{{Short description|Gas giant}} {{Infobox planet | name = 2M0437b <!-- DISCOVERY -->| discoverer = Gaidos et al. | discovery_site = Subaru Telescope, Hawaii, USA | discovered = October 2021 | discovery_method = Imaged | discovery_ref = <ref name=Gaidos>{{cite journal|doi=10.1093/mnras/stab3069|title=Zodiacal exoplanets in time (ZEIT) XII: A directly imaged planetary-mass companion to a young Taurus M dwarf star |year=2022 |last1=Gaidos |first1=E. |last2=Hirano |first2=T. |last3=Kraus |first3=A. L. |last4=Kuzuhara |first4=M. |last5=Zhang |first5=Z. |last6=Lee |first6=R. A. |last7=Salama |first7=M. |last8=Berger |first8=T. A. |last9=Grunblatt |first9=S. K. |last10=Ansdell |first10=M. |last11=Liu |first11=M. C. |last12=Harakawa |first12=H. |last13=Hodapp |first13=K. W. |last14=Jacobson |first14=S. |last15=Konishi |first15=M. |last16=Kotani |first16=T. |last17=Kudo |first17=T. |last18=Kurokawa |first18=T. |last19=Nishikawa |first19=J. |last20=Omiya |first20=M. |last21=Serizawa |first21=T. |last22=Tamura |first22=M. |last23=Ueda |first23=A. |last24=Vievard |first24=S. |journal=Monthly Notices of the Royal Astronomical Society |volume=512 |pages=583–601 |doi-access=free |arxiv=2110.08655 }}</ref> <!-- DESIGNATIONS -->| exosolar planets = | extrasolarplanet = yes <!-- ORBITAL -->| alt_names = 2MASS J04372171+2651014 b | orbit_ref = | orbit_diagram = | epoch = | uncertainty = | observation_arc = | earliest_precovery_date = | apsis = astron | aphelion = | perihelion = | semimajor = {{convert|118|±|1.3|AU|km|abbr=on}}<ref name=Gaidos/> | mean_orbit_radius = | eccentricity = | period = | synodic_period = | avg_speed = | mean_anomaly = | mean_motion = | inclination = | angular_dist = | asc_node = | long_periastron = | time_periastron = | arg_peri = | semi-amplitude = <!-- PHYS CHARS --> | physical_ref = | dimensions = | mean_diameter = | mean_radius = | equatorial_radius = | polar_radius = | flattening = | circumference = | surface_area = | volume = | mass = 3-5<ref name=Gaidos/> {{Jupiter mass|link=y}} | density = | surface_grav = 3.6<ref name="Gaidos 2023"/> | moment_of_inertia_factor = | escape_velocity = | rotation = | sidereal_day = | rot_velocity = | axial_tilt = | albedo = | single_temperature = ~1200 K<ref name="Gaidos 2023"/> | spectral_type = | magnitude = | abs_magnitude = | angular_size = | family = | note = }} '''2M0437 b''', or 2MASS J04372171+2651014 b, is an extrasolar plane<nowiki/>t that orbits the pre-main sequence red dwarf 2MASS J04372171+2651014, 418 light-years away in the constellation of Taurus. It is a gas giant, with a mass 4 times that of Jupiter. It is one of the few exoplanets directly imaged. The planet is of importance to astronomers as it challenges models of planet formation by nucleus accretion and disk instability.<ref>{{Cite web |last= |first= |date=2021-10-22 |title=Infant planet discovered by UH-led team using Maunakea telescopes |url=https://www.hawaii.edu/news/2021/10/22/infant-planet-discovered-2m0437b/ |access-date=2021-11-22 |website=University of Hawai'i News |language=en-US}}</ref><ref>{{Cite encyclopedia|title=The Extrasolar Planet Encyclopaedia — 2M0437 b|url=https://exoplanet.eu/catalog/2m0437_b--7993/|encyclopedia=Extrasolar Planets Encyclopaedia|access-date=2021-11-22}}</ref>

== Star == The host star is a low mass red dwarf star (a mass of 0.15-0.18 solar masses) that belongs to the pre-main sequence with a temperature of 3100 K.<ref name=Gaidos/> Although K2 detected a quasiperiodic dimming of nearby circumstellar dust, the star it lacks an excess infrared emission detectable from a circumstellar disk and its Hα emission is not proportional to accretion. There is also evidence of a second extremely faint object 75 arc-seconds apart that is possibly linked to the star.<ref>{{Cite web|last=Carter|first=Jamie|title=An Alien Planet Has Been Photographed: Youngest Planet Ever Found Joins 'Elite List' Say Scientists|url=https://www.forbes.com/sites/jamiecartereurope/2021/10/25/an-alien-planet-has-been-photographed-youngest-planet-ever-found-joins-elite-list-say-scientists/|access-date=2021-11-22|website=Forbes|language=en}}</ref>

== Discovery == 2M0437 b was first observed in March 2018 in images from the Subaru Telescope. The observations required three years to confirm that the observed object was not a background star since the star has a very slow apparent movement across the sky.<ref>{{Cite web|date=2021-10-25|title=An 'Infant' Planet Could Shed Light on the Formation of the Solar System|url=https://interestingengineering.com/an-infant-planet-could-shed-light-on-the-formation-of-the-solar-system|access-date=2021-11-22|website=interestingengineering.com|language=en-US}}</ref>

== Characteristics == It is a super-Jupiter-type planet with a mass of 4 or 5 times that of Jupiter, at a distance of 118 AU from its star and an age between 2 and 5 million years. It is one of the youngest planets discovered. Together with their star they belong to a 1 to 5 million year old Taurus star formation region. Its effective temperature of ~ 1450 K gives it a spectrum of the L8-9 spectral type.<ref>{{Cite web|title=Rare Direct Image Of An Exoplanet Might Be The Youngest Ever Found|url=https://www.iflscience.com/space/rare-detet-image-of-an-exoplanet-might-be-the-youngest-ever-found/|access-date=2021-11-22|website=IFLScience|date=25 October 2021 |language=en}}</ref> Follow-up near-infrared (1-2.4 μm) spectroscopy with Subaru and Keck-1 detected carbon monoxide and possibly water vapor and methane in the atmosphere of 2M0437b. The absence or attenuation of spectral features at shorter wavelengths suggests the presence of micron-size dust.<ref name="Gaidos 2023">{{Cite journal |last1=Gaidos |first1=Eric |last2=Hirano |first2=Teruyuki |date=2023-11-01 |title=CO, H2O, and CH4 in the dusty atmosphere of a ≲5 Myr-old exoplanet |journal=Monthly Notices of the Royal Astronomical Society |volume=525 |issue=4 |pages=6303–6311 |doi=10.1093/mnras/stad2664 |doi-access=free |bibcode=2023MNRAS.525.6303G |issn=0035-8711}}</ref>

== See also ==

* List of exoplanets discovered in 2021

==References== {{Reflist}}{{Taurus (constellation)}} Category:Exoplanets discovered in 2021 Category:Exoplanets detected by direct imaging Category:Gas giants