and planetary science |- | style="background: #CEFF00;" | 16px|alt=Biology|Biology | Biology |- | style="background: #FFE4E1;" | 16px|alt=Particle physics|Particle physics | Particle physics |- | 16px|class=skin-invert-image|alt=Technology and culture|Technology and culture | Technology and culture |}

{| class="wikitable" style="width: 100%; margin-right: 0;" |- ! scope="col" | 16px|class=skin-invert-image|link=#Keys ! scope="col" | {{nowrap|Years from now}} ! scope="col" | Event |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 1,000 | Due to the lunar tides decelerating the Earth's rotation, the average length of a solar day will be {{frac|1|30}} of an SI second longer than it is today. To compensate, either a leap second will have to be added to the end of a day multiple times during each month, or one or more consecutive leap seconds will have to be added at the end of some or all months.<ref name="arxiv1106_3141"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 2,000 | As Earth's poles precess, Gamma Cephei replaces Polaris as the northern pole star.<ref>{{Cite web |last1=McClure |first1=Bruce |last2=Byrd |first2=Deborah |date=22 September 2021 |title=Gamma Cephei, aka Errai, a future North Star |url=https://earthsky.org/brightest-stars/gamma-cephei-errai-future-north-star/ |access-date=25 December 2021 |website=earthsky.org}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 1,000 – 10,000 | As one of the long-term effects of global warming, the Greenland ice sheet will have completely melted.<ref>{{Cite journal |last=Loutre |first=MF |date=1 April 1995 |title=Greenland Ice Sheet over the next 5000 years |url=https://www.webofscience.com/wos/woscc/full-record/WOS:A1995QR15300011 |journal=Geophysical Research Letters |language=en |volume=22 |issue=7 |pages=783–786 |bibcode=1995GeoRL..22..783L |doi=10.1029/95GL00362 |url-access=subscription |access-date=16 February 2025}}</ref> The melt rate will depend on the amount of carbon emissions in the air.<ref>{{Cite journal |last1=Bochow |first1=N |last2=Poltronieri |first2=A |last3=Robinson |first3=A |date=2023 |title=Overshooting the critical threshold for the Greenland ice sheet |journal=Nature |volume=622 |issue=7983 |pages=528–536 |doi=10.1038/s41586-023-06503-9 |pmid=37853149 |pmc=10584691 |bibcode=2023Natur.622..528B |hdl-access=free |hdl=10261/359219}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 10,000 | If a failure of the Wilkes Subglacial Basin "ice plug" in the next few centuries were to endanger the East Antarctic Ice Sheet, it would take up to this long to melt completely. Sea levels would rise 3 to 4 metres.<ref>{{Cite journal |last1=Mengel |first1=M. |last2=Levermann |first2=A. |date=4 May 2014 |title=Ice plug prevents irreversible discharge from East Antarctica |journal=Nature Climate Change |volume=4 |issue=6 |pages=451–455 |bibcode=2014NatCC...4..451M |doi=10.1038/nclimate2226}}</ref> One of the potential long-term effects of global warming, this is separate from the shorter-term threat to the West Antarctic Ice Sheet. |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 10,000 | If humans were extinct, Earth would be midway through a stable warm period with the next glacial period of the Quaternary glaciation due in 10,000 years, but if humans survived and did impact their planet, the greenhouse gas emissions would disrupt this natural cycle.<ref>{{Cite web |last=Shavit |first=Joseph |date=27 February 2025 |title=New research links ice ages to shifts in the Earth's orbit |url=https://www.thebrighterside.news/post/new-research-links-ice-ages-to-shifts-in-the-earths-orbit/ |access-date=28 February 2025 |website=The Brighter Side of News}}</ref> According to research, the carbon dioxide released from burning fossil fuels could cause the planet to skip glacial periods repeatedly for at least the next 500,000 years.<ref>{{Cite web |last=Schwaller |first=Fred |date=3 March 2025 |title=Our next ice age is due in 10,000 years, but there's a catch |url=https://www.dw.com/en/earths-next-ice-age-is-due-in-10000-years-but-theres-a-catch/a-71786018 |access-date=11 March 2025 |website=Deutsche Welle}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 10,000 – 1 million<ref name="prob" group="note">This represents the time by which the event will most probably have happened. It may occur randomly at any time from the present.</ref> | The red supergiant stars Betelgeuse and Antares will likely have exploded as supernovae. For a few months, the explosions should be easily visible on Earth in daylight.<ref name="hockey">{{Cite journal |last1=Hockey |first1=T. |last2=Trimble |first2=V. |year=2010 |title=Public reaction to a V = −12.5 supernova |journal=The Observatory |volume=130 |issue=3 |page=167 |bibcode=2010Obs...130..167H}}</ref><ref>{{Cite news |date=26 December 2019 |title=A giant star is acting strange, and astronomers are buzzing |url=https://www.nationalgeographic.com/science/2019/12/betelgeuse-is-acting-strange-astronomers-are-buzzing-about-supernova/ |archive-url=https://web.archive.org/web/20210108042242/https://www.nationalgeographic.com/science/2019/12/betelgeuse-is-acting-strange-astronomers-are-buzzing-about-supernova/ |archive-date=8 January 2021 |access-date=15 March 2020 |work=National Geographic |language=en}}</ref><ref name="betel">{{Cite web |last=Sessions |first=Larry |date=29 July 2009 |title=Betelgeuse will explode someday |url=http://earthsky.org/brightest-stars/betelgeuse-will-explode-someday |url-status=live |archive-url=https://web.archive.org/web/20210523155715/https://earthsky.org/brightest-stars/betelgeuse-will-explode-someday/ |archive-date=23 May 2021 |access-date=16 November 2010 |publisher=EarthSky Communications, Inc}}</ref><ref>{{Cite journal |last1=Saio |first1=Hideyuki |last2=Nandal |first2=Devesh |last3=Meynet |first3=Georges |last4=Ekstöm |first4=Sylvia |date=2 June 2023 |title=The evolutionary stage of Betelgeuse inferred from its pulsation periods |journal=Monthly Notices of the Royal Astronomical Society |volume=526 |issue=2 |page=2765 |arxiv=2306.00287 |bibcode=2023MNRAS.526.2765S |doi=10.1093/mnras/stad2949 |doi-access=free}}</ref><ref name="Neuhäuser_et_al_2022">{{Cite journal |last1=Neuhäuser |first1=R. |last2=Torres |first2=G. |last3=Mugrauer |first3=M. |last4=Neuhäuser |first4=D. L. |last5=Chapman |first5=J. |last6=Luge |first6=D. |last7=Cosci |first7=M. |date=July 2022 |title=Colour evolution of Betelgeuse and Antares over two millennia, derived from historical records, as a new constraint on mass and age |journal=Monthly Notices of the Royal Astronomical Society |volume=516 |issue=1 |pages=693–719 |arxiv=2207.04702 |bibcode=2022MNRAS.516..693N |doi=10.1093/mnras/stac1969 |doi-access=free}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 11,700 | As Earth's poles precess, Vega, the fifth-brightest star in the sky, becomes the northern pole star.<ref>{{Cite web |last=Howell |first=Elizabeth |date=9 November 2018 |title=Vega: The North Star of the Past and the Future |url=https://www.space.com/21719-vega.html |access-date=25 December 2021 |website=Space.com |language=en}}</ref> Although Earth cycles through many different naked-eye northern pole stars, Vega is the brightest. |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 11,000–15,000 | By this point, halfway through Earth's precessional cycle, Earth's axial tilt will be mirrored, causing summer and winter to occur on opposite sides of Earth's orbit. This means that the seasons in the Southern Hemisphere will be less extreme than they are today, as it will face away from the Sun at Earth's perihelion and towards the Sun at aphelion; the seasons in the Northern Hemisphere will be more extreme, as it experiences more pronounced seasonal variation because of a higher percentage of land.<ref name="plait">{{Cite book |last=Plait |first=Phil |author-link=Phil Plait |title=Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing "Hoax" |title-link=Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing "Hoax" |date=2002 |publisher=John Wiley and Sons |isbn=978-0-471-40976-2 |pages=[https://archive.org/details/badastronomymisc00plai_621/page/n65 55]–56}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 15,000 | The oscillating tilt of Earth's poles will have moved the North African Monsoon far enough north to change the climate of the Sahara back into a tropical one such as it had 5,000–10,000 years ago.<ref name="tropicalsahara1">{{Cite web |last=Mowat |first=Laura |date=14 July 2017 |title=Africa's desert to become lush green tropics as monsoons MOVE to Sahara, scientists say |url=https://www.express.co.uk/news/world/828144/Climate-change-Africa-Sahel-Sahara-region-monsoon-rainfall-drought |url-status=live |archive-url=https://web.archive.org/web/20210308053332/https://www.express.co.uk/news/world/828144/Climate-change-Africa-Sahel-Sahara-region-monsoon-rainfall-drought |archive-date=8 March 2021 |access-date=23 March 2018 |website=Daily Express |language=en}}</ref><ref name="tropicalsahara2">{{Cite web |date=23 December 2015 |title=Orbit: Earth's Extraordinary Journey |url=http://mymultiplesclerosis.co.uk/btbb/gilf-kebir-the-great-barrier-nick-drake-wadi-bakht/ |url-status=usurped |archive-url=https://web.archive.org/web/20180714131638/https://mymultiplesclerosis.co.uk/btbb/gilf-kebir-the-great-barrier-nick-drake-wadi-bakht/ |archive-date=14 July 2018 |access-date=23 March 2018 |website=ExptU}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 17,000<ref name="prob" group="note"/> | The best-guess recurrence rate for a "civilization-threatening" supervolcanic eruption large enough to eject one teratonne (one trillion tonnes) of pyroclastic material.<ref>{{Cite journal |date=30 November 2017 |title='Super-eruption' timing gets an update – and not in humanity's favour |url=https://www.nature.com/articles/d41586-017-07777-6 |url-status=live |journal=Nature |language=en |volume=552 |issue=7683 |page=8 |doi=10.1038/d41586-017-07777-6 |pmid=32080527 |s2cid=4461626 |archive-url=https://web.archive.org/web/20210724104719/https://www.nature.com/articles/d41586-017-07777-6 |archive-date=24 July 2021 |access-date=28 August 2020|url-access=subscription }}</ref><ref>{{Cite news |last=Gabbatiss |first=Josh |date=30 November 2017 |title=Scientists predict a volcanic eruption that would destroy humanity could happen sooner than previously thought |url=https://www.independent.co.uk/news/science/volcano-super-eruption-apocalypse-wipe-out-life-human-kind-timeline-how-long-a8082006.html |url-status=live |archive-url=https://web.archive.org/web/20201109034621/http://www.independent.co.uk/news/science/volcano-super-eruption-apocalypse-wipe-out-life-human-kind-timeline-how-long-a8082006.html |archive-date=9 November 2020 |access-date=28 August 2020 |work=The Independent |language=en}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 25,000 | The northern polar ice cap of Mars could recede as the planet reaches a warming peak of its northern hemisphere during the c. 50,000-year perihelion precession aspect of its Milankovitch cycle.<ref>{{Cite journal |last=Schorghofer |first=Norbert |date=23 September 2008 |title=Temperature response of Mars to Milankovitch cycles |journal=Geophysical Research Letters |volume=35 |issue=18 |page=L18201 |article-number=2008GL034954 |bibcode=2008GeoRL..3518201S |doi=10.1029/2008GL034954 |s2cid=16598911}}</ref><ref>{{Cite book |last=Beech |first=Martin |title=Terraforming: The Creating of Habitable Worlds |date=2009 |publisher=Springer |pages=138–142 |bibcode=2009tchw.book.....B}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 36,000 | The small red dwarf Ross 248 will pass within 3.024 light-years of Earth, becoming the closest star to the Sun.<ref name="Matthews1993"/> It will recede after about 8,000 years, making first Alpha Centauri (again) and then Gliese 445 the nearest stars<ref name="Matthews1993"/> (see timeline). |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 50,000 | According to Berger and Loutre, the current interglacial period will end,<ref name="Berger2002"/> sending the Earth back into a glacial period of the Quaternary glaciation, regardless of the effects of anthropogenic global warming. However, according to more recent studies in 2016, anthropogenic climate change, if left unchecked, may delay this otherwise expected glacial period by as much as an additional 50,000 years, potentially skipping it entirely.<ref>{{Cite web |title=Human-made climate change suppresses the next ice age – Potsdam Institute for Climate Impact Research |url=https://www.pik-potsdam.de/en/news/latest-news/human-made-climate-change-suppresses-the-next-ice-age |url-status=live |archive-url=https://web.archive.org/web/20210107231215/https://www.pik-potsdam.de/en/news/latest-news/human-made-climate-change-suppresses-the-next-ice-age |archive-date=7 January 2021 |access-date=21 October 2020 |website=pik-potsdam.de}}</ref>

Niagara Falls will have eroded the remaining 32 km to Lake Erie and will therefore cease to exist.<ref name="Niagara Parks"/>

