{{Short description|Near-Earth asteroid}} {{Use dmy dates |date=June 2016}} {{Infobox planet | minorplanet = yes | name = 469219 Kamo{{okina}}oalewa | background = #FFC2E0 | image = Kamo'oalewa CFHT 2016-04-28 annotated.gif | caption = Kamoʻoalewa imaged by the [[Canada–France–Hawaii Telescope]] on 28 April 2016 | discovery_ref = <ref name="MPC-object" /> | discoverer = [[Pan-STARRS]] | discovery_site = [[Haleakala Observatory]] | discovered = 27 April 2016 | mpc_name = (469219) {{mp|2016 HO|3}} | alt_names = {{mp|2016 HO|3}} | pronounced = {{IPAc-en|k|ə|ˌ|m|oʊ|ʔ|oʊ|ə|ˈ|l|ɛ|v|ə}}<br />{{IPA|haw|kəˈmoʔowəˈlɛvə|lang}} | named_after = {{MoMP|469219|Ka mo{{okina}}o a lewa}}<br />{{small|("the oscillating fragment")}} | mp_category = {{Ubl | [[Near-Earth object|NEO]] | [[Apollo asteroid|Apollo]]<ref name="jpldata" /><ref name="MPC-object" /> | Earth [[quasi-satellite]]<ref name="de-la-Fuente-Marcos-2016" /><ref name="NASA-news" /> }} | orbit_ref = <ref name="jpldata" /> | epoch = 2024-Mar-31 ([[Julian day|JD]] 2460400.5) | uncertainty = 0 | observation_arc = 20.00 [[Julian year (astronomy)|yr]] (7,306 d) | aphelion = 1.10373 [[Astronomical unit|AU]] | perihelion = 0.89816 AU | semimajor = 1.00094 AU | eccentricity = 0.10269<br />(964 wrt Earth){{efn|name=geocentric}} | period = 1.0014 yr (365.77 d) | mean_anomaly = 175.153[[Degree (angle)|°]] | mean_motion = {{Deg2DMS|0.98422|sup=ms}} / day | inclination = 7.79605° | asc_node = 65.7907° | arg_peri = 305.0478° | moid = {{convert|0.0311|AU|LD|abbr=on}} | mean_diameter = {{Ubl | {{val|0.041|ul=km}} {{small|(calculated)}}<ref name="lcdb" /> | 0.04–0.10 km<ref name="NASA-news" /> }} | rotation = {{val|0.467|0.008|ul=h}}{{refn|group=lower-alpha|name=lcdb-Reddy-2018}} | albedo = 0.20 {{small|(assumed)}}<ref name="lcdb" /> | spectral_type = [[S-type asteroid|S]] {{small|(assumed)}}<ref name="lcdb" /> | abs_magnitude = {{Ubl | 24.33<ref name="jpldata" /><ref name="MPC-object" /> | 24.3<ref name="lcdb" /> }} }}
'''469219 Kamo{{okina}}oalewa''' ({{IPAc-en|k|ə|ˌ|m|oʊ|ʔ|oʊ|ə|ˈ|l|ɛ|v|ə}};<ref>{{cite news |url=https://imiloahawaii.org/news/a-hua-he-inoa-8e3ax |title=He Noi{{okina}}i Nowelo i ka {{okina}}Ike Ku{{okina}}una Hawai{{okina}}i o ka {{okina}}Ōnaeao |newspaper=[[{{okina}}Imiloa Astronomy Center]] |date=30 December 2018 |access-date=2024-04-29}}</ref> [[provisional designation in astronomy|provisional designation]] '''{{mp|2016 HO|3}}''') is a very small [[Apollo asteroid|Apollo-type]] [[near-Earth asteroid]] approximately {{convert|40-100|m|ft|abbr=off|sp=us}} in diameter. It is an elongated object that rapidly rotates every 28 minutes. At present it is a [[quasi-satellite]] of Earth, and currently the second-smallest, closest, and most stable known such quasi-satellite (after {{mpl|2023 FW|13}}).
Kamo{{okina}}oalewa was discovered by [[Pan-STARRS]] at [[Haleakala Observatory]] on 27 April 2016. It is the target of the [[China National Space Administration]]'s ''[[Tianwen-2]]'' mission, which is scheduled to visit the asteroid sometime in July 2026.<ref name="Spacecom-May2025"/><ref name="planetary-2026-calendar"/> ''Tianwen-2'' will retrieve samples from the surface of Kamo{{okina}}oalewa and is planned to return them to Earth in 2027.<ref name="Spacecom-May2025"/>
The object's Earth-like orbit, proximity to the Earth–Moon system, higher [[Extinction (astronomy)|spectral reddening]] relative to other asteroids, and similarity to space weathered lunar materials indicate that it is likely lunar [[ejecta]].<ref name=Sharkey2021/><ref name=spacecom20240423>{{cite news |first=Robert |last=Lea |title=Earth's weird 'quasi-moon' Kamo'oalewa is a fragment blasted out of big moon crater |date=2024-04-23 |work=Space.com |url=https://www.space.com/quasi-moon-kamooalewa-giant-lunar-impact |access-date=2024-04-24 }}</ref><ref name="Castro-Cisneros, J. D. 2023">Castro-Cisneros, J. D., Malhotra, R., & Rosengren, A. J. (2023). Lunar ejecta origin of near-Earth asteroid Kamo'oalewa is compatible with rare orbital pathways. Commun Earth Environ, 4(1), 372. https://doi.org/10.1038/s43247-023-01031-w</ref><ref name=Jiao/> However, it might also be an [[S-type asteroid|S-type]] or [[L-type asteroid|L-type]] asteroid.<ref name="Reddy, V. 2017">Reddy, V., Kuhn, O., Thirouin, A., Conrad, A., Malhotra, R., Sanchez, J., & Veillet, C. (2017). Ground-based Characterization of Earth Quasi Satellite (469219) 2016 HO3 49th AAS-DPS Meeting, https://ui.adsabs.harvard.edu/abs/2017DPS....4920407R/abstract</ref><ref name=Sharkey2021/><ref name="Fenucci, M. 2021">Fenucci, M., & Novaković, B. (2021). The Role of the [[Yarkovsky Effect]] in the Long-term Dynamics of Asteroid (469219) Kamo'oalewa. The Astronomical Journal, 162(6). https://doi.org/10.3847/1538-3881/ac2902</ref> Despite being most similar to [[Space weathering|weathered]] Apollo 14 and Luna 24 [[Lunar mare|Lunar Mare]] soils, it is suggested to be from the lunar far-side [[Lunar highland|highland crust]] crater, [[Giordano Bruno (crater)|Giordano Bruno]].<ref name=Jiao/>
Orbital similarities suggest it is likely a co-orbital pair with {{mpl|2000 WN|10}}<ref name="Dermawan, B. 2019">Dermawan, B. (2019). Temporal Earth Coorbital Types of Asteroid 2016 HO3. Paper No. 012038 6th International Conference on Mathematics & Natural Sciences 2019. IOP Publishing. DOI: 10.1088/1742-6596/1127/1/012038</ref> or a broken up set including the other NEOs {{mpl|2020 KZ|2}}, {{mpl|2020 PN|1}}, and {{mpl|2020 PP|1}}.<ref name=Sharkey2021/>
== Discovery and naming ==
Kamo{{okina}}oalewa was first spotted on 27 April 2016, by the [[Pan-STARRS]] 1 asteroid survey telescope on [[Haleakalā]], Hawaii, that is operated by the [[University of Hawaii]]'s Institute for Astronomy and funded by NASA's [[Planetary Defense Coordination Office]].<ref name="MPC-object" /><ref name="NASA-news" /> It was named {{MoMP|469219|Ka mo{{okina}}o a lewa}} in 2019, from the Hawaiian chant [[Kumulipo]] for an oscillating [[celestial object]] by [[A Hua He Inoa]] at the [[{{okina}}Imiloa Astronomy Center|'Imiloa Astronomy Center of Hawai'i]].<ref>M.P.C. (2019). The MINOR PLANET CIRCULARS/MINOR PLANETS AND COMETS. In (Vol. 112435): International Astronomical Union. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/2019/MPC_20190406.pdf</ref><ref>{{okina}}Imiloa. A Hua He Inoa Calling forth a name. https://imiloahawaii.org/a-hua-he-inoa</ref>