The many glacial lakes of the Canadian Shield will have been erased by post-glacial rebound and erosion.<ref>{{Cite book |last=Bastedo |first=Jamie |url=https://books.google.com/books?id=-KUfAQAAIAAJ |title=Shield Country: The Life and Times of the Oldest Piece of the Planet |date=1994 |publisher=Arctic Institute of North America of the University of Calgary |isbn=978-0-919034-79-2 |series=Komatik Series, ISSN 0840-4488 |volume=4 |page=202 |access-date=15 March 2020 |archive-url=https://web.archive.org/web/20201103224359/https://books.google.com/books?id=-KUfAQAAIAAJ |archive-date=3 November 2020 |url-status=live}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 50,000 | Due to lunar tides decelerating the Earth's rotation, a day on Earth is expected to be one SI second longer than it is today. To compensate, either a leap second will have to be added to the end of every day, or the length of the day will have to be officially lengthened by one SI second.<ref name="arxiv1106_3141"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 60,000 | It is possible that the current cooling trend might be interrupted by an interstadial phase (a warmer period), with the next glacial maximum of the Quaternary glaciation reached only in about 100 kyr AP.<ref name="auto">{{Cite journal |last1=Loutre |first1=MF |last2=Berger |first2=A |date=1 July 2000 |title=Future climatic changes: Are we entering an exceptionally long interglacial? |url=https://www.webofscience.com/wos/woscc/full-record/WOS:000087703900003 |journal=Climatic Change |language=en |volume=46 |issue=1–2 |pages=61–90 |bibcode=2000ClCh...46...61L |doi=10.1023/A:1005559827189 |access-date=25 February 2025|url-access=subscription }}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 100,000 | The proper motion of stars across the celestial sphere, which results from their movement through the Milky Way, renders many of the constellations unrecognizable.<ref name="Tapping 2005"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 100,000<ref name="prob" group="note"/> | The red hypergiant star VY Canis Majoris will likely have exploded in a supernova.<ref name="Monnier Tuthill Lopez 1999"/> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 100,000 | Native North American earthworms, such as Megascolecidae, will have naturally spread north through the United States Upper Midwest to the Canada–United States border, recovering from the Laurentide ice sheet glaciation (38°N to 49°N), assuming a migration rate of 10 metres per year, and that a possible renewed glaciation by this time has not prevented this.<ref>{{Cite book |last1=Schaetzl |first1=Randall J. |url=https://archive.org/details/soilsgenesisgeom00scha |title=Soils: Genesis and Geomorphology |last2=Anderson |first2=Sharon |date=2005 |publisher=Cambridge University Press |isbn=978-1-139-44346-3 |page=[https://archive.org/details/soilsgenesisgeom00scha/page/n120 105] |url-access=limited}}</ref> (However, humans have already introduced non-native invasive earthworms of North America on a much shorter timescale, causing a shock to the regional ecosystem.) |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 100,000 – 10 million<ref name="prob" group="note"/> | Cupid and Belinda, moons of Uranus, will likely have collided.<ref>{{Cite journal |last1=French |first1=Robert S. |last2=Showalter |first2=Mark R. |date=August 2012 |title=Cupid is doomed: An analysis of the stability of the inner uranian satellites |journal=Icarus |volume=220 |issue=2 |pages=911–921 |arxiv=1408.2543 |bibcode=2012Icar..220..911F |doi=10.1016/j.icarus.2012.06.031 |s2cid=9708287}}</ref> |- | style="background: #f0dc82;" | 16px|alt= Geology and planetary science|Geology and planetary science | 100,000<ref name=prob group=note/> | Earth will likely have undergone a supervolcanic eruption large enough to erupt {{Convert|400|km3|abbr=in}} of magma.<ref>{{cite web|title=Frequency, locations and sizes of super-eruptions |publisher=The Geological Society|url=https://www.geolsoc.org.uk/Education-and-Careers/Resources/Papers-and-Reports/~/media/shared/documents/education%20and%20careers/Super_eruptions.ashx|archive-url=https://web.archive.org/web/20130613170422/https://www.geolsoc.org.uk/Education-and-Careers/Resources/Papers-and-Reports/~/media/shared/documents/education%20and%20careers/Super_eruptions.ashx |access-date=2025-06-27 |archive-date=13 June 2013 }}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 100,000 | According to Berger and Loutre, the next glacial maximum of the Quaternary glaciation is expected to be the most intense, regardless of the effects of anthropogenic global warming.<ref name="auto"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | > 100,000 | As one of the long-term effects of global warming, ten percent of anthropogenic carbon dioxide will still remain in a stabilized atmosphere.<ref>{{Cite book |last=Archer |first=David |url=https://archive.org/details/longthawhowhuman00arch_317 |title=The Long Thaw: How Humans Are Changing the Next 100,000 Years of Earth's Climate |date=2009 |publisher=Princeton University Press |isbn=978-0-691-13654-7 |page=[https://archive.org/details/longthawhowhuman00arch_317/page/n135 123] |url-access=limited}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 250,000 | Kamaʻehuakanaloa (formerly Lōʻihi), the youngest volcano in the Hawaiian–Emperor seamount chain, will rise above the surface of the ocean and become a new volcanic island.<ref name="havo"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | {{Circa}} 300,000<ref name="prob" group="note"/> | At some point in the next few hundred thousand years, the Wolf–Rayet star WR 104 may explode in a supernova. There is a small chance that WR 104 is spinning fast enough to produce a gamma-ray burst (GRB), and an even smaller chance that such a GRB could pose a threat to life on Earth.<ref>{{Cite journal |last1=Tuthill |first1=Peter |author-link=Peter Tuthill (astronomer) |last2=Monnier |first2=John |last3=Lawrance |first3=Nicholas |last4=Danchi |first4=William |last5=Owocki |first5=Stan |last6=Gayley |first6=Kenneth |year=2008 |title=The Prototype Colliding-Wind Pinwheel WR 104 |journal=The Astrophysical Journal |volume=675 |pages=698–710 |arxiv=0712.2111 |bibcode=2008ApJ...675..698T |doi=10.1086/527286 |s2cid=119293391 |number=1}}</ref><ref>{{Cite web |last=Tuthill |first=Peter |author-link=Peter Tuthill (astronomer) |title=WR 104: Technical Questions |url=http://www.physics.usyd.edu.au/~gekko/pinwheel/tech_faq.html |url-status=live |archive-url=https://web.archive.org/web/20180403160554/http://www.physics.usyd.edu.au/~gekko/pinwheel/tech_faq.html |archive-date=3 April 2018 |access-date=20 December 2015 |website=physics.usyd.edu.au}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 500,000<ref name="prob" group="note"/> | Earth will likely have been hit by an asteroid of roughly 1 km in diameter, assuming that it is not averted.<ref name="Bostrom 2002"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 500,000 | The rugged terrain of Badlands National Park in South Dakota will have eroded completely.<ref>{{Cite web |title=Badlands National Park – Nature & Science – Geologic Formations |url=http://www.nps.gov/badl/naturescience/geologicformations.htm |archive-url=https://web.archive.org/web/20150215201841/http://www.nps.gov/badl/naturescience/geologicformations.htm |archive-date=15 February 2015 |access-date=21 May 2014 |website=nps.gov}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 600,000<ref name="prob" group="note"/> | The estimated time for the third super-eruption of the Toba supervolcano by this date. The first super-eruption occurred around 840,000 years ago, after 1.4 million years of magma input, whereas magma fed the second super-eruption at 75,000 years.<ref>{{Cite web |last=Fuge |first=Lauren |date=2 November 2021 |title=From the vault: Can we predict the next supervolcano eruption? |url=https://cosmosmagazine.com/earth/earth-sciences/can-we-predict-the-next-supervolcano-eruption/ |access-date=14 April 2025 |website=Cosmos}}</ref><ref>{{Cite web |date=2 November 2021 |title=Estimating Future Super-Eruptions at Toba Volcano |url=https://www.innovations-report.com/agriculture-environment/earth-sciences/the-silent-build-up-to-a-super-eruption/ |website=Innovations Report}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 1 million | Meteor Crater, a large impact crater in Arizona considered the "freshest" of its kind, will have worn away.<ref>{{Cite book |last=Landstreet |first=John D. |url=https://books.google.com/books?id=Ads1AQAAIAAJ |title=Physical Processes in the Solar System: An introduction to the physics of asteroids, comets, moons and planets |date=2003 |publisher=Keenan & Darlington |isbn=978-0-9732051-0-7 |page=121 |access-date=15 March 2020 |archive-url=https://web.archive.org/web/20201028100029/https://books.google.com/books?id=Ads1AQAAIAAJ |archive-date=28 October 2020 |url-status=live}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 1 million<ref name="prob" group="note"/> | Desdemona and Cressida, moons of Uranus, will likely have collided.<ref name="Uranus">{{Cite web |year=2017 |title=Uranus's colliding moons |url=http://www.astronomy.com/news/2017/09/uranus-colliding-moons |url-status=live |archive-url=https://web.archive.org/web/20210226103604/https://astronomy.com/news/2017/09/uranus-colliding-moons |archive-date=26 February 2021 |access-date=23 September 2017 |publisher=astronomy.com}}</ref>

The stellar system Eta Carinae will likely have exploded in a supernova.<ref>{{Cite web |date=24 February 2012 |title=Preview of a Forthcoming Supernova |url=https://www.nasa.gov/image-article/preview-of-forthcoming-supernova/ |access-date=22 April 2025 |website=nasa.gov}}</ref> |- | style="background: #f0dc82;" | 16px|alt= Geology and planetary science|Geology and planetary science | 1 million<ref name=prob group=note/> | Earth will likely have undergone a supervolcanic eruption large enough to erupt {{Convert|3200|km3|abbr=in}} of magma, an event comparable to the Toba supereruption 75,000 years ago.<ref>{{cite web|title=Frequency, locations and sizes of super-eruptions |publisher=The Geological Society|url=https://www.geolsoc.org.uk/Education-and-Careers/Resources/Papers-and-Reports/~/media/shared/documents/education%20and%20careers/Super_eruptions.ashx|archive-url=https://web.archive.org/web/20130613170422/https://www.geolsoc.org.uk/Education-and-Careers/Resources/Papers-and-Reports/~/media/shared/documents/education%20and%20careers/Super_eruptions.ashx |access-date=2025-06-27 |archive-date=13 June 2013 }}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 1.29 ± 0.04 million | The star Gliese 710 will pass as close as 0.051 parsecs ({{convert|0.1663|ly|AU|abbr=off|lk=on|disp=semicolon}})<ref>{{Cite journal |last1=de la Fuente Marcos |first1=Raúl |last2=de la Fuente Marcos |first2=Carlos |date=2020 |title=An Update on the Future Flyby of Gliese 710 to the Solar System Using Gaia EDR3: Slightly Closer and a Tad Later than Previous Estimates |journal=Research Notes of the AAS |volume=4 |issue=12 |page=222 |doi=10.3847/2515-5172/abd18d |doi-access=free}}</ref> to the Sun before moving away. This will gravitationally perturb members of the Oort cloud, a halo of icy bodies orbiting at the edge of the Solar System, thereafter raising the likelihood of a cometary impact in the inner Solar System.<ref name="gliese"/> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 2 million | The estimated time for the full recovery of coral reef ecosystems from human-caused ocean acidification if such acidification goes unchecked; the recovery of marine ecosystems after the acidification event that occurred about 65 million years ago took a similar length of time.<ref>{{Cite book |last=Goldstein |first=Natalie |url=https://books.google.com/books?id=-uYkEBl6CWYC |title=Global Warming |date=2009 |publisher=Infobase Publishing |isbn=978-0-8160-6769-5 |page=53 |quote=The last time acidification on this scale occurred (about 65 mya) it took more than 2 million years for corals and other marine organisms to recover; some scientists today believe, optimistically, that it could take tens of thousands of years for the ocean to regain the chemistry it had in preindustrial times. |access-date=15 March 2020 |archive-url=https://web.archive.org/web/20201107194742/https://books.google.com/books?id=-uYkEBl6CWYC |archive-date=7 November 2020 |url-status=live}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 2 million+ | The Grand Canyon will erode further, deepening slightly, but principally widening into a broad valley surrounding the Colorado River.<ref>{{Cite web |title=Grand Canyon – Geology – A dynamic place |url=https://www.nps.gov/grca/learn/nature/grca-geology.htm |url-status=live |archive-url=https://web.archive.org/web/20210425063106/https://www.nps.gov/grca/learn/nature/grca-geology.htm |archive-date=25 April 2021 |access-date=11 October 2020 |website=Views of the National Parks |publisher=National Park Service}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 2.7 million | The average orbital half-life of current centaurs, which are unstable because of gravitational interactions with the several outer planets.<ref name="Horner2004a">{{Cite journal |last1=Horner |first1=J. |last2=Evans |first2=N. W. |last3=Bailey |first3=M. E. |date=2004 |title=Simulations of the Population of Centaurs I: The Bulk Statistics |journal=Monthly Notices of the Royal Astronomical Society |volume=354 |issue=3 |pages=798–810 |arxiv=astro-ph/0407400 |bibcode=2004MNRAS.354..798H |doi=10.1111/j.1365-2966.2004.08240.x |s2cid=16002759 |doi-access=free}}</ref> See predictions for notable centaurs. |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 3 million | Due to tidal deceleration gradually slowing Earth's rotation, a day on Earth is expected to be one minute longer than it is today. To compensate, either a "leap minute" will have to be added to the end of every day, or the length of the day will have to be officially lengthened by one SI minute.<ref name="arxiv1106_3141"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 6 million | Estimated time for comet C/1999 F1 (Catalina), one of the longest-period comets known to return to the inner Solar System, after having travelled in its orbit out to its aphelion {{convert|66600|AU|ly|abbr=in}} from the Sun and back.<ref>{{Cite web |last=Horizons output |author-link=JPL Horizons On-Line Ephemeris System |title=Barycentric Osculating Orbital Elements for Comet C/1999 F1 (Catalina) |url=http://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=C/1999+F1 |url-status=live |archive-url=https://web.archive.org/web/20210309063913/https://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=C%2F1999+F1 |archive-date=9 March 2021 |access-date=7 March 2011}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 10 million | The Red Sea will flood the widening East African Rift valley, causing a new ocean basin to divide the continent of Africa<ref name="rift"/> and the African plate into the newly formed Nubian plate and the Somali plate.

The Indian plate will advance into Tibet by {{cvt|180|km}}. Nepali territory, whose boundaries are defined by the Himalayan peaks and the plains of India, will cease to exist.<ref>{{Cite web |last=Bilham |first=Roger |date=November 2000 |title=NOVA Online {{!}} Everest {{!}} Birth of the Himalaya |url=https://www.pbs.org/wgbh/nova/everest/earth/birth.html |url-status=live |archive-url=https://web.archive.org/web/20210619030805/https://www.pbs.org/wgbh/nova/everest/earth/birth.html |archive-date=19 June 2021 |access-date=22 July 2021 |website=pbs.org}}</ref> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 10 million | The estimated time for the full recovery of biodiversity after a potential Holocene extinction, if it were on the scale of the five previous major extinction events.<ref>{{Cite journal |last1=Kirchner |first1=James W. |author-link1=James Kirchner |last2=Weil |first2=Anne |date=9 March 2000 |title=Delayed biological recovery from extinctions throughout the fossil record |journal=Nature |volume=404 |issue=6774 |pages=177–180 |bibcode=2000Natur.404..177K |doi=10.1038/35004564 |pmid=10724168 |s2cid=4428714}}</ref>

Even without a mass extinction, by this time most current species will have disappeared through the background extinction rate, with many clades gradually evolving into new forms.<ref>{{Cite book |last=Wilson |first=Edward O. |author-link=E. O. Wilson |url=https://books.google.com/books?id=FzPaB_6Pw4MC |title=The Diversity of Life |date=1999 |publisher=W.W. Norton & Company |isbn=978-0-393-31940-8 |page=216 |access-date=15 March 2020 |archive-url=https://web.archive.org/web/20201004022434/https://books.google.com/books?id=FzPaB_6Pw4MC |archive-date=4 October 2020 |url-status=live}}</ref><ref>{{Cite book |last=Wilson |first=Edward Osborne |author-link=Edward O. Wilson |url=https://books.google.com/books?id=VS7GeNorZE4C |title=The Diversity of Life |publisher=Penguin UK |year=1992 |isbn=978-0-14-193173-9 |location=London, England |publication-date=2001 |language=en-uk |chapter=The Human Impact |access-date=15 March 2020 |archive-url=https://web.archive.org/web/20200801131847/https://books.google.com/books?id=VS7GeNorZE4C |archive-date=1 August 2020 |url-status=live}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 15 million | An estimated 694 stars will have approached the Solar System to less than 5 parsecs. Of these, 26 have a good probability to come within {{convert|1.0|pc|ly|abbr=off|sigfig=2}} and 7 within {{convert|0.5|pc|ly|abbr=off|sigfig=2}}.<ref>{{Cite journal |last1=Bailer-Jones |first1=C. A. L. |last2=Rybizki |first2=J. |last3=Andrae |first3=R. |last4=Fouesnea |first4=M. |year=2018 |title=New stellar encounters discovered in the second Gaia data release |journal=Astronomy & Astrophysics |volume=616 |issue=37 |pages=A37 |arxiv=1805.07581 |bibcode=2018A&A...616A..37B |doi=10.1051/0004-6361/201833456 |s2cid=56269929}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 20 million | The Strait of Gibraltar will have closed due to subduction and a Ring of Fire will form in the Atlantic, similar to that in the Pacific.<ref>{{Cite journal |last1=Duarte |first1=João C. |last2=Riel |first2=Nicolas |last3=Rosas |first3=Filipe M. |last4=Popov |first4=Anton |last5=Schuler |first5=Christian |last6=Kaus |first6=Boris J.P. |date=13 February 2024 |title=Gibraltar subduction zone is invading the Atlantic |url=https://pubs.geoscienceworld.org/gsa/geology/article-abstract/52/5/331/634682/Gibraltar-subduction-zone-is-invading-the-Atlantic?redirectedFrom=fulltext |journal=Scientific Research |language=en |volume=52 |issue=5 |pages=331–335 |bibcode=2024Geo....52..331D |doi=10.1130/G51654.1 |access-date=17 January 2025|url-access=subscription }}</ref><ref>{{Cite web |last=Phiddian |first=Ellen |date=18 February 2024 |title=The Atlantic Ocean is growing – but only for now |work=Cosmos |url=https://cosmosmagazine.com/earth/earth-sciences/atlantic-ocean-shrinking-gibraltar/ |access-date=17 January 2025}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 30 million<ref name="prob" group="note"/> | Earth will likely have been hit by an asteroid of roughly 5 km in diameter, assuming that it is not averted.<ref>{{Cite web|date=6 April 2023|title=This is what would happen if scientists found an asteroid heading to Earth|website=Space.com |url=https://www.space.com/nasa-models-hypothetical-asteroid-impact-scenario|access-date=27 June 2025}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 50 million | The maximum estimated time before the moon Phobos collides with Mars.<ref name="Bills"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 50 million | According to Christopher Scotese, the movement of the San Andreas Fault will cause the Gulf of California to flood into the California Central Valley. This will form a new inland sea on the West Coast of North America, causing the current locations of Los Angeles and San Francisco in California to merge.<ref name="scotese"/>{{Failed verification|date=May 2022}} The Californian coast will begin to be subducted into the Aleutian Trench.<ref name="trench"/>

Africa's collision with Eurasia will close the Mediterranean basin and create a mountain range similar to the Himalayas.<ref name="medi"/>

The Appalachian Mountains peaks will have largely worn away,<ref>{{Cite encyclopedia |year=2011 |title=Geology |encyclopedia=Encyclopedia of Appalachia |publisher=University of Tennessee Press |url=http://www.encyclopediaofappalachia.com/category.php?rec=2 |access-date=21 May 2014 |archive-url=https://web.archive.org/web/20140521203455/http://www.encyclopediaofappalachia.com/category.php?rec=2 |archive-date=21 May 2014}}</ref> weathering at 5.7 Bubnoff units, although topography will actually rise as regional valleys deepen at twice this rate.<ref>{{Cite journal |last1=Hancock |first1=Gregory |last2=Kirwan |first2=Matthew |date=January 2007 |title=Summit erosion rates deduced from 10Be: Implications for relief production in the central Appalachians |url=http://pages.geo.wvu.edu/~kite/HancockKirwan2007SummitErosion.pdf |url-status=live |journal=Geology |volume=35 |issue=1 |page=89 |bibcode=2007Geo....35...89H |doi=10.1130/g23147a.1 |archive-url=https://web.archive.org/web/20181223151411/http://pages.geo.wvu.edu/~kite/HancockKirwan2007SummitErosion.pdf |archive-date=23 December 2018 |access-date=21 May 2014}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 50–60 million | The Canadian Rockies will have worn away to a plain, assuming a rate of 60 Bubnoff units.<ref>{{Cite book |last=Yorath |first=C. J. |title=Of rocks, mountains and Jasper: a visitor's guide to the geology of Jasper National Park |date=2017 |publisher=Dundurn Press |isbn=978-1-4597-3612-2 |page=30 |quote=[...] 'How long will the Rockies last?' [...] The numbers suggest that in about 50 to 60 million years the remaining mountains will be gone, and the park will be reduced to a rolling plain much like the Canadian prairies.}}</ref> The Southern Rockies in the United States are eroding at a somewhat slower rate.<ref>{{Cite journal |last1=Dethier |first1=David P. |last2=Ouimet |first2=W. |last3=Bierman |first3=P. R. |last4=Rood |first4=D. H. |last5=Balco |first5=G. |year=2014 |title=Basins and bedrock: Spatial variation in 10Be erosion rates and increasing relief in the southern Rocky Mountains, USA |url=http://noblegas.berkeley.edu/~balcs/pubs/Dethier_2014_Geology.pdf |url-status=live |journal=Geology |volume=42 |issue=2 |pages=167–170 |bibcode=2014Geo....42..167D |doi=10.1130/G34922.1 |archive-url=https://web.archive.org/web/20181223151250/http://noblegas.berkeley.edu/~balcs/pubs/Dethier_2014_Geology.pdf |archive-date=23 December 2018 |access-date=22 May 2014}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 50–400 million | The estimated time for Earth to naturally replenish its fossil fuel reserves.<ref>{{Cite book |last=Patzek |first=Tad W. |author-link=Tad Patzek |url=https://books.google.com/books?id=WNszUml_Wd4C |title=Biofuels, Solar and Wind as Renewable Energy Systems: Benefits and Risks |date=2008 |publisher=Springer |isbn=978-1-4020-8653-3 |editor-last=Pimentel |editor-first=David |chapter=Can the Earth Deliver the Biomass-for-Fuel we Demand? |access-date=15 March 2020 |archive-url=https://web.archive.org/web/20200801114937/https://books.google.com/books?id=WNszUml_Wd4C |archive-date=1 August 2020 |url-status=live}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 80 million | The Big Island will have become the last of the current Hawaiian Islands to sink beneath the surface of the ocean, while a more recently formed chain of "new Hawaiian Islands" will then have emerged in their place.<ref>{{Cite news |last=Perlman |first=David |author-link=David Perlman |date=14 October 2006 |title=Kiss that Hawaiian timeshare goodbye / Islands will sink in 80 million years |url=http://www.sfgate.com/news/article/Kiss-that-Hawaiian-timeshare-goodbye-Islands-2468202.php |url-status=live |archive-url=https://web.archive.org/web/20190417122705/https://www.sfgate.com/news/article/Kiss-that-Hawaiian-timeshare-goodbye-Islands-2468202.php |archive-date=17 April 2019 |access-date=21 May 2014 |work=San Francisco Chronicle}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 100 million<ref name="prob" group="note"/> | Earth will likely have been hit by an asteroid comparable in size to the one that triggered the K–Pg extinction 66 million years ago, assuming this is not averted.<ref name="kpg1"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 100 million | According to the Pangaea Proxima model created by Christopher R. Scotese, a new subduction zone will open in the Atlantic Ocean, and the Americas will begin to converge back toward Africa.<ref name="scotese"/>{{Failed verification|date=May 2022}}

Upper estimate for the lifespan of Saturn's rings in their current state.<ref>{{Cite book |last=Lang |first=Kenneth R. |url=https://archive.org/details/cambridgeguideto0000lang |title=The Cambridge Guide to the Solar System |date=2003 |publisher=Cambridge University Press |isbn=978-0-521-81306-8 |page=[https://archive.org/details/cambridgeguideto0000lang/page/329 329] |quote=[...] all the rings should collapse [...] in about 100 million years. |url-access=registration}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 110 million | The Sun's luminosity will have increased by one percent.<ref>{{Cite journal |last1=Schröder |first1=K.-P. |last2=Smith |first2=Robert Connon |year=2008 |title=Distant future of the Sun and Earth revisited |journal=Monthly Notices of the Royal Astronomical Society |volume=386 |issue=1 |pages=155–163 |arxiv=0801.4031 |bibcode=2008MNRAS.386..155S |doi=10.1111/j.1365-2966.2008.13022.x |s2cid=10073988 |doi-access=free}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 125 million | According to the Pangaea Proxima model created by Christopher R. Scotese, the Atlantic Ocean is predicted to stop widening and begin to shrink as the Mid-Atlantic Ridge seafloor spreading gives way to subduction. In this scenario, the mid-ocean ridge between South America and Africa will probably be subducted first; the Atlantic Ocean is predicted to narrow as a result of subduction beneath the Americas. The Indian Ocean is also predicted to be smaller due to northward subduction of oceanic crust into the Central Indian trench. Antarctica is expected to split in two and shift northwards, colliding with Madagascar and Australia, enclosing a remnant of the Indian Ocean, which Scotese calls the "Medi-Pangaean Sea".<ref>{{Cite journal |last=Scotese |first=Christopher R. |date=30 May 2021 |title=An Atlas of Phanerozoic Paleogeographic Maps: The Seas Come In and the Seas Go Out |journal=Annual Review of Earth and Planetary Sciences |volume=49 |issue=1 |pages=679–728 |bibcode=2021AREPS..49..679S |doi=10.1146/annurev-earth-081320-064052 |s2cid=233708826 |doi-access=free}}</ref><ref>{{Cite web |last=Scotese |first=Christopher R |date=2 February 2003 |title=The Atlantic Ocean begins to Close |url=http://www.scotese.com/future1.htm |url-status=live |archive-url=https://web.archive.org/web/20210426224100/http://scotese.com/future1.htm |archive-date=26 April 2021 |access-date=24 March 2012 |website=Paleomap Project}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 180 million | Due to the gradual slowing of Earth's rotation, a day on Earth will be one hour longer than it is today. To compensate, either a "leap hour" will have to be added to the end of every day, or the length of the day will have to be officially lengthened by one SI hour.<ref name="arxiv1106_3141"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 230 million | Prediction of the orbits of the Solar System's planets is impossible over timespans greater than this, due to the limitations of Lyapunov time.<ref name="hayes07">{{Cite journal |last=Hayes, Wayne B. |year=2007 |title=Is the Outer Solar System Chaotic? |journal=Nature Physics |volume=3 |issue=10 |pages=689–691 |arxiv=astro-ph/0702179 |bibcode=2007NatPh...3..689H |citeseerx=10.1.1.337.7948 |doi=10.1038/nphys728 |s2cid=18705038}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 240 million | From its present position, the Solar System completes one full orbit of the Galactic Center.<ref name="galyear"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 250 million | According to Christopher R. Scotese, due to the northward movement of the West Coast of North America, the coast of California will collide with Alaska.<ref name="scotese"/>{{Failed verification|date=May 2022}} |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 250–350 million | All the continents on Earth may fuse into a supercontinent.<ref name="scotese"/><ref name="Williams Nield 2007"/> Four potential arrangements of this configuration have been dubbed Amasia, Novopangaea, Pangaea Proxima and Aurica. This will likely result in a glacial period, lowering sea levels and increasing oxygen levels, further lowering global temperatures.<ref>{{Citation |last1=Calkin |first1=P. E. |title=Past glacial environments: sediments, forms, and techniques |date=1996 |volume=2 |pages=9–75 |postscript=. |editor-last=Menzies |editor-first=John |chapter=Global glaciation chronologies and causes of glaciation |publisher=Butterworth-Heinemann |isbn=978-0-7506-2352-0 |last2=Young |first2=G. M.}}</ref><ref name="PerryRussel1997">{{Cite book |last1=Perry |first1=Perry |title=Applied climatology: principles and practice |last2=Russel |first2=Thompson |publisher=Routledge |year=1997 |isbn=978-0-415-14100-0 |location=London, England |pages=127–128}}</ref> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | > 250 million | The supercontinent's formation, thanks to a combination of continentality increasing distance from the ocean, an increase in volcanic activity resulting in atmospheric CO2 at double current levels, increased interspecific competition, and a 2.5 percent increase in solar flux, is likely to trigger an extinction event comparable to the Great Dying 250 million years ago. Mammals in particular are unlikely to survive, assuming they still exist in their current forms by this point.<ref>{{Cite journal |last1=Farnsworth |first1=Alexander |last2=Lo |first2=Y. T. Eunice |last3=Valdes |first3=Paul J. |last4=Buzan |first4=Jonathan R. |last5=Mills |first5=Benjamin J. W. |last6=Merdith |first6=Andrew S. |last7=Scotese |first7=Christopher R. |last8=Wakeford |first8=Hannah R. |date=25 September 2023 |title=Climate extremes likely to drive land mammal extinction during next supercontinent assembly |url=https://eprints.whiterose.ac.uk/201952/16/s41561-023-01259-3.pdf |journal=Nature Geoscience |volume=16 |issue=10 |pages=901–908 |bibcode=2023NatGe..16..901F |doi=10.1038/s41561-023-01259-3}}</ref><ref name="swansong2">{{Cite journal |last1=O'Malley-James, Jack T. |last2=Greaves, Jane S. |last3=Raven, John A. |last4=Cockell, Charles S. |year=2014 |title=Swansong Biosphere II: The final signs of life on terrestrial planets near the end of their habitable lifetimes |journal=International Journal of Astrobiology |volume=13 |issue=3 |pages=229–243 |arxiv=1310.4841 |bibcode=2014IJAsB..13..229O |doi=10.1017/S1473550413000426 |s2cid=119252386}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 300 million | Due to a shift in the equatorial Hadley cells to roughly 40° north and south, the amount of arid land will increase by 25%.<ref name="swansong2"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 300–600 million | The estimated time for Venus's mantle temperature to reach its maximum. Then, over a period of about 100 million years, major subduction occurs and the crust is recycled.<ref name="Strom1994">{{Cite journal |last1=Strom |first1=Robert G. |last2=Schaber, Gerald G. |last3=Dawson, Douglas D. |date=25 May 1994 |title=The global resurfacing of Venus |url=https://zenodo.org/record/1231347 |url-status=live |journal=Journal of Geophysical Research |volume=99 |issue=E5 |pages=10899–10926 |bibcode=1994JGR....9910899S |doi=10.1029/94JE00388 |s2cid=127759323 |archive-url=https://web.archive.org/web/20200916233329/https://zenodo.org/record/1231347 |archive-date=16 September 2020 |access-date=6 September 2018}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 350 million | According to the extroversion model first developed by Paul F. Hoffman, subduction ceases in the Pacific Ocean basin.<ref name="Williams Nield 2007"/><ref>{{Cite journal |last=Hoffman |first=Paul F. |date=November 1992 |title=Rodinia to Gondwanaland to Pangea to Amasia: alternating kinematics of supercontinental fusion |url=https://journals.lib.unb.ca/index.php/ag/article/view/1870/2234 |journal=Atlantic Geology |volume=28 |issue=3 |page=284 |doi=10.4138/1870 |doi-access=free}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 400–500 million | The supercontinent (Pangaea Proxima, Novopangaea, Amasia, or Aurica) will likely have rifted apart.<ref name="Williams Nield 2007"/> This will likely result in higher global temperatures, similar to the Cretaceous period.<ref name="PerryRussel1997"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 500 million<ref name="prob" group="note"/> | The estimated time until a gamma-ray burst, or massive, hyperenergetic supernova, occurs within 6,500 light-years of Earth; close enough for its rays to affect Earth's ozone layer and potentially trigger a mass extinction, assuming the hypothesis is correct that a previous such explosion triggered the Ordovician–Silurian extinction event. However, the supernova would have to be precisely oriented relative to Earth to have such effect.<ref name="natgeo"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 600 million | Tidal acceleration moves the Moon far enough from Earth that total solar eclipses are no longer possible.<ref name="600mil"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 500–600 million | The Sun's increasing luminosity begins to disrupt the carbonate–silicate cycle; higher luminosity increases weathering of surface rocks, which traps carbon dioxide in the ground as carbonate. As water evaporates from the Earth's surface, rocks harden, causing plate tectonics to slow and eventually stop once the oceans evaporate completely. With less volcanism to recycle carbon into the Earth's atmosphere, carbon dioxide levels begin to fall.<ref name="swansong">{{Cite journal |last1=O'Malley-James, Jack T. |last2=Greaves, Jane S. |last3=Raven, John A. |last4=Cockell, Charles S. |year=2012 |title=Swansong Biospheres: Refuges for life and novel microbial biospheres on terrestrial planets near the end of their habitable lifetimes |journal=International Journal of Astrobiology |volume=12 |issue=2 |pages=99–112 |arxiv=1210.5721 |bibcode=2013IJAsB..12...99O |doi=10.1017/S147355041200047X |s2cid=73722450}}</ref> By this time, carbon dioxide levels will fall to the point at which {{C3}} photosynthesis is no longer possible. All plants that use {{C3}} photosynthesis (roughly 99 percent of present-day species) will die.<ref name="Heath Doyle 2009"/> The extinction of {{C3}} plant life is likely to be a long-term decline rather than a sharp drop. It is likely that plant groups will die one by one well before the critical carbon dioxide level is reached. The first plants to disappear will be {{C3}} herbaceous plants, followed by deciduous forests, evergreen broad-leaf forests, and finally evergreen conifers.<ref name="swansong2"/>