The name Kamo{{okina}}oalewa is derived from the Hawaiian words ''ka'' 'the', ''mo{{okina}}o'' 'fragment', referring to it being a piece broken off a larger object, ''a'' 'of', and ''lewa'' 'to oscillate', referring to its motion in the sky as viewed from Earth.<ref>{{Cite news|url=https://imiloahawaii.org/news/a-hua-he-inoa-8e3ax|title=A Hua He Inoa|website={{okina}}Imiloa Astronomy Center|date=30 December 2018 }}</ref><ref>ulukau HAWAIIAN ELECTRONIC LIBRARY</ref> The official {{MoMP|469219|naming citation}} was published by the [[Minor Planet Center]] on 6 April 2019 ([[Minor Planet Circulars|M.P.C.]] 112435).<ref name="MPC-Circulars-Archive" />
== Orbit and classification == [[File:2016 HO3 orbit_Jan2018.png|thumb|left|Orbit of Kamo{{okina}}oalewa in the [[inner Solar System]]]]
Kamo{{okina}}oalewa orbits the Sun at a distance of 0.90–1.10 [[Astronomical unit|AU]]. Although the period as of 2022 is about 366 days, its longer-term average period is closer to 365 days. Kamo{{okina}}oalewa is a quasi-moon and not gravitationally bound to Earth like a true satellite. Its orbit transfers between a [[Quasi-satellite|quasi satellite orbit]] type which resides in the {{L1|nolink=yes}} and {{L2|nolink=yes}} [[Lagrange point|Lagrange]] points, and a [[horseshoe orbit]] between the {{L4|nolink=yes}} and {{L5|nolink=yes}} Lagrange points.<ref name="Castro-Cisneros, J. D. 2023"/><ref name="Qiao, D. 2022">Qi, Y., & Qiao, D. (2022). Co-orbital transition of 2016 HO3. Astrodynamics, 7(1), 3-14. https://doi.org/10.1007/s42064-021-0122-0</ref>
Its orbit has an [[orbital eccentricity|eccentricity]] of 0.10 and an [[orbital inclination|inclination]] of 8[[Degree (angle)|°]] with respect to the [[ecliptic]].<ref name="jpldata" /> In March 2024, it had an Earth [[minimum orbital intersection distance]] of {{Convert|0.031|AU|e6km|abbr=unit|lk=on}} or 12 [[Lunar distance (astronomy)|lunar distances]],<ref name="jpldata" /> well outside of Earth's [[Hill sphere#Solar System|Hill sphere]] of {{Convert|1.5|e6km|LD|abbr=unit}}.
=== Quasi-satellite of Earth === {{stack|[[File:Asteroid2016HO3-SunEarthOrbit.webm|thumb|upright|The oscillating path of asteroid Kamo{{okina}}oalewa as it orbits around the Sun. The traced path of Kamo{{okina}}oalewa makes it appear as a constant companion of the Earth.]]}} In a rotating frame of reference Kamo{{okina}}oalewa appears to circle elliptically around the Earth every ~45 years.<ref>Chodas, P. (2016). The Orbit and Future Motion of Earth Quasi-Satellite 2016 HO3 AAS-DPS 48th Meeting, https://ui.adsabs.harvard.edu/abs/2016DPS....4831104C/abstract</ref> Although it is too distant to be considered a true [[natural satellite]] of Earth, it is the best and most stable example to date of a near-Earth companion, or [[quasi-satellite]].<ref name="de-la-Fuente-Marcos-2016" /> Orbital and Yarkovsky effect modeling suggest it will be stable for 0.3–0.5 million years.<ref name="Dermawan, B. 2019"/><ref name="Fenucci, M. 2021"/><ref name="Qiao, D. 2022"/>
Paul Chodas, manager of [[NASA]]'s [[Center for Near-Earth Object Studies]] (CNEOS) at the [[Jet Propulsion Laboratory]] (JPL) in [[Pasadena, California]] described the orbit of Kamo{{okina}}oalewa as a quasi-satellite of Earth. Unlike asteroid {{mpl|2003 YN|107}}, which previously followed a similar orbit, Kamo{{okina}}oalewa is more stable and has been Earth's companion for more than a century and will remain so for much longer. This asteroid spends half of its orbit closer to the Sun than Earth and the other half farther away, causing it to oscillate above and below Earth's orbit annually. Its orbit experiences slight drifts that Earth's gravity corrects, keeping it between 38 and 100 times the distance of the Moon. Thus, Kamo{{okina}}oalewa continually dances around the Earth.<ref name="NASA-news" />