However, a 2024 paper by RJ Graham et al. argues that silicate weathering is far less temperature-dependent than initially thought, and that falling carbon dioxide levels are unlikely to lead to the death of life on Earth.<ref name="graham2024">{{Cite journal |last=Graham |first=R. J. |last2=Halevy |first2=Itay |last3=Abbot |first3=Dorian |name-list-style=and |date=25 November 2024 |title=Substantial Extension of the Lifetime of the Terrestrial Biosphere |journal=The Planetary Science Journal |volume=5 |page=255 |arxiv=2409.10714 |bibcode=2024PSJ.....5..255G |doi=10.3847/PSJ/ad7856 |doi-access=free |number=11}}</ref> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 500–800 million | As Earth begins to warm and carbon dioxide levels fall, plants—and, by extension, animals—could survive longer by evolving other strategies such as requiring less carbon dioxide for photosynthetic processes, becoming carnivorous, adapting to desiccation, or associating with fungi. These adaptations are likely to appear near the beginning of the moist greenhouse.<ref name="swansong2"/> The decrease in plant life will result in less oxygen in the atmosphere, allowing for more DNA-damaging ultraviolet radiation to reach the surface. The rising temperatures will increase chemical reactions in the atmosphere, further lowering oxygen levels. Plant and animal communities become increasingly sparse and isolated as the Earth becomes more barren. Flying animals would be better off because of their ability to travel large distances looking for cooler temperatures.<ref name="WardBrownlee2003">{{Cite book |last1=Ward |first1=Peter D. |author-link1=Peter Ward (paleontologist) |title=Rare earth: why complex life is uncommon in the universe |last2=Brownlee |first2=Donald |author-link2=Donald E. Brownlee |date=2003 |publisher=Copernicus |isbn=978-0-387-95289-5 |location=New York |pages=117–128}}</ref> Many animals may be driven to the poles or possibly underground. These creatures would become active during the polar night and aestivate during the polar day due to the intense heat and radiation. Much of the land would become a barren desert, and plants and animals would primarily be found in the oceans.<ref name="WardBrownlee2003"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 500–800 million | As pointed out by Peter Ward and Donald Brownlee in their book ''The Life and Death of Planet Earth'', according to NASA Ames scientist Kevin Zahnle, this is the earliest time for plate tectonics to eventually stop, due to the gradual cooling of the Earth's core, which could potentially turn the Earth back into a water world. This would, in turn, likely cause the extinction of Earth's remaining land life.<ref name="WardBrownlee2003"/> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 800–900 million | Carbon dioxide levels will fall to the point at which {{C4}} photosynthesis is no longer possible.<ref name="Heath Doyle 2009"/> Without plant life to recycle oxygen in the atmosphere, free oxygen and the ozone layer will disappear from the atmosphere allowing for intense levels of deadly UV light to reach the surface. Animals in food chains that were dependent on live plants will disappear shortly afterward.<ref name="swansong2"/> At most, animal life could survive about 3 to 100 million years after plant life dies out. Extinction will start with large animals, then smaller animals and flying creatures, then amphibians, followed by reptiles and, finally, invertebrates.<ref name="swansong"/> In the book ''The Life and Death of Planet Earth'', authors Peter D. Ward and Donald Brownlee state that some animal life may be able to survive in the oceans. Eventually, however, all multicellular life will die out.<ref name="bd2_6_1665"/> The first sea animals to go extinct will be large fish, followed by small fish and then, finally, invertebrates.<ref name="swansong"/> The last animals to go extinct will be animals that do not depend on living plants, such as termites, or those near hydrothermal vents, such as worms of the genus ''Riftia''.<ref name="swansong2"/> The only life left on the Earth after this will be single-celled organisms. |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 1 billion<ref name="shortscale" group="note">Units are short scale.</ref> | 27% of the ocean's mass will have been subducted into the mantle. If this were to continue uninterrupted, it would reach an equilibrium where 65% of present-day surface water would be subducted.<ref name="hess5_4_569"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 1 billion | By this point, the Sagittarius Dwarf Spheroidal Galaxy will have been completely consumed by the Milky Way.<ref name="Nature">{{Cite journal |last1=Antoja |first1=T. |last2=Helmi |first2=A. |last3=Romero-Gómez |first3=M. |last4=Katz |first4=D. |last5=Babusiaux |first5=C. |last6=Drimmel |first6=R. |last7=Evans |first7=D. W. |last8=Figueras |first8=F. |last9=Poggio |first9=E. |last10=Reylé |first10=C. |last11=Robin |first11=A. C. |last12=Seabroke |first12=G. |last13=Soubiran |first13=C. |date=19 September 2018 |title=A dynamically young and perturbed Milky Way disk |url=https://www.nature.com/articles/s41586-018-0510-7 |journal=Nature |volume=561 |issue=7723 |pages=360–362 |arxiv=1804.10196 |bibcode=2018Natur.561..360A |doi=10.1038/s41586-018-0510-7 |pmid=30232428 |s2cid=52298687 }}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 1.1 billion | The Sun's luminosity will have increased by 10%, causing Earth's surface temperatures to reach an average of around {{cvt|320|K|C F}}. The atmosphere will become a "moist greenhouse", resulting in a runaway evaporation of the oceans.<ref name="swansong"/><ref name="mnras386_1"/> This would cause plate tectonics to stop completely, if not already stopped before this time.{{sfn|Brownlee|2010|p=95}} Pockets of water may still be present at the poles, allowing abodes for simple life.{{sfn|Brownlee|2010|p=[https://books.google.com/books?id=M8NwTYEl0ngC&pg=PA79 79]}}<ref name="pressure"/> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt=Biology|Biology | 1.2 billion | High estimate until all plant life dies out, assuming some form of photosynthesis is possible despite extremely low carbon dioxide levels. If this is possible, rising temperatures will make any animal life unsustainable from this point on.<ref name="nature">{{Cite journal |last1=Caldeira |first1=Ken |last2=Kasting |first2=James F. |year=1992 |title=The life span of the biosphere revisited |journal=Nature |volume=360 |issue=6406 |pages=721–723 |bibcode=1992Natur.360..721C |doi=10.1038/360721a0 |pmid=11536510 |s2cid=4360963}}</ref><ref name="tellus_b_52_1">{{Cite journal |last=Franck |first=S. |year=2000 |title=Reduction of biosphere life span as a consequence of geodynamics |journal=Tellus B |volume=52 |issue=1 |pages=94–107 |bibcode=2000TellB..52...94F |doi=10.1034/j.1600-0889.2000.00898.x}}</ref><ref name="grl28_9">{{Cite journal |last1=Lenton |first1=Timothy M. |last2=von Bloh |first2=Werner |year=2001 |title=Biotic feedback extends the life span of the biosphere |journal=Geophysical Research Letters |volume=28 |issue=9 |pages=1715–1718 |bibcode=2001GeoRL..28.1715L |doi=10.1029/2000GL012198 |doi-access=free}}</ref> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 1.3 billion | Eukaryotic life dies out on Earth due to carbon dioxide starvation. Only prokaryotes remain.<ref name="bd2_6_1665"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 1.5 billion | Callisto is captured into the mean-motion resonance of the other Galilean moons of Jupiter, completing the 1:2:4:8 chain. (Currently only Io, Europa and Ganymede participate in the 1:2:4 resonance.)<ref>{{Cite journal |last1=Lari |first1=Giacomo |last2=Saillenfest |first2=Melaine |last3=Fenucci |first3=Marco |date=2020 |title=Long-term evolution of the Galilean satellites: the capture of Callisto into resonance |url=https://www.aanda.org/articles/aa/full_html/2020/07/aa37445-20/aa37445-20.html |journal=Astronomy & Astrophysics |volume=639 |pages=A40 |arxiv=2001.01106 |bibcode=2020A&A...639A..40L |doi=10.1051/0004-6361/202037445 |s2cid=209862163 |access-date=1 August 2022}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 1.5–1.6 billion | The Sun's rising luminosity causes its circumstellar habitable zone to move outwards; as carbon dioxide rises in Mars's atmosphere, its surface temperature increases to levels akin to Earth during the ice age.<ref name="bd2_6_1665"/><ref name="mars"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 1.5–4.5 billion | Tidal acceleration moves the Moon far enough from the Earth to the point where it can no longer stabilize Earth's axial tilt. As a consequence, Earth's true polar wander becomes chaotic and extreme, leading to dramatic shifts in the planet's climate due to the changing axial tilt.<ref name="wander"/> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 1.6 billion | Lower estimate until all remaining life, which by now had been reduced to colonies of unicellular organisms in isolated microenvironments such as high-altitude lakes and caves, goes extinct.<ref name="swansong"/><ref name="bd2_6_1665"/>{{sfn|Adams|2008|pp=33–47}} |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 1.66–1.86 billion | Estimated time until plant life goes extinct if silicate weathering does not increase fast enough to deplete atmospheric carbon dioxide below the minimum for {{C4}} photosynthesis, and biosphere decline is instead driven by overheating past the upper limit of {{convert|338|K|C F}} documented for a symbiont of ''Dichanthelium lanuginosum''. If this happens, then the disappearance of other multicellular life on land will happen around the same time.<ref name="graham2024"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | < 2 billion | The first close passage of the Andromeda Galaxy and the Milky Way.<ref name="cox"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 2 billion | High estimate until the Earth's oceans evaporate if the atmospheric pressure were to decrease via the nitrogen cycle.<ref name="pnas106_24"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 2.55 billion | The Sun will have reached a maximum surface temperature of {{cvt|5820|K|C F}}. From then on, it will become gradually cooler while its luminosity will continue to increase.<ref name="mnras386_1"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 2.8 billion | Earth's surface temperature will reach around {{cvt|420|K|C F}}, even at the poles.<ref name="swansong"/>{{sfn|Adams|2008|pp=33–47}} |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 2.8 billion | High estimate until all remaining Earth life goes extinct.<ref name="swansong"/>{{sfn|Adams|2008|pp=33–47}} |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 3–4 billion | The Earth's core freezes if the inner core continues to grow in size, based on its current growth rate of {{cvt|1|mm}} in diameter per year.<ref name="ng4_264"/><ref name="compo"/><ref name="meadows 2007">{{Cite book |last=Meadows |first=A. J. |url=https://archive.org/details/futureuniverse00mead_163 |title=The Future of the Universe |date=2007 |publisher=Springer |isbn=978-1-85233-946-3 |pages=[https://archive.org/details/futureuniverse00mead_163/page/n87 81]–83 |url-access=limited}}</ref> Without its liquid outer core, Earth's magnetosphere shuts down,<ref name="magnet"/> and solar winds gradually deplete the atmosphere.<ref>{{Cite journal |last=Shlermeler |first=Quirin |date=3 March 2005 |title=Solar wind hammers the ozone layer |journal=News@nature |doi=10.1038/news050228-12}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | {{Circa}} 3 billion<ref name="prob" group="note"/> | There is a roughly 1-in-100,000 chance that the Earth will be ejected into interstellar space by a stellar encounter before this point, and a 1-in-300-billion chance that it will be both ejected into space and captured by another star around this point. If this were to happen, any remaining life on Earth could potentially survive for far longer if it survived the interstellar journey.{{sfn|Adams|2008|pp=33–44}} |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 3.3 billion<ref name="prob" group="note"/> | There is a roughly one percent chance that Jupiter's gravity may make Mercury's orbit so eccentric as to cross Venus's orbit by this time, sending the inner Solar System into chaos. Other possible scenarios include Mercury colliding with the Sun, being ejected from the Solar System, or colliding with Venus or Earth.<ref name="chaos"/><ref>{{Cite news |last=Shiga |first=David |date=23 April 2008 |title=Solar system could go haywire before the Sun dies |url=https://www.newscientist.com/article/dn13757-solar-system-could-go-haywire-before-the-sun-dies/ |work=New Scientist}}</ref>{{Obsolete source|reason=This source is from 2008, but the chance of this happening at this time is quite less in new study.|date=May 2026}} |- | style="background: #f0dc82;" | 16px|link=#Keys|alt= Geology and planetary science|Geology and planetary science | 3.5–4.5 billion | The Sun's luminosity will have increased by 35–40%, causing all water currently present in lakes and oceans to evaporate, if it had not done so earlier. The greenhouse effect caused by the massive, water-rich atmosphere will result in Earth's surface temperature rising to {{cvt|1400|K|C F}}, which is hot enough to melt some surface rock.{{sfn|Brownlee|2010|p=95}}<ref name="pnas106_24">{{Cite journal |last1=Li |first1=King-Fai |last2=Pahlevan |first2=Kaveh |last3=Kirschvink |first3=Joseph L. |last4=Yung |first4=Yuk L. |date=16 June 2009 |title=Atmospheric pressure as a natural climate regulator for a terrestrial planet with a biosphere |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=106 |issue=24 |pages=9576–9579 |bibcode=2009PNAS..106.9576L |doi=10.1073/pnas.0809436106 |pmc=2701016 |pmid=19487662 |doi-access=free}}</ref><ref name="guinan_ribas">{{Cite journal |last1=Guinan |first1=E. F. |last2=Ribas |first2=I. |year=2002 |editor-last=Montesinos |editor-first=Benjamin |editor2-last=Gimenez |editor2-first=Alvaro |editor3-last=Guinan |editor3-first=Edward F. |title=Our Changing Sun: The Role of Solar Nuclear Evolution and Magnetic Activity on Earth's Atmosphere and Climate |journal=ASP Conference Proceedings |volume=269 |pages=85–106 |bibcode=2002ASPC..269...85G}}</ref><ref name="icarus74">{{Cite journal |last=Kasting |first=James F. |date=June 1988 |title=Runaway and moist greenhouse atmospheres and the evolution of earth and Venus |url=https://zenodo.org/record/1253896 |url-status=live |journal=Icarus |volume=74 |issue=3 |pages=472–494 |bibcode=1988Icar...74..472K |doi=10.1016/0019-1035(88)90116-9 |pmid=11538226 |archive-url=https://web.archive.org/web/20191207210741/https://zenodo.org/record/1253896 |archive-date=7 December 2019 |access-date=6 September 2018}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 4.32 billion | Due to the gradual slowing of Earth's rotation, a day on Earth will be twice as long as it is today. To compensate, either a "leap day" will have to be added to the end of every day, or the length of the day will have to be officially lengthened by one day.<ref name="arxiv1106_3141"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 4.5 billion | Mars reaches the same solar flux as that of the Earth when it first formed 4.5 billion years ago from today.<ref name="mars"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 5.4 billion | The Sun, having now exhausted its hydrogen supply, leaves the main sequence and begins evolving into a red giant.<ref name="Schroder 2008"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 6.5 billion | Mars reaches the same solar radiation flux as Earth today, after which it will suffer a similar fate to the Earth as described above.<ref name="mars"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 6.6 billion | The Sun may experience a helium flash, resulting in its core becoming as bright as the combined luminosity of all the stars in the Milky Way galaxy.<ref>{{Cite web |last=Taylor |first=David |title=The End Of The Sun |url=https://faculty.wcas.northwestern.edu/~infocom/The%20Website/end.html |url-status=live |archive-url=https://web.archive.org/web/20210512065300/https://faculty.wcas.northwestern.edu/~infocom/The%20Website/end.html |archive-date=12 May 2021 |access-date=29 July 2021}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 7.5 billion | Earth and Mars may become tidally locked with the expanding red giant Sun.<ref name="mars"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 7.59 billion | The Earth and Moon are very likely destroyed by falling into the Sun, just before the Sun reaches the top of its red giant phase.<ref name="Schroder 2008"/><ref name="earthredgiantsun" group="note">See the 2001 paper by Rybicki, K. R. and Denis, C. However, according to the latest calculations, this happens with a very high degree of certainty.</ref> Before the final collision, the Moon possibly spirals below Earth's Roche limit, breaking into a ring of debris, most of which falls to the Earth's surface.<ref name="powell2007"/>

During this era, the Solar System's habitable zone will expand to have a range of 49.4 AU to 71.4 AU, reaching well into the Kuiper Belt.<ref name="Schroder 2008"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 7.9 billion | The Sun reaches the top of the red-giant branch of the Hertzsprung–Russell diagram, achieving its maximum radius of 256 times the present-day value.<ref name="Rybicki2001"/> In the process, Mercury, Venus and Earth are likely destroyed.<ref name="Schroder 2008"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 8 billion | The Sun becomes a carbon–oxygen white dwarf with about 54.05% of its present mass.<ref name="Schroder 2008"/><ref name="nebula"/><ref name="apj676_1_594"/><ref name="dwarf group note">{{harvnb|Kalirai |Hansen |Kelson |Reitzel |2008 |p=16}}. Based upon the weighted least-squares best fit with the initial mass equal to a solar mass.</ref> At this point, if the Earth survives, temperatures on the surface of the planet, as well as the other planets in the Solar System, will begin dropping rapidly, due to the white dwarf Sun emitting much less energy than it does today. |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 10 billion | The Andromeda Galaxy will have a 50% probability of having collided with the Milky Way, forming an elliptical galaxy dubbed "Milkomeda".<ref name="sawala"/> If the collision has occurred, there is also a small chance of the Solar System being ejected.<ref name="cox"/><ref name="Cain">{{Cite web |last=Cain |first=Fraser |year=2007 |title=When Our Galaxy Smashes into Andromeda, What Happens to the Sun? |url=http://www.universetoday.com/2007/05/10/when-our-galaxy-smashes-into-andromeda-what-happens-to-the-sun/ |url-status=live |archive-url=https://web.archive.org/web/20070517021426/http://www.universetoday.com/2007/05/10/when-our-galaxy-smashes-into-andromeda-what-happens-to-the-sun/ |archive-date=17 May 2007 |access-date=16 May 2007 |website=Universe Today}}</ref> The planets of the Solar System will almost certainly not be disturbed by these events.<ref>{{Cite web |date=31 May 2012 |title=NASA's Hubble Shows Milky Way is Destined for Head-On Collision |url=http://www.nasa.gov/mission_pages/hubble/science/milky-way-collide.html |url-status=live |archive-url=https://web.archive.org/web/20200430054838/https://www.nasa.gov/mission_pages/hubble/science/milky-way-collide.html |archive-date=30 April 2020 |access-date=13 October 2012 |website=NASA}}</ref><ref>{{Cite news |last=Dowd |first=Maureen |author-link=Maureen Dowd |date=29 May 2012 |title=Andromeda Is Coming! |url=https://www.nytimes.com/2012/05/30/opinion/dowd-andromeda-is-coming.html |url-status=live |archive-url=https://web.archive.org/web/20210308163232/https://www.nytimes.com/2012/05/30/opinion/dowd-andromeda-is-coming.html |archive-date=8 March 2021 |access-date=9 January 2014 |work=The New York Times |quote=[NASA's David Morrison] explained that the Andromeda-Milky Way collision would just be two great big fuzzy balls of stars and mostly empty space passing through each other harmlessly over the course of millions of years.}}</ref><ref name="milk"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | >22.3 billion | 22.3 billion years is the estimated time until the end of the universe in a Big Rip, assuming a model of dark energy with {{var|w}} = −1.5.<ref name="bigrip"/><ref>{{Cite web |last1=Siegel |first1=Ethan |title=Ask Ethan: Could The Universe Be Torn Apart In A Big Rip? |url=https://www.forbes.com/sites/startswithabang/2018/06/30/ask-ethan-could-the-universe-be-torn-apart-in-a-big-rip/ |url-status=live |archive-url=https://web.archive.org/web/20210802032741/https://www.forbes.com/sites/startswithabang/2018/06/30/ask-ethan-could-the-universe-be-torn-apart-in-a-big-rip/ |archive-date=2 August 2021 |access-date=26 January 2021 |website=Forbes}}</ref> If the density of dark energy is less than −1, then the universe's expansion will continue to accelerate and the observable universe will grow ever sparser. Around 200 million years before the Big Rip, galaxy clusters like the Local Group or the Sculptor Group will be destroyed; 60 million years before the Big Rip, all galaxies will begin to lose stars around their edges and will completely disintegrate in another 40 million years; three months before the Big Rip, star systems will become gravitationally unbound, and planets will fly off into the rapidly expanding universe; thirty minutes before the Big Rip, planets, stars, asteroids and even extreme objects like neutron stars and black holes will evaporate into atoms; one hundred zeptoseconds (10−19 seconds) before the Big Rip, atoms will break apart. Ultimately, once the Rip reaches the Planck scale, cosmic strings would be disintegrated as well as the fabric of spacetime itself. The universe would enter into a "rip singularity" when all non-zero distances become infinitely large. Whereas a "crunch singularity" involves all matter being infinitely concentrated, in a "rip singularity", all matter is infinitely spread out.<ref>{{Cite journal |last1=Caldwell |first1=Robert R. |last2=Kamionkowski, Marc |last3=Weinberg, Nevin N. |year=2003 |title=Phantom Energy and Cosmic Doomsday |journal=Physical Review Letters |volume=91 |issue=7 |article-number=071301 |arxiv=astro-ph/0302506 |bibcode=2003PhRvL..91g1301C |doi=10.1103/PhysRevLett.91.071301 |pmid=12935004 |s2cid=119498512}}</ref>

Observations of galaxy cluster speeds by the Chandra X-ray Observatory suggest that the value of {{var|w}} is c. −0.991, meaning the Big Rip is unlikely to occur.<ref name="chand"/> Meanwhile, more recent data (2018) from the Planck mission indicates the value of {{var|w}} to be c. −1.028 (&pm;0.031), pushing the earliest possible time of the Big Rip to approximately 200 billion years into the future.<ref name="plank"> {{cite journal |author1=The Planck Collaboration |title=Planck 2018 results. VI. Cosmological parameters |journal=Astronomy and Astrophysics |year=2020 |volume=641 |pages=A6 |doi=10.1051/0004-6361/201833910 |arxiv=1807.06209 |bibcode=2020A&A...641A...6P|s2cid=119335614 }}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 28 billion | Neptune's moon Triton falls through the planet's Roche limit, disintegrating into a planetary ring system similar to Saturn's.<ref name="Wang2025">{{cite journal |last1=Wang |first1=K. |last2=Zhang |first2=H. |last3=Li |first3=Y. |last4=Qiao |first4=L. |title=A Plausible Minimum Value of the Neptunian Tidal Dissipation Factor Estimated from Triton’s Astrometric Observations |journal=Solar System Research |volume=59 |issue=1 |pages=6–15 |doi=10.1134/S0038094624601440 |url=https://link.springer.com/article/10.1134/S0038094624601440 |date=2025-02-18 |access-date=2026-05-12|url-access=subscription }}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 50 billion | If the Earth and Moon are not engulfed by the Sun, by this time they will become tidally locked, with each showing only one face to the other.<ref name="tide1">{{Cite book |last1=Murray |first1=C. D. |url=https://books.google.com/books?id=aU6vcy5L8GAC&pg=PA184 |title=Solar System Dynamics |last2=Dermott |first2=S. F. |date=1999 |publisher=Cambridge University Press |isbn=978-0-521-57295-8 |page=184 |language=en |access-date=27 March 2016 |archive-url=https://web.archive.org/web/20200801121137/https://books.google.com/books?id=aU6vcy5L8GAC&pg=PA184 |archive-date=1 August 2020 |url-status=live |name-list-style=amp}}</ref><ref name="tide2">{{Cite book |last=Dickinson |first=Terence |author-link=Terence Dickinson |title=From the Big Bang to Planet X |date=1993 |publisher=Camden House |isbn=978-0-921820-71-0 |location=Camden East, Ontario |pages=79–81 |language=en}}</ref> Thereafter, the tidal action of the white dwarf Sun will extract angular momentum from the system, causing the lunar orbit to decay and the Earth's spin to accelerate.<ref name="canup_righter">{{Cite book |last1=Canup |first1=Robin M. |author-link1=Robin Canup |url=https://books.google.com/books?id=8i44zjcKm4EC&pg=PA176 |title=Origin of the Earth and Moon |last2=Righter |first2=Kevin |date=2000 |publisher=University of Arizona Press |isbn=978-0-8165-2073-2 |series=The University of Arizona space science series |volume=30 |pages=176–177 |access-date=27 March 2016 |archive-url=https://web.archive.org/web/20200801122840/https://books.google.com/books?id=8i44zjcKm4EC&pg=PA176 |archive-date=1 August 2020 |url-status=live}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 65 billion | The Moon may collide with the Earth or be torn apart to form an orbital ring due to the decay of its orbit, assuming the Earth and Moon have not already been destroyed.<ref>{{Cite web |last=Dorminey |first=Bruce |date=31 January 2017 |title=Earth and Moon May Be on Long-Term Collision Course |url=https://www.forbes.com/sites/brucedorminey/2017/01/31/earth-and-moon-may-be-on-long-term-collision-course/ |url-status=live |archive-url=https://web.archive.org/web/20170201080301/https://www.forbes.com/sites/brucedorminey/2017/01/31/earth-and-moon-may-be-on-long-term-collision-course/ |archive-date=1 February 2017 |access-date=11 February 2017 |website=Forbes}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 100 billion – 1 trillion | All the ≈47 galaxies<ref name="messier"/> of the Local Group will coalesce into a single large galaxy—an expanded "Milkomeda"/"Milkdromeda"; the last galaxies of the Local Group coalescing will mark the effective completion of its evolution.<ref name="dying"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 100–150 billion | The universe's expansion causes all galaxies beyond the former Local Group to disappear beyond the cosmic light horizon, removing them from the observable universe.<ref name="galaxy"/><ref name="Ord">{{Cite arXiv |eprint=2104.01191 |class=gr-qc |first=Toby |last=Ord |title=The Edges of Our Universe |date=5 May 2021}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 150 billion | The universe will have expanded by a factor of 6,000, and the cosmic microwave background will have cooled by the same factor to around {{val|4.5|e=-4|u=K}}. The temperature of the background will continue to cool in proportion to the expansion of the universe.<ref name="Ord"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 325 billion | The estimated time by which the expansion of the universe will have isolated all gravitationally bound structures within their own cosmological horizon. At this point, the universe will have expanded by a factor of more than 100 million from today, and even individual exiled stars will be isolated.<ref name=":0"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 800 billion | The expected time when the net light emission from the combined "Milkomeda" galaxy begins to decline as the red dwarf stars pass through their blue dwarf stage of peak luminosity.<ref name="bluedwarf"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1 trillion | A low estimate for the time until star formation ends in galaxies as galaxies are depleted of the gas clouds they need to form stars.<ref name="dying"/>