The closest Earth approach was on {{start date and age|1923|12|27|df=y|paren=y}} at {{Convert|12.44|e6km|AU LD|abbr=unit|lk=on}}.<ref name="jpldata"/> By late May 2369, the asteroid will be {{Convert|2.0|AU|LD e6km|abbr=unit|lk=on}} from Earth.<ref name="Horizons2369"/> The Earth-like orbit may be a result of it being lunar ejecta.<ref name=Sharkey2021/> Most objects in this kind of orbit are eventually perturbed out of being in an Earth-co-orbital state and hit the Earth, Venus, or the Sun or are ejected from the [[Solar System]], and Kamo{{okina}}oalewa will probably hit the Earth in the next 100 million years.<ref name=Jiao/>
== Physical characteristics ==
The size of Kamo{{okina}}oalewa has not yet been firmly established, but it is approximately {{convert |40|–|100|m|ft|abbr=on}}.<ref name="NASA-news" /> Based on an assumed standard [[astronomical albedo|albedo]] for stony [[S-type asteroid]]s of 0.20, its [[absolute magnitude]] of 24.3 corresponds to {{convert|41|m|ft|sp=us}} in diameter.<ref name="lcdb" />
Photometric observations in April 2017 revealed that Kamo{{okina}}oalewa is a [[List of fast rotators (minor planets)|fast rotator]]. [[Lightcurve]] analysis gave a [[rotation period]] of {{convert |0.467|±|0.008 |hour|minute|abbr=off}} and a brightness variation of {{val|0.80|0.05}} [[Magnitude (astronomy)|magnitude]] ({{small|[[LCDB quality code|U=2]]}}).<ref name="lcdb" />{{refn|group=lower-alpha|name=lcdb-Reddy-2018}} 2024 inversion modeling was used to create a 100m x 81m x 46m (~72m diameter) 3D model from light curve data.<ref>Ren, J., Wu, B., Hesse, M. A., Li, H., Liu, Y., & Wang, X. (2024). Surface dynamics of small fast-rotating asteroids: Analysis of possible regolith on asteroid 2016 HO3. Astronomy & Astrophysics, 692. https://doi.org/10.1051/0004-6361/202451407</ref>
In 2021, a spectroscopic characterization of Kamo{{okina}}oalewa was conducted using the [[Large Binocular Telescope]] and the [[Lowell Discovery Telescope]], which found that the asteroid is likely silicate in origin. The object's Earth-like orbit, proximity to the Earth–Moon system, higher [[Space weathering#Space weathering on asteroids|spectral reddening]] to other asteroids, and similarity to space weathered lunar materials indicate that it is likely lunar [[ejecta]].<ref name=Sharkey2021/><ref name=spacecom20240423/><ref name="Castro-Cisneros, J. D. 2023"/><ref name=Jiao/> However, it might also be an [[S-type asteroid|S-type]] or [[L-type asteroid|L-type]] asteroid.<ref name="Reddy, V. 2017"/><ref name=Sharkey2021/><ref name="Fenucci, M. 2021"/> Despite being most similar to [[Space weathering|weathered]] Apollo 14 and Luna 24 [[Lunar mare|Lunar Mare]] soils, it is suggested to be from the lunar far-side [[Lunar highland|highland crust]] crater, [[Giordano Bruno (crater)|Giordano Bruno]] for its required size and [[Copernican period|Copernican]] age.<ref name=Jiao/>
Lunar ejecta modeling shows some avenues that can achieve a stable Kamo'oalewa-style quasi-satellite orbit.<ref>Winter, O., Moraes, R., Gomes, L., Sfair, R., & Borderes-Motta, G. (2022). On the possibility that 2016 HO3 Kamo'oalewa was a piece of the Moon 44th COSPAR Scientific Assembly, https://ui.adsabs.harvard.edu/abs/2022cosp...44..274W/abstract</ref><ref name="Castro-Cisneros, J. D. 2023"/><ref name=Jiao/>