The universe's expansion, assuming a constant dark energy density, multiplies the wavelength of the cosmic microwave background by 1029, exceeding the scale of the cosmic light horizon and rendering its evidence of the Big Bang undetectable. However, it may still be possible to determine the expansion of the universe through the study of hypervelocity stars.<ref name="galaxy"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1.05 trillion | The estimated time by which the universe will have expanded by a factor of more than 1026, reducing the average particle density to less than one particle per cosmological horizon volume. Beyond this point, particles of unbound intergalactic matter are effectively isolated, and collisions between them cease to affect the future evolution of the universe.<ref name=":0">{{Cite journal |last1=Busha |first1=Michael T. |last2=Adams |first2=Fred C. |last3=Wechsler |first3=Risa H. |last4=Evrard |first4=August E. |date=20 October 2003 |title=Future Evolution of Structure in an Accelerating Universe |journal=The Astrophysical Journal |volume=596 |issue=2 |pages=713–724 |arxiv=astro-ph/0305211 |doi=10.1086/378043 |issn=0004-637X |s2cid=15764445|author-link2=Fred Adams}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1.4 trillion | The estimated time by which the cosmic background radiation cools to a floor temperature of 10−30 K and does not decline further. This residual temperature comes from horizon radiation, which does not decline over time.<ref name="Ord"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 2 trillion | The estimated time by which all objects beyond our former Local Group are redshifted by a factor of more than 1053. Even gamma rays that they emit are stretched so that their wavelengths are greater than the physical diameter of the horizon. The resolution time for such radiation will exceed the physical age of the universe.<ref>{{Cite journal |last1=Krauss |first1=Lawrence M. |author-link1=Lawrence Krauss |last2=Starkman |first2=Glenn D. |author-link2=Glenn D. Starkman |date=March 2000 |title=Life, The Universe, and Nothing: Life and Death in an Ever-Expanding Universe |journal=The Astrophysical Journal |volume=531 |issue=1 |pages=22–30 |arxiv=astro-ph/9902189 |bibcode=2000ApJ...531...22K |doi=10.1086/308434 |issn=0004-637X |s2cid=18442980}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 4 trillion | The estimated time until the red dwarf star Proxima Centauri, the closest star to the Sun today, at a distance of 4.25 light-years, leaves the main sequence and becomes a white dwarf.<ref>{{Cite journal |last1=Adams |first1=Fred C. |author-link1=Fred Adams |last2=Laughlin |first2=Gregory |author-link2=Gregory P. Laughlin |last3=Graves |first3=Genevieve J. M. |year=2004 |title=RED Dwarfs and the End of The Main Sequence |url=http://www.astroscu.unam.mx/rmaa/RMxAC..22/PDF/RMxAC..22_adams.pdf |url-status=live |journal=Revista Mexicana de Astronomía y Astrofísica, Serie de Conferencias |volume=22 |pages=46–49 |archive-url=https://web.archive.org/web/20181223151311/http://www.astroscu.unam.mx/rmaa/RMxAC..22/PDF/RMxAC..22_adams.pdf |archive-date=23 December 2018 |access-date=21 May 2016}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 10 trillion | The estimated time of peak habitability in the universe, unless habitability around low-mass stars is suppressed.<ref name="loeb_2016"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 12 trillion | The estimated time until the red dwarf star VB 10—as of 2016, the least-massive main-sequence star with an estimated mass of 0.075 {{Solar mass}}—runs out of hydrogen in its core and becomes a white dwarf.<ref name="S&T 22">{{Cite journal |date=November 1997 |title=Why the Smallest Stars Stay Small |journal=Sky & Telescope |issue=22}}</ref><ref>{{Cite journal |last1=Adams |first1=F. C. |author-link1=Fred Adams |last2=Bodenheimer |first2=P. |last3=Laughlin |first3=G. |author-link3=Gregory P. Laughlin |year=2005 |title=M dwarfs: planet formation and long term evolution |journal=Astronomische Nachrichten |volume=326 |issue=10 |pages=913–919 |bibcode=2005AN....326..913A |doi=10.1002/asna.200510440 |doi-access=free}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 30 trillion | The estimated time for stars (including the Sun) to undergo a close encounter with another star in local stellar neighborhoods. Whenever two stars (or stellar remnants) pass close to each other, their planets' orbits can be disrupted, potentially ejecting them from the system entirely. On average, the closer a planet's orbit to its parent star the longer it takes to be ejected in this manner, because it is gravitationally more tightly bound to the star.<ref name="strip"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 100 trillion | A high estimate for the time by which normal star formation ends in galaxies.<ref name="dying"/> This marks the transition from the Stelliferous Era to the Degenerate Era; with too little free hydrogen to form new stars, all remaining stars slowly exhaust their fuel and die.<ref name="five ages"/> By this time, the universe will have expanded by a factor of approximately 102554.<ref name=":0"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 110–120 trillion | The time by which all stars in the universe will have exhausted their fuel (the longest-lived stars, low-mass red dwarfs, have lifespans of roughly 10–20 trillion years).<ref name="dying"/> After this point, the stellar-mass objects remaining are stellar remnants (white dwarfs, neutron stars, black holes) and brown dwarfs.

Collisions between brown dwarfs will create new red dwarfs on a marginal level: on average, about 100 stars will shine in what was once "Milkomeda". Collisions between stellar remnants will create occasional supernovae.<ref name="dying"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1015 (1 quadrillion) | The estimated time until stellar close encounters detach all planets in star systems (including the Solar System) from their orbits.<ref name="dying"/>

By this point, the black dwarf that was once the Sun will have cooled to {{cvt|5|K|C F}}.<ref name="five degs"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1019 to 1020 (10–100 quintillion) | The estimated time until 90–99% of brown dwarfs and stellar remnants (including the Sun) are ejected from galaxies. When two objects pass close enough to each other, they exchange orbital energy, with lower-mass objects tending to gain energy. Through repeated encounters, the lower-mass objects can gain enough energy in this manner to be ejected from their galaxy. This process eventually causes "Milkomeda"/"Milkdromeda" to eject the majority of its brown dwarfs and stellar remnants.<ref name="dying"/><ref name="five ages pp85–87"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1020 (100 quintillion) | The estimated time until the Earth collides with the black dwarf Sun due to the decay of its orbit via emission of gravitational radiation,<ref name="dyson"/> if the Earth is not ejected from its orbit by a stellar encounter or engulfed by the Sun during its red giant phase.<ref name="dyson"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1023 (100 sextillion) | Around this timescale, most stellar remnants and other objects are ejected from the remains of their galactic cluster.<ref>{{Cite web |last=Baez |first=John C. |author-link=John C. Baez |date=7 February 2016 |title=The End of the Universe |url=http://math.ucr.edu/home/baez/end.html |url-status=live |archive-url=https://web.archive.org/web/20090530050623/http://math.ucr.edu/home/baez/end.html |archive-date=30 May 2009 |access-date=13 February 2021 |website=math.ucr.edu}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1030 (1 nonillion) | The estimated time until most or all of the remaining 1–10% of stellar remnants not ejected from galaxies fall into their galaxies' central supermassive black holes. By this point, with binary stars having fallen into each other, and planets into their stars, via emission of gravitational radiation, only solitary objects (stellar remnants, brown dwarfs, ejected planetary-mass objects, black holes) will remain in the universe.<ref name="dying"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 2×1036 (2 undecillion) | The estimated time for all nucleons in the observable universe to decay, if the hypothesized proton half-life takes its smallest possible value (8.2 × 1033 years).<ref name="proton"/><ref name="half-life" group="note">Around 264 half-lives. Tyson et al. employ the computation with a different value for half-life.</ref> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 1036–1038 (1–100 undecillion) | The estimated time for all remaining planets and stellar-mass objects, including the Sun, to disintegrate if proton decay can occur.<ref name="dying"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 3×1043 (30 tredecillion) | The estimated time for all nucleons in the observable universe to decay, if the hypothesized proton half-life takes the largest possible value of 1041 years,<ref name="dying"/> assuming that the Big Bang was inflationary and that the same process that made baryons predominate over anti-baryons in the early universe makes protons decay. By this time, if protons do decay, the Black Hole Era, in which black holes are the only remaining celestial objects, begins.<ref name="dying"/><ref name="five ages"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 3.14×1050 (314 quindecillion) | The estimated time until a micro black hole of one Earth mass today will have decayed into subatomic particles by the emission of Hawking radiation.<ref name="Page 1976"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 1065 (100 vigintillion) | Assuming that protons do not decay, the estimated time for rigid objects, from free-floating rocks in space to planets, to rearrange their atoms and molecules via quantum tunnelling. On this timescale, any discrete body of matter "behaves like a liquid" and becomes a smooth sphere due to diffusion and gravity.<ref name="dyson"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 1.16×1067 (11.6 unvigintillion) | The estimated time until a black hole of one solar mass today will have decayed by the emission of Hawking radiation.<ref name="Page 1976"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 1.54×1091–1.41×1092 (15.4–141 novemvigintillion) | The estimated time until the resulting supermassive black hole of "Milkomeda"/"Milkdromeda" from the merger of Sagittarius A* and the P2 concentration during the collision of the Milky Way and Andromeda galaxies<ref>{{Cite news |last=Overbye |first=Denis |author-link=Dennis Overbye |date=16 September 2015 |title=More Evidence for Coming Black Hole Collision |url=https://www.nytimes.com/2015/09/22/science/space/more-evidence-for-coming-black-hole-collision.html |work=The New York Times}}</ref> will have vanished by the emission of Hawking radiation,<ref name="Page 1976"/> assuming it does not accrete any additional matter nor merge with other black holes—though it is most likely that this supermassive black hole will nonetheless merge with other supermassive black holes during the gravitational collapse towards "Milkomeda"/"Milkdromeda" of other Local Group galaxies.<ref>{{Cite web |last=L. |first=Logan Richard |date=2021 |title=Black holes can help us answer many long-asked questions. |url=https://www.microscopy-uk.net/black-holes-can-help-us-answer-many-long-asked-questions/ |archive-url=https://web.archive.org/web/20210515162122/https://www.microscopy-uk.net/black-holes-can-help-us-answer-many-long-asked-questions/ |archive-date=15 May 2021 |access-date=30 May 2023 |website=Microscopy UK – Science & Education |publisher=Micscape |quote="When galaxies collide, the supermassive black holes in the central contract eventually find their way into the centre of the newly created galaxy where they are ultimately pulled together."}}</ref> This supermassive black hole might be the very last entity from the former Local Group to disappear—and the last evidence of its existence. |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 10106 – 2.1×10109 | The estimated time until ultramassive black holes of 1014 (100 trillion) solar masses, predicted to form during the gravitational collapse of galaxy superclusters,<ref>{{Cite journal |last=Frautschi |first=S. |year=1982 |title=Entropy in an expanding universe |journal=Science |volume=217 |issue=4560 |pages=593–599 |bibcode=1982Sci...217..593F |doi=10.1126/science.217.4560.593 |pmid=17817517 |s2cid=27717447 |quote=p. 596: table 1 and section "black hole decay" and previous sentence on that page: "Since we have assumed a maximum scale of gravitational binding – for instance, superclusters of galaxies – black hole formation eventually comes to an end in our model, with masses of up to 1014{{solar mass}} ... the timescale for black holes to radiate away all their energy ranges ... to 10106 years for black holes of up to 1014{{solar mass}}}}"</ref> decay by Hawking radiation.<ref name="Page 1976"/> This marks the end of the Black Hole Era. Beyond this time, if protons do decay, the universe enters the Dark Era, in which all physical objects have decayed to subatomic particles, gradually winding down to their final energy state in the heat death of the universe.<ref name="dying"/><ref name="five ages"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 10161 | A 2018 estimate of Standard Model lifetime before collapse of a false vacuum; 95% confidence interval is 1065 to 101383 years due in part to uncertainty about the top quark's mass.<ref>{{Cite journal |last1=Andreassen |first1=Anders |last2=Frost |first2=William |last3=Schwartz |first3=Matthew D. |date=12 March 2018 |title=Scale-invariant instantons and the complete lifetime of the standard model |journal=Physical Review D |volume=97 |issue=5 |article-number=056006 |arxiv=1707.08124 |bibcode=2018PhRvD..97e6006A |doi=10.1103/PhysRevD.97.056006 |s2cid=118843387}}</ref><ref group="note">Manuscript was updated after publication; lifetime numbers are taken from the latest revision at https://arxiv.org/abs/1707.08124.</ref> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 10200 | The highest estimate for the time it would take for all nucleons in the observable universe to decay, provided they do not decay via the above process but instead through any one of many different mechanisms allowed in modern particle physics (higher-order baryon non-conservation processes, virtual black holes, sphalerons, etc.) on timescales of 1046 to 10200 years.<ref name="five ages"/> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 101100–32000 | The estimated time for black dwarfs of 1.2 solar masses or more to undergo supernovae as a result of slow silicon–nickel–iron fusion, as the declining electron fraction lowers their Chandrasekhar limit, assuming protons do not decay.<ref>{{Cite journal |last=Caplan |first=M. E. |date=7 August 2020 |title=Black Dwarf Supernova in the Far Future |journal=MNRAS |volume=497 |pages=4357–4362 |arxiv=2008.02296 |bibcode=2020MNRAS.497.4357C |doi=10.1093/mnras/staa2262 |s2cid=221005728 |doi-access=free |number=1–6}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt= Astronomy and astrophysics|Astronomy and astrophysics | 101500 | Assuming that protons do not decay, the estimated time until all baryonic matter in stellar remnants, planets and planetary-mass objects will have either fused together via muon-catalyzed fusion to form iron-56 or decayed from a higher mass element into iron-56 to form iron stars.<ref name="dyson"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | <math>10^{10^{26}}</math><ref name="bignumber" group="note"><math>10^{10^{26}}</math> is 1 followed by 1026 (100 septillion) zeroes.</ref><ref name="bignumber2" group="note">Although listed in years for convenience, the numbers at this point are so vast that their digits would remain unchanged regardless of which conventional units they were listed in, be they nanoseconds or star lifespans.</ref> | A low estimate for the time until all iron stars collapse via quantum tunnelling into black holes, assuming no proton decay or virtual black holes, and that Planck-scale black holes can exist.<ref name="dyson"/>

On this vast timescale, even ultra-stable iron stars will have been destroyed by quantum-tunnelling events. At this lower end of the timescale, iron stars decay directly to black holes, as this decay mode is much more favourable than decaying into a neutron star (which has an expected timescale of <math>10^{10^{76}}</math> years)<ref name="dyson"/> and later decaying into a black hole. On these timescales, the subsequent evaporation of each resulting black hole into subatomic particles (a process lasting roughly 10100 years) and the subsequent shift to the Dark Era is instantaneous. |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | <math>10^{10^{50}}</math><ref name="prob" group="note"/><ref name="bignumber2" group="note"/><ref group="note"><math>10^{10^{50}}</math> is 1 followed by 1050 (100 quindecillion) zeroes.</ref> | The estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease.<ref name="linde"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | <math>10^{10^{76}}</math><ref name="bignumber2" group="note"/> | Highest estimate for the time until all iron stars collapse via quantum tunnelling into neutron stars or black holes, assuming no proton decay or virtual black holes, and that black holes below the Chandrasekhar mass cannot form directly.<ref name="dyson"/> On these timescales, neutron stars above the Chandrasekhar mass rapidly collapse into black holes, and black holes formed by these processes instantly evaporate into subatomic particles.

This is also the highest estimated possible time for the Black Hole Era (and subsequent Dark Era) to commence. Beyond this point, it is almost certain that the universe will be an almost pure vacuum, gradually winding down its energy level until it reaches its final energy state, assuming it does not happen before this time. |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | <math>10^{10^{120}}</math><ref name="bignumber2" group="note"/> | The highest estimate for the time it takes for the universe to reach its final energy state.<ref name="linde"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | <math>10^{10^{10^{56}}}</math><ref name="prob" group="note"/><ref name="bignumber2" group="note"/> | Around this vast timeframe, quantum tunnelling in any isolated patch of the universe could generate new inflationary events, resulting in new Big Bangs giving birth to new universes.<ref name="carroll and chen"/>

''(Because the total number of ways in which all the subatomic particles in the observable universe can be combined is <math>10^{10^{115}}</math>,<ref name="TegmarkPUstaple">{{Cite journal |last=Tegmark |first=Max |author-link=Max Tegmark |date=7 February 2003 |title=Parallel universes. Not just a staple of science fiction, other universes are a direct implication of cosmological observations |journal=Scientific American |volume=288 |issue=5 |pages=40–51 |arxiv=astro-ph/0302131 |bibcode=2003SciAm.288e..40T |doi=10.1038/scientificamerican0503-40 |pmid=12701329}}</ref><ref>{{Cite journal |last=Tegmark |first=Max |author-link=Max Tegmark |date=7 February 2003 |editor-last=Barrow |editor-first=J. D. |editor2-last=Davies |editor2-first=P. C. W. |editor3-last=Harper |editor3-first=C. L. |title=Parallel Universes |journal=In "Science and Ultimate Reality: From Quantum to Cosmos", Honoring John Wheeler's 90th Birthday |volume=288 |issue=5 |pages=40–51 |arxiv=astro-ph/0302131 |bibcode=2003SciAm.288e..40T |doi=10.1038/scientificamerican0503-40 |pmid=12701329}}</ref> a number which, when multiplied by <math>10^{10^{10^{56}}}</math>, has a difference so small from <math>10^{10^{10^{56}}}</math> that it is functionally zero, this is also the time required for a quantum-tunnelled and quantum fluctuation-generated Big Bang to produce a new universe identical to our own, assuming that every new universe contained at least the same number of subatomic particles and obeyed laws of physics within the landscape predicted by string theory.)''<ref>{{Cite journal |last=Douglas |first=M. |author-link=Michael R. Douglas |date=21 March 2003 |title=The statistics of string / M theory vacua |journal=JHEP |volume=0305 |issue=46 |page=046 |arxiv=hep-th/0303194 |bibcode=2003JHEP...05..046D |doi=10.1088/1126-6708/2003/05/046 |s2cid=650509}}</ref><ref>{{Cite journal |last1=Ashok |first1=S. |last2=Douglas |first2=M. |author-link2=Michael R. Douglas |year=2004 |title=Counting flux vacua |journal=JHEP |volume=0401 |issue=60 |page=060 |arxiv=hep-th/0307049 |bibcode=2004JHEP...01..060A |doi=10.1088/1126-6708/2004/01/060 |s2cid=1969475}}</ref> |}

== Humanity and human constructs == '''Keys''' {| class="wikitable" |- | style="background: lavender;" | 16px|alt=Astronomy and astrophysics|Astronomy and astrophysics | Astronomy and astrophysics |- | style="background: #f0dc82;" | 16px|alt=Geology and planetary science|Geology and planetary science | Geology and planetary science |- | style="background: #CEFF00;" | 16px|alt=Biology|Biology | Biology |- | style="background: #FFE4E1;" | 16px|alt=Particle physics|Particle physics | Particle physics |- | style="background: #e0ffff;" | 16px|alt=Mathematics|Mathematics | Mathematics |- | 16px|class=skin-invert-image|alt=Technology and culture|Technology and culture | Technology and culture |}

To date, five spacecraft (''Voyager 1'', ''Voyager 2'', ''Pioneer 10'', ''Pioneer 11'' and ''New Horizons'') are on trajectories that will take them out of the Solar System and into interstellar space. Barring an extremely unlikely collision with some object, all five should persist indefinitely.<ref name="time"/>

{| class="wikitable" style="width: 100%; margin-right: 0;" |- ! scope="col" | 16px|class=skin-invert-image|link=#Keys ! scope="col" | Date (CE) or {{nowrap|years from now}} ! scope="col" | Event |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|Technology and culture | 3183 CE | The ''Zeitpyramide'' (''time pyramid''), a public art work started in 1993 at Wemding, Germany, is scheduled for completion.<ref name="Conception">[http://www.zeitpyramide.de/ Conception] {{Webarchive|url=https://web.archive.org/web/20110719115509/http://www.zeitpyramide.de/ |date=19 July 2011 }} Official ''Zeitpyramide'' website. Retrieved 14 December 2010.</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|Technology and culture | 4017 CE | Maximum lifespan of the data films in Arctic World Archive, a repository that contains code of open-source projects on GitHub along with other data of historical interest (if stored in optimal conditions).<ref>{{Cite web |last=Linder |first=Courtney |date=15 November 2019 |title=Microsoft is Storing Source Code in an Arctic Cave |url=https://www.popularmechanics.com/technology/security/a29811351/microsoft-secret-code-vault/ |url-status=live |archive-url=https://web.archive.org/web/20210316200734/https://www.popularmechanics.com/technology/security/a29811351/microsoft-secret-code-vault/ |archive-date=16 March 2021 |access-date=25 July 2021 |website=Popular Mechanics}}</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|Technology and culture | 5207 CE | According to Michio Kaku, the time by which humanity will be a Type II civilization, capable of harnessing all the energy of its host star.<ref name="Kaku-2007">{{Cite web |last=Kaku |first=Michio |author-link=Michio Kaku |date=2007 |title=The Physics of Extraterrestrial Civilizations: Official Website of Dr Michio Kaku |url=https://mkaku.org/home/articles/the-physics-of-extraterrestrial-civilizations |access-date=17 May 2025}}</ref> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 10,000 | The Waste Isolation Pilot Plant for nuclear weapons waste is planned to be protected until this time, with a "Permanent Marker" system designed to warn off visitors through multiple languages (the six UN languages and Navajo) and pictograms.<ref>{{Cite web |date=30 August 2004 |title=Permanent Markers Implementation Plan |url=http://www.wipp.energy.gov/picsprog/test1/Permanent_Markers_Implementation_Plan_rev1.pdf |archive-url=https://web.archive.org/web/20060928144722/http://www.wipp.energy.gov/PICsProg/Test1/Permanent_Markers_Implementation_Plan_rev1.pdf |archive-date=28 September 2006 |publisher=United States Department of Energy}}</ref> The Human Interference Task Force has provided the theoretical basis for United States plans for future nuclear semiotics.<ref>{{Cite web |last=Chapman |first=Kit |date=5 May 2022 |title=How do we warn future generations about our toxic waste? |url=https://newhumanist.org.uk/5958/how-do-we-warn-future-generations-about-our-toxic-waste |access-date=14 August 2022 |website=newhumanist.org.uk |language=en-GB}}</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|Technology and culture | 10,000 | Planned lifespan of the Long Now Foundation's several ongoing projects, including a 10,000-year clock known as the Clock of the Long Now, the Rosetta Project and the Long Bet Project.<ref name="longnow"/>

Estimated lifespan of the HD-Rosetta analog disc—an ion beam-etched writing medium on nickel plate, a technology developed at Los Alamos National Laboratory and later commercialized. (The Rosetta Project uses this technology, named after the Rosetta Stone.) |- | style="background: #CEFF00;" | 16px|link=#Keys|alt=Biology|Biology | 10,000 | Projected lifespan of Norway's Svalbard Global Seed Vault.<ref>{{Cite news |date=20 March 2008 |title=A Visit to the Doomsday Vault |url=https://www.cbsnews.com/news/a-visit-to-the-doomsday-vault/ |url-status=live |archive-url=https://web.archive.org/web/20210308220206/https://www.cbsnews.com/news/a-visit-to-the-doomsday-vault/ |archive-date=8 March 2021 |access-date=5 January 2018 |work=CBS News}}</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|Technology and culture | 10,000 | Most probable estimated lifespan of technological civilization, according to Frank Drake's original formulation of the Drake equation.<ref>{{Cite book |last1=Smith |first1=Cameron |title=Emigrating Beyond Earth: Human Adaptation and Space Colonization |last2=Davies |first2=Evan T. |date=2012 |publisher=Springer |isbn=978-1-4614-1165-9 |page=258}}</ref> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt=Biology|Biology | 10,000 | If globalization trends lead to panmixia, human genetic variation will no longer be regionalized, as the effective population size will equal the actual population size.<ref>{{Cite book |last1=Klein |first1=Jan |title=Where Do We Come From?: The Molecular Evidence for Human Descent |last2=Takahata |first2=Naoyuki |date=2002 |publisher=Springer |isbn=978-3-662-04847-4 |page=395}}</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|technology and culture | 20,000 | The Chernobyl exclusion zone is expected to become habitable again.<ref>{{Cite news |last=Blakemore |first=Erin |date=17 May 2019 |title=Chernobyl disaster facts and information |url=https://www.nationalgeographic.com/culture/article/chernobyl-disaster |access-date=5 November 2024 |work=Culture |publisher=National Geographic |language=en}}</ref> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 24,110 | Half-life of plutonium-239.{{NUBASE2016|ref}} At this point the Chernobyl Exclusion Zone, the {{convert|2600|km2|adj=mid}} area of Ukraine and Belarus left deserted by the 1986 Chernobyl disaster, will return to normal levels of radiation.<ref name="TimeDisaster">{{Cite book |title=Time: Disasters that Shook the World |publisher=Time Home Entertainment |year=2012 |isbn=978-1-60320-247-3 |location=New York City}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 25,000 | The Arecibo message, a collection of radio data transmitted on 16 November 1974, will reach the distance of its destination: the globular cluster Messier 13.<ref name="glob"/> This is the only interstellar radio message sent to such a distant region of the galaxy. There will be a 24-light-year shift in the cluster's position in the galaxy during the time taken for the message to reach it, but as the cluster is 168 light-years in diameter, the message will still reach its destination.<ref>{{Cite web |last=Deamer |first=Dave |title=In regard to the email from |date=27 August 2014 |url=http://www.science20.com/comments/28100/In_regard_to_the_email_from |archive-url=https://web.archive.org/web/20150924095532/http://www.science20.com/comments/28100/In_regard_to_the_email_from |archive-date=24 September 2015 |access-date=14 November 2014 |publisher=Science 2.0}}</ref> Any reply will take at least another 25,000 years from the time of its transmission. |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|technology and culture | 14 September 30828 CE | Maximum system time for 64-bit NTFS-based Windows operating system.<ref>{{Cite news |date=6 April 2013 |title=Interpretation of NTFS Timestamps |url=https://www.forensicfocus.com/articles/interpretation-of-ntfs-timestamps/ |url-status=live |archive-url=https://web.archive.org/web/20210308204004/https://www.forensicfocus.com/articles/interpretation-of-ntfs-timestamps/ |archive-date=8 March 2021 |access-date=31 July 2021 |work=Forensic Focus}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 33,800 | ''Pioneer 10'' passes within 3.4 light-years of Ross 248.<ref name="lavender">{{Cite journal |last1=Bailer-Jones |first1=Coryn A. L. |last2=Farnocchia |first2=Davide |date=3 April 2019 |title=Future stellar flybys of the Voyager and Pioneer spacecraft |journal=Research Notes of the American Astronomical Society |volume=3 |page=59 |arxiv=1912.03503 |bibcode=2019RNAAS...3...59B |doi=10.3847/2515-5172/ab158e |s2cid=134524048 |doi-access=free |number=59}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 42,200 | ''Voyager 2'' passes within 1.7 light-years of Ross 248.<ref name="lavender"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 44,100 | ''Voyager 1'' passes within 1.8 light-years of Gliese 445.<ref name="lavender"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 46,600 | ''Pioneer 11'' passes within 1.9 light-years of Gliese 445.<ref name="lavender"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 50,000 | Estimated atmospheric lifetime of tetrafluoromethane, the most durable greenhouse gas.<ref>{{Cite web |last1=Artaxo |first1=Paulo |last2=Berntsen |first2=Terje |last3=Betts |first3=Richard |last4=Fahey |first4=David W. |last5=Haywood |first5=James |last6=Lean |first6=Judith |author-link6=Judith Lean |last7=Lowe |first7=David C. |last8=Myhre |first8=Gunnar |last9=Nganga |first9=John |last10=Prinn |first10=Ronald |last11=Raga |first11=Graciela |last12=Schulz |first12=Michael |last13=van Dorland |first13=Robert |date=February 2018 |title=Changes in Atmospheric Constituents and in Radiative Forcing |url=https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter2-1.pdf |url-status=live |archive-url=https://web.archive.org/web/20190218141843/https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter2-1.pdf |archive-date=18 February 2019 |access-date=17 March 2021 |publisher=Intergovernmental Panel on Climate Change |page=212}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 90,300 | ''Pioneer 10'' passes within 0.76 light-years of HIP 117795.<ref name="lavender"/> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 100,000+ | Time required to terraform Mars with an oxygen-rich breathable atmosphere, using only plants with solar efficiency comparable to the biosphere currently found on Earth.<ref>{{Cite journal |last1=McKay |first1=Christopher P. |last2=Toon |first2=Owen B. |last3=Kasting |first3=James F. |date=8 August 1991 |title=Making Mars habitable |url=https://zenodo.org/record/1233115 |url-status=live |journal=Nature |volume=352 |issue=6335 |pages=489–496 |bibcode=1991Natur.352..489M |doi=10.1038/352489a0 |pmid=11538095 |s2cid=2815367 |archive-url=https://web.archive.org/web/20210308162717/https://zenodo.org/record/1233115 |archive-date=8 March 2021 |access-date=23 June 2019}}</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=Technology and culture|Technology and culture | 100,000–1 million | Estimated time by which humanity will be a Type III civilization, and could colonize the Milky Way galaxy and become capable of harnessing all the energy of the galaxy, assuming a velocity of 10% the speed of light.<ref name="typeiii"/> |- | style="background: #FFE4E1;" | 16px|link=#Keys|alt=Particle physics|Particle physics | 250,000 | The estimated minimum time at which the spent plutonium stored at New Mexico's Waste Isolation Pilot Plant will cease to be radiologically lethal to humans.<ref>{{Cite web |last=Biello |first=David |date=28 January 2009 |title=Spent Nuclear Fuel: A Trash Heap Deadly for 250,000 Years or a Renewable Energy Source? |url=https://www.scientificamerican.com/article/nuclear-waste-lethal-trash-or-renewable-energy-source/ |url-status=live |archive-url=https://web.archive.org/web/20210710002930/https://www.scientificamerican.com/article/nuclear-waste-lethal-trash-or-renewable-energy-source/ |archive-date=10 July 2021 |access-date=5 January 2018 |website=Scientific American}}</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|technology and culture | 13 September 275760 CE | Maximum system time for the JavaScript programming language.<ref>{{Cite web |title=Date - JavaScript |url=https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date |url-status=live |archive-url=https://web.archive.org/web/20210721082721/https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date |archive-date=21 July 2021 |access-date=27 July 2021 |website=developer.mozilla.org |publisher=Mozilla}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 492,300 | ''Voyager 1'' passes within 1.3 light-years of HD 28343.<ref name="lavender"/> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|technology and culture | 1 million | Estimated lifespan of Memory of Mankind (MOM) self storage-style repository in Hallstatt salt mine in Austria, which stores information on inscribed tablets of stoneware.<ref>{{Cite web |title=Memory of Mankind |url=https://www.memory-of-mankind.com/ |url-status=live |archive-url=https://web.archive.org/web/20210716092821/https://www.memory-of-mankind.com/ |archive-date=16 July 2021 |access-date=4 March 2019 |website=memory-of-mankind.com}}</ref>

Planned lifespan of the Human Document Project being developed at the University of Twente in the Netherlands.<ref>{{Cite web |title=Human Document Project 2014 |url=http://hudoc2014.manucodiata.org/ |url-status=live |archive-url=https://web.archive.org/web/20140519094549/http://hudoc2014.manucodiata.org/ |archive-date=19 May 2014 |access-date=19 May 2014 |website=manucodiata.org}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 1 million | Current glass objects in the environment will be decomposed.<ref>{{Cite web |title=Time it takes for garbage to decompose in the environment |url=http://des.nh.gov/organization/divisions/water/wmb/coastal/trash/documents/marine_debris.pdf |archive-url=https://web.archive.org/web/20140609083232/http://des.nh.gov/organization/divisions/water/wmb/coastal/trash/documents/marine_debris.pdf |archive-date=9 June 2014 |access-date=23 May 2014 |publisher=New Hampshire Department of Environmental Services}}</ref>