== Exploration == === Tianwen-2 === {{main|Tianwen-2}} The [[China National Space Administration]] (CNSA) launched the ''[[Tianwen-2]]'' mission in May 2025 to [[Sample-return mission|return samples]] from Kamo{{okina}}oalewa.<ref>{{cite web |last1=Clark |first1=Stephen |title=China extends its reach into the Solar System with launch of asteroid mission |url=https://arstechnica.com/science/2025/05/china-extends-its-reach-into-the-solar-system-with-launch-of-asteroid-mission/ |website=Ars Technica |access-date=30 May 2025 |date=28 May 2025}}</ref><ref>{{cite journal |last1=Gibney |first1=Elizabeth |title=China plans mission to Earth's pet asteroid |journal=[[Nature (journal)|Nature]] |date=30 April 2019 |url=https://www.nature.com/articles/d41586-019-01390-5 |access-date=2024-04-29 |doi=10.1038/d41586-019-01390-5|pmid=32346150 |s2cid=155198626 |url-access=subscription }}</ref><ref>{{cite conference |last1=Zhang |first1=Xiaojing |last2=Huang |first2=Jiangchuan |last3=Wang |first3=Tong |last4=Huo |first4=Zhuoxi |url=https://www.hou.usra.edu/meetings/lpsc2019/pdf/1045.pdf |title=ZhengHe{{Snd}} A Mission to a Near-Earth Asteroid and a Main Belt Comet |conference=50th [[Lunar and Planetary Science Conference]] |date=18–22 March 2019 |access-date=2024-04-29 }}</ref> The spacecraft is scheduled to arrive at Kamoʻoalewa on June 7, 2026, spending several months surveying and imaging the asteroid, before collecting samples and departing in April 2027.<ref name="Spacecom-May2025"/><ref name="planetary-2026-calendar"/>
=== Proposed missions === Numerous mission concepts targeting Kamoʻoalewa have been proposed, including a 2019 NASA [[Solar sail|solar-sail]] mission concept,<ref name="doi.org">Heiligers, J., Fernandez, J. M., Stohlman, O. R., & Wilkie, W. K. (2019). Trajectory design for a solar-sail mission to asteroid 2016 HO3. Astrodynamics, 3(3), 231-246. https://doi.org/10.1007/s42064-019-0061-1</ref> a University of Colorado flyby and impact experiment,<ref>Venigalla, C., Baresi, N., Aziz, J. D., Bercovici, B., Brack, D. N., Dahir, A., De Smet, S., Fulton, J., Pellegrino, M. M., & Van wal, S. (2019). Near-Earth Asteroid Characterization and Observation (NEACO) Mission to Asteroid (469219) 2016 HO3. Journal of Spacecraft and Rockets, 56(4), 1121-1136. https://doi.org/10.2514/1.A34268</ref> and was selected as a target for the Chinese ZhengHe project,<ref>Jin, W., Li, F., Yan, J., Yang, X., Ye, M., Andert, T., & Peytavi, G. (2019). Simulation of global GM estimate of Asteroid (469219) 2016 HO3 for China's future asteroid mission EPSC-DPS, Geneva, CH</ref> which has developed into the [[Tianwen-2]] mission.<ref>Yan, J., Liu, L., Ye, M., Jin, W., Qiu, D., & Barriot, J.-P. (2022). A simulation of the joint estimation of the GM value and the ephemeris of the asteroid 2016 HO3. Icarus, 385. https://doi.org/10.1016/j.icarus.2022.115120</ref> The [[Chondrite|chondritic]] [[Regolith simulant|simulants]] QLS-1, 2, and 3 have been developed by the [[Qian Xuesen Laboratory of Space Technology]] to better prepare for these missions.<ref>Zhang, X., Luo, Y., Xiao, Y., Liu, D., Guo, F., & Guo, Q. (2021). Developing Prototype Simulants for Surface Materials and Morphology of Near Earth Asteroid 2016 HO3. Space: Science & Technology, 2021. https://doi.org/10.34133/2021/9874929</ref> In an ambitious proposal, Kamo{{okina}}oalewa is even considered for use as a space station for Earth-to-Mars travel.<ref name="ui.adsabs.harvard.edu">Fargion, D. (2022). Mini-moon, Kamo'oalewa: The Future Space Station 44th COSPAR Scientific Assemly, https://ui.adsabs.harvard.edu/abs/2022cosp...44..215F/abstract</ref>
During the 2017 Astrodynamics Specialist Conference held in [[Stevenson, Washington|Stevenson]] in the U.S. state of Washington, a team composed of graduate research assistants from the [[University of Colorado Boulder]] and the [[São Paulo State University]] (UNESP) was awarded for presenting a project denominated "Near-Earth Asteroid Characterization and Observation (NEACO) Mission to Asteroid (469219) {{mp|2016 HO|3}}", providing the first baselines for the investigation of this celestial object using a spacecraft.<ref>{{cite journal |last1=Venigalla |first1=C |last2=Baresi |first2=N |last3=Aziz |first3=J |last4=Bercovici |first4=B |last5=Borderes Motta |first5=G |last6=Brack |first6=D |last7=Cardoso dos Santos |first7=J |last8=Dahir |first8=A |last9=Davis |first9=A B |last10=Smet |first10= S D |display-authors=etal |title= Near-Earth Asteroid Characterization and Observation (NEACO) Mission to Asteroid (469219) 2016 HO3 |journal= Journal of Spacecraft and Rockets |volume=56 |issue=4 |pages=1121–1136 |url=https://unesp.br/Modulos/Noticias/32100/final_paper_aas-17-744-1.pdf |access-date=2024-04-29 |bibcode=2019JSpRo..56.1121V |doi=10.2514/1.A34268 |year=2019 |s2cid=126452156 }}</ref><ref>{{cite journal |last1=Venigala |first1= C |display-authors=etal |title=STUDENT DESIGN COMPETITION |journal=Space Times Magazine |url=https://astronautical.org/dev/wp-content/uploads/2017/11/ST56-5-September-October2017.pdf |date=September–October 2017 |access-date=2024-04-29 }}</ref><ref>{{cite journal |last1=Cardoso dos Santos |first1=J |last2=Borderes Motta |first2=G |title= Alunos da Unesp vencem competição internacional |journal=UNESP Notícias (Portuguese) |url=https://www2.unesp.br/portal#!/noticia/32100/alunos-da-unesp-vencem-competicao-internacional/ |date=March 2018 |access-date=2024-04-29 }}</ref> Recently, another version of this work was presented adopting different constraints in the dynamics.<ref>{{cite journal |last1=Venigalla |first1=C |last2=Baresi |first2=N |last3=Aziz |first3=J |last4=Bercovici |first4=B |last5=Brack |first5=D |last6=Dahir |first6=A |last7=Davis |first7=A B |last8=Smet |first8= S D |display-authors=etal |title= Near-Earth Asteroid Characterization and Observation (NEACO) Mission to Asteroid (469219) 2016 HO3 |journal=[[Journal of Spacecraft and Rockets]] |volume=56 |issue=4 |pages=1121–1136 |date=February 2019 |doi=10.2514/1.A34268 |bibcode=2019JSpRo..56.1121V |s2cid=126452156 }}</ref>
== Gallery ==
{{multiple image | align = center | direction = horizontal | width = 235 | header = Animation of the orbit of Kamo{{okina}}oalewa from 2000 to 2300, showing quasi-satellite phase | image1 = Animation of 2016 HO3 orbit relative to Sun-Earth 2000-2300.gif | caption1 = Relative to Sun and Earth (rotating frame of reference) | image2 = Animation of 2016 HO3 orbit around Earth 2000-2300.gif | caption2 = Around Earth (non-rotating frame) | image3 = Animation of 2016 HO3 orbit around Sun 2000-2300.gif | caption3 = Around Sun (non-rotating frame) | footer = {{legend2| Yellow| Sun}}{{·}}{{legend2| RoyalBlue| Earth}}{{·}}{{legend2|Magenta| 469219 Kamo'oalewa}} | total_width = | alt1 = }}
{{multiple image | align = center | direction = horizontal | width = 235 | header = Animation of the orbit of Kamo{{okina}}oalewa from 1600 to 2500, going from horseshoe orbit to quasi-satellite and back | image1 = Animation of 2016 HO3 orbit relative to Sun-Earth.gif | caption1 = Relative to Sun and Earth (rotating frame of reference) | image2 = Animation of 2016 HO3 orbit around Earth.gif | caption2 = Around Earth (non-rotating frame) | image3 = Animation of 2016 HO3 orbit around Sun.gif | caption3 = Around Sun (non-rotating frame) | footer = {{legend2| Yellow| Sun}}{{·}}{{legend2| RoyalBlue| Earth}}{{·}}{{legend2|Magenta| 469219 Kamo'oalewa}} | total_width = | alt1 = }} {{clear}}