Various public monuments composed of hard granite will have eroded by one metre, in a moderate climate and assuming a rate of 1 Bubnoff unit (1 mm in 1,000 years, or ≈1 inch in 25,000 years).<ref>{{Cite book |last=Lyle |first=Paul |title=Between Rocks And Hard Places: Discovering Ireland's Northern Landscapes |date=2010 |publisher=Geological Survey of Northern Ireland |isbn=978-0-337-09587-0}}</ref>

Without maintenance, the Great Pyramid of Giza will have eroded to the point where it is unrecognizable.<ref>{{Cite book |last=Weisman |first=Alan |author-link=Alan Weisman |url=https://archive.org/details/worldwithoutus00weis |title=The World Without Us |date=10 July 2007 |publisher=Thomas Dunne Books/St. Martin's Press |isbn=978-0-312-34729-1 |location=New York |pages=[https://archive.org/details/worldwithoutus00weis/page/171 171]–172 |oclc=122261590 |url-access=limited}}</ref>

On the Moon, Neil Armstrong's "one small step" footprint at Tranquility Base will erode by this time, along with those left by all twelve Apollo moonwalkers, due to the accumulated effects of space weathering.<ref name="meadows 2007"/><ref>{{Cite web |title=Apollo 11 – First Footprint on the Moon |url=http://www.nasa.gov/audience/forstudents/k-4/home/F_Apollo_11.html |url-status=live |archive-url=https://web.archive.org/web/20210403084654/https://www.nasa.gov/audience/forstudents/k-4/home/F_Apollo_11.html |archive-date=3 April 2021 |access-date=26 May 2014 |website=Student Features |publisher=NASA}}</ref> (Normal erosion processes active on Earth are not present on the Moon because of its almost complete lack of atmosphere.) |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1.2 million | ''Pioneer 11'' comes within three light-years of Delta Scuti.<ref name="lavender"/> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 2 million | ''Pioneer 10'' passes near the bright star Aldebaran.<ref name="Pioneer Ames"/> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt=Biology|Biology | 2 million | Vertebrate species separated for this long will generally undergo allopatric speciation.<ref>{{Cite journal |last1=Avise |first1=John |author-link1=John Avise |last2=D. Walker |last3=G. C. Johns |date=22 September 1998 |title=Speciation durations and Pleistocene effects on vertebrate phylogeography |journal=Philosophical Transactions of the Royal Society B |volume=265 |issue=1407 |pages=1707–1712 |doi=10.1098/rspb.1998.0492 |pmc=1689361 |pmid=9787467}}</ref> Evolutionary biologist James W. Valentine predicted that if humanity has been dispersed among genetically isolated space colonies over this time, the galaxy will host an evolutionary radiation of multiple human species with a "diversity of form and adaptation that would astound us".<ref>{{Cite book |last=Valentine |first=James W. |author-link=James W. Valentine |title=Interstellar Migration and the Human Experience |date=1985 |publisher=University of California Press |isbn=978-0-520-05878-1 |editor-last=Finney |editor-first=Ben R. |editor-link=Ben Finney |page=274 |chapter=The Origins of Evolutionary Novelty And Galactic Colonization |editor-last2=Jones |editor-first2=Eric M.}}</ref> This would be a natural process of isolated populations, unrelated to potential deliberate genetic enhancement technologies. |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 4 million | ''Pioneer 11'' passes near one of the stars in the constellation Aquila.<ref name="Pioneer Ames"/> |- | style="background: #CEFF00;" | 16px|link=#Keys|alt= Biology|Biology | 5–10 million | Due to gradual degeneration, the Y chromosome will have disappeared.<ref>{{Cite journal |last1=Wilson |first1=Jason |last2=Staley |first2=Joshua M. |last3=Wyckoff |first3=Gerald J. |date=7 February 2020 |title=Extinction of chromosomes due to specialization is a universal occurrence |journal=Scientific Reports |language=en |volume=10 |issue=1 |page=2170 |bibcode=2020NatSR..10.2170W |doi=10.1038/s41598-020-58997-2 |issn=2045-2322 |pmc=7005762 |pmid=32034231}}</ref><ref>{{Cite journal |vauthors=Graves JA |year=2004 |title=The degenerate Y chromosome--can conversion save it? |journal=Reproduction, Fertility, and Development |volume=16 |issue=5 |pages=527–534 |doi=10.1071/RD03096 |pmid=15367368}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 7.2 million | Without maintenance, Mount Rushmore will have eroded to the point where it is unrecognizable.<ref>{{Cite book |last=Weisman |first=Alan |author-link=Alan Weisman |url=https://archive.org/details/worldwithoutus00weis |title=The World Without Us |date=10 July 2007 |publisher=Thomas Dunne Books/St. Martin's Press |isbn=978-0-312-34729-1 |location=New York |page=[https://archive.org/details/worldwithoutus00weis/page/182 182] |oclc=122261590 |url-access=limited}}</ref> |- | style="background: #e0ffff;" | 16px|link=#Keys|alt=Mathematics|Mathematics | 8 million<ref name="prob" group="note"/> | Humanity has a 95% probability of extinction by this date, according to J. Richard Gott's formulation of the controversial Doomsday argument.<ref>{{Cite journal |last=Gott |first=J. Richard |date=May 1993 |title=Implications of the Copernican principle for our future prospects |journal=Nature |language=en |volume=363 |issue=6427 |pages=315–319 |bibcode=1993Natur.363..315G |doi=10.1038/363315a0 |issn=0028-0836 |s2cid=4252750}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 8 million | Most probable lifespan of the Pioneer 10 plaques before the etching is destroyed by poorly understood interstellar erosion processes.<ref>{{Cite web |last=Lasher |first=Lawrence |title=Pioneer Mission Status |url=http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNStat.html |archive-url=https://web.archive.org/web/20000408152959/http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNStat.html |archive-date=8 April 2000 |publisher=NASA |quote=[Pioneer's speed is] about 12 km/s... [the plate etching] should survive recognizable at least to a distance ≈10 parsecs, and most probably to 100 parsecs.}}</ref>

The ''LAGEOS'' satellites' orbits will decay, and they will re-enter Earth's atmosphere, carrying with them a message to any far future descendants of humanity and a map of the continents as they are expected to appear then.<ref name="lageos"/> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|Technology and culture | 100 million | Maximal estimated lifespan of technological civilization, according to Frank Drake's original formulation of the Drake equation.<ref>{{Cite book |last1=Bignami |first1=Giovanni F. |url=https://archive.org/details/scenarioforinter00bign |title=A Scenario for Interstellar Exploration and Its Financing |last2=Sommariva |first2=Andrea |date=2013 |publisher=Springer |isbn=978-88-470-5337-3 |page=[https://archive.org/details/scenarioforinter00bign/page/n29 23] |bibcode=2013sief.book.....B |url-access=limited}}</ref> |- | style="background: #f0dc82;" | 16px|link=#Keys|alt=Geology and planetary science|Geology and planetary science | 100 million | Future archaeologists should be able to identify an "Urban Stratum" of fossilized great coastal cities, mostly through the remains of underground infrastructure such as building foundations and utility tunnels.<ref>{{Cite book |last=Zalasiewicz |first=Jan |title=The Earth After Us: What legacy will humans leave in the rocks? |date=25 September 2008 |publisher=Oxford University Press}}, [https://web.archive.org/web/20140513011343/http://www.stanford.edu/dept/archaeology/cgi-bin/archaeolog/?p=239 Review in Stanford Archaeology]</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|Technology and culture | 1 billion | Estimated lifespan of "Nanoshuttle memory device" using an iron nanoparticle moved as a molecular switch through a carbon nanotube, a technology developed at the University of California at Berkeley.<ref>{{Cite journal |last1=Begtrup |first1=G. E. |last2=Gannett |first2=W. |last3=Yuzvinsky |first3=T. D. |last4=Crespi |first4=V. H. |last5=Zettl |first5=A. |date=13 May 2009 |title=Nanoscale Reversible Mass Transport for Archival Memory |url=http://www.physics.berkeley.edu/research/zettl/pdf/363.NanoLet.9-Begtrup.pdf |journal=Nano Letters |volume=9 |issue=5 |pages=1835–1838 |bibcode=2009NanoL...9.1835B |citeseerx=10.1.1.534.8855 |doi=10.1021/nl803800c |pmid=19400579 |archive-url=https://web.archive.org/web/20100622232231/http://www.physics.berkeley.edu/research/zettl/pdf/363.NanoLet.9-Begtrup.pdf |archive-date=22 June 2010}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1 billion | Estimated lifespan of the two Voyager Golden Records before the information stored on them is rendered unrecoverable.<ref>{{Cite AV media |url=https://www.npr.org/2010/02/12/123534818/carl-sagan-and-ann-druyans-ultimate-mix-tape |title=Carl Sagan And Ann Druyan's Ultimate Mix Tape |date=12 February 2010 |last1=Abumrad |first1=Jad |author-link1=Jad Abumrad |last2=Krulwich |first2=Robert |author-link2=Robert Krulwich |type=Radio |publisher=NPR |work=Radiolab}}</ref>

Estimated time for an astroengineering project to alter the Earth's orbit, compensating for the Sun's increasing brightness and outward migration of the habitable zone, accomplished by repeated asteroid gravity assists.<ref>{{Cite journal |last1=Korycansky |first1=D. G. |last2=Laughlin |first2=Gregory |author-link2=Gregory P. Laughlin |last3=Adams |first3=Fred C. |author-link3=Fred Adams |year=2001 |title=Astronomical engineering: a strategy for modifying planetary orbits |journal=Astrophysics and Space Science |volume=275 |issue=4 |pages=349–366 |arxiv=astro-ph/0102126 |bibcode=2001Ap&SS.275..349K |doi=10.1023/A:1002790227314 |s2cid=5550304 |id=Astrophys.Space Sci.275:349-366, 2001 |hdl=2027.42/41972}}</ref><ref>{{Cite journal |last=Korycansky |first=D. G. |year=2004 |title=Astroengineering, or how to save the Earth in only one billion years |url=http://www.astroscu.unam.mx/rmaa/RMxAC..22/PDF/RMxAC..22_korycansky.pdf |url-status=live |journal=Revista Mexicana de Astronomía y Astrofísica |volume=22 |pages=117–120 |bibcode=2004RMxAC..22..117K |archive-url=https://web.archive.org/web/20150923175649/http://www.astroscu.unam.mx/rmaa/RMxAC..22/PDF/RMxAC..22_korycansky.pdf |archive-date=23 September 2015 |access-date=7 September 2014}}</ref> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|technology and culture | 292277026596 CE (292 billion) | Numeric overflow in system time for 64-bit Unix systems.<ref>{{Cite web |date=19 May 2019 |title=Date/Time Conversion Contract Language |url=https://its.ny.gov/sites/default/files/documents/nys-p98-003_date_time_conversion_contract_language_1.pdf |url-status=live |archive-url=https://web.archive.org/web/20210430113627/https://its.ny.gov/sites/default/files/documents/nys-p98-003_date_time_conversion_contract_language_1.pdf |archive-date=30 April 2021 |access-date=16 October 2020 |publisher=Office of Information Technology Services |location=New York}}</ref> |- | style="background: lavender;" | 16px|link=#Keys|alt=Astronomy and astrophysics|Astronomy and astrophysics | 1020 (100 quintillion)<ref name="prob" group="note"/> | Estimated timescale for the Pioneer and Voyager spacecraft to collide with a star (or stellar remnant).<ref name="lavender"/> |- | 16px|class=skin-invert-image|link=#Keys|alt=technology and culture|technology and culture | {{val|3e19}} – {{val|3e21}} (30 quintillion to 3 sextillion) | Estimated lifespan of "Superman memory crystal" data storage using femtosecond laser-etched nanostructures in glass, a technology developed at the University of Southampton, at an ambient temperature of {{cvt|30|C|F K}}.<ref>{{Cite journal |last1=Zhang |first1=J. |last2=Gecevičius |first2=M. |last3=Beresna |first3=M. |last4=Kazansky |first4=P. G. |year=2014 |title=Seemingly unlimited lifetime data storage in nanostructured glass |url=https://www.researchgate.net/publication/260004721 |url-status=live |journal=Phys. Rev. Lett. |volume=112 |issue=3 |article-number=033901 |bibcode=2014PhRvL.112c3901Z |doi=10.1103/PhysRevLett.112.033901 |pmid=24484138 |s2cid=27040597 |archive-url=https://web.archive.org/web/20210802032743/https://www.researchgate.net/publication/260004721_Seemingly_Unlimited_Lifetime_Data_Storage_in_Nanostructured_Glass |archive-date=2 August 2021 |access-date=6 September 2018}}</ref><ref>{{Cite journal |last1=Zhang |first1=J. |last2=Gecevičius |first2=M. |last3=Beresna |first3=M. |last4=Kazansky |first4=P. G. |date=June 2013 |title=5D Data Storage by Ultrafast Laser Nanostructuring in Glass |url=http://www.orc.soton.ac.uk/fileadmin/downloads/5D_Data_Storage_by_Ultrafast_Laser_Nanostructuring_in_Glass.pdf |journal=CLEO: Science and Innovations |pages=CTh5D–9 |archive-url=https://web.archive.org/web/20140906152109/http://www.orc.soton.ac.uk/fileadmin/downloads/5D_Data_Storage_by_Ultrafast_Laser_Nanostructuring_in_Glass.pdf |archive-date=6 September 2014}}</ref> |}

== Notes == {{reflist|30em|group=note}}

== References == {{cols|colwidth=26em}} <references>

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<ref name="carroll and chen">{{Cite arXiv |eprint=hep-th/0410270 |first1=Sean M. |last1=Carroll |author-link1=Sean M. Carroll |first2=Jennifer |last2=Chen |title=Spontaneous Inflation and the Origin of the Arrow of Time |date=27 October 2004 }}</ref>

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=== Bibliography === * {{Cite book |last=Adams |first=Fred C. |author-link=Fred Adams |chapter-url=https://books.google.com/books?id=-Jxc88RuJhgC&pg=PA33 |title=Global catastrophic risks |date=2008 |publisher=Oxford University Press |isbn=978-0-19-857050-9 |editor-last=Bostrom |editor-first=Nick |chapter=Long term astrophysical processes |editor-last2=Ćirković |editor-first2=Milan M. |editor-link2=Milan M. Ćirković}} * {{Cite book |last=Brownlee |first=Donald E. |author-link=Donald E. Brownlee |title=Heliophysics: Evolving Solar Activity and the Climates of Space and Earth |date=2010 |publisher=Cambridge University Press |isbn=978-0-521-11294-9 |editor-last=Schrijver |editor-first=Carolus J. |chapter=Planetary habitability on astronomical time scales |editor-last2=Siscoe |editor-first2=George L. |chapter-url=https://books.google.com/books?id=M8NwTYEl0ngC}}