== See also == {{Div col|colwidth=15em}} * [[Arjuna asteroid]] * [[3753 Cruithne]] * [[6Q0B44E]] * {{mpl|2001 GO|2}} * {{mpl|2002 AA|29}} * {{mpl|2003 YN|107}} * {{mpl|164207 Cardea}} * {{mpl|2006 JY|26}} * {{mpl|2006 RH|120}} * {{mpl|2012 FC|71}} * {{mpl|2013 BS|45}} * {{mpl|(419624) 2010 SO|16}} * {{mpl|(436724) 2011 UW|158}} * {{mpl|524522 Zoozve}}, a quasi-satellite of Venus, and the first quasi-satellite discovered around any major planet {{Div col end}}
== Notes == {{notelist |refs=
{{refn|group=lower-alpha|name=lcdb-Reddy-2018|1=Exceptional rotation period of {{convert|0.467|±|0.008|hour|minute|abbr=off}} with a brightness amplitude of {{val|0.80|0.05}} mag, quality code = 2, based on summary figures at the [[Light curve#Asteroid lightcurve database|LCDB]], which references (Reddy 2018).<ref name="lcdb" /> Relevant abstract in ADS is (Reddy 2017).<ref name="Reddy2017" />}}
{{efn|name=geocentric|1=Computed with [https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%27469219%27&TABLE_TYPE=%27ELEMENTS%27&START_TIME=%272024-Mar-31%27&STOP_TIME=%272100-Jan-01%27&STEP_SIZE=%27100%20years%27 JPL Horizons] using a geocentric solution. Ephemeris Type: Orbital Elements / Center: 500 / Time Span: 2022-Jan-21 (to match infobox epoch)}}
}} <!-- end of notelist -->
== References == {{reflist|30em|refs=
<ref name="jpldata">{{cite web |type = 2024-03-18 last obs. |title = JPL Small-Body Database Browser: 469219 Kamo'oalewa (2016 HO3) |url = https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2469219&view=OPC |publisher = [[Jet Propulsion Laboratory]] |access-date = 29 April 2024}}</ref>
<ref name="MPC-object">{{cite web |title = (469219) Kamo{{okina}}oalewa = 2016 HO3 |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=469219 |access-date = 29 April 2024}}</ref>
<ref name="MPC-Circulars-Archive">{{cite web |title = MPC/MPO/MPS Archive |work = Minor Planet Center |url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html |access-date = 29 April 2024}}</ref>
<ref name="lcdb">{{cite LCDB|number = 469219 |website = MinorPlanet.Info — ALCDEF Query |access-date = 29 April 2024}}</ref>
<ref name="Reddy2017">{{cite journal |last1=Reddy |first1=Vishnu |last2=Kuhn |first2=Olga |last3=Thirouin |first3=Audrey |last4=Conrad |first4=Al |last5=Malhotra |first5=Renu |last6=Sanchez |first6=Juan A. |last7=Veillet |first7=Christian |display-authors=3 |title=Ground-based Characterization of Earth Quasi Satellite (469219) 2016 HO3 |journal=AAS DPS Meeting |volume=49 |at=id.204.07 |date=October 2017 |publisher=[[American Astronomical Society]] |bibcode=2017DPS....4920407R}}</ref>
<ref name="NASA-news">{{cite web |last1 = Agle |first1=DC |last2 = Brown |first2=Dwayne |last3 = Cantillo |first3=Laurie |title = Small Asteroid Is Earth's Constant Companion |date = 15 June 2016 |publisher = Jet Propulsion Laboratory |url = https://www.jpl.nasa.gov/news/news.php?feature=6537 |access-date = 29 April 2024}}</ref>
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}} <!-- end of reflist -->
== External links == {{Commons category}} * [https://www.youtube.com/watch?v=zMJc7gmychk Asteroid 2016 HO3 - Earth's Constant Companion] NASA Jet Propulsion Laboratory, 23 June 2016 * {{NeoDys|469219}} * {{ESA-SSA|469219|2016HO3}} * {{JPL small body}}
{{2016 in space}} {{2026 in space}} {{Minor planets navigator | |number=469219 | }} {{Small Solar System bodies}} {{portal bar|Astronomy|Solar System}} {{Authority control}}
{{DEFAULTSORT:Kamo'oalewa}} [[Category:Apollo asteroids|469219]] [[Category:Discoveries by Pan-STARRS|469219]] [[Category:Named minor planets]] [[Category:Earth co-orbital asteroids|469219]] [[Category:Fast rotating minor planets|469219]] [[Category:Astronomical objects discovered in 2016|20160427]] [[Category:Minor planets to be visited by spacecraft]]