View source for Astronomy:WASP-107b

{{Short description|Super Neptune orbiting WASP-107}}
{{Infobox planet
| name                     = WASP-107b
| image                    = Artist’s impression of WASP-107b.jpg
| caption                  = Artist's impression of exoplanet WASP-107b.<ref>{{cite web|title=Hubble detects helium in the atmosphere of an exoplanet for the first time|url=https://www.spacetelescope.org/news/heic1809/|author=heic1809|website=www.spacetelescope.org|date=2 May 2018|access-date=4 May 2018}}</ref>
<!-- DISCOVERY           -->
| discoverer               = D. R. Anderson et al.
| discovered               = 2017
| discovery_method         = [[Astronomy:Wide Angle Search for Planets|WASP-South]]
<!-- DESIGNATIONS        -->
<!-- ORBITAL             --> 
| apsis                    = astron
| semimajor                = {{convert|0.0566|±|0.0017|AU|km|abbr=on}}<ref name=Piaulet2020/>
| eccentricity             = 0<ref name=Exoplanet.eu>{{Cite web|title=Planet WASP-107 b|url=https://exoplanet.eu/catalog/wasp_107_b--6505/|work=[[Astronomy:Extrasolar Planets Encyclopaedia|Extrasolar Planets Encyclopaedia]]|year=2017}}</ref>
| period                   = 5.7214742 [[Day|d]]<ref name=Piaulet2020/>
| star                     = WASP-107
<!-- PHYS CHARS          --> 
| mean_radius              = 0.96{{±|0.03}} {{Jupiter radius|link=y}}<ref name=Piaulet2020/>
<!-- ATMOSPHERE          --> 
<!-- NOTES               --> 
}}
'''WASP-107b''' is a [[Astronomy:Super-Neptune|super-Neptune]] [[Astronomy:Exoplanet|exoplanet]] that orbits the star WASP-107. It lies 200 light-years away from [[Astronomy:Earth|Earth]] in the constellation [[Astronomy:Virgo (constellation)|Virgo]].<ref name=Space>{{Cite web|last1=Reed|first1=Nola|title=An Exoplanet First! Helium Spotted on Bizarre Comet-Like World|url=https://www.space.com/40469-helium-detected-alien-planet-atmosphere.html|website=Space.com|date=2 May 2018}}</ref> Its discovery was announced in 2017 by a team led by D. R. Anderson via the [[Astronomy:Wide Angle Search for Planets|WASP-South]].<ref>{{cite journal |first1=D.R. |last1=Anderson |first2=A. Collier |last2=Cameron |display-authors=0 |title=The discoveries of WASP-91b, WASP-105b and WASP-107b: Two warm Jupiters and a planet in the transition region between ice giants and gas giants |url=https://www.aanda.org/articles/aa/pdf/2017/08/aa30439-17.pdf |journal=Astronomy & Astrophysics |volume=604 |number=A110 |date=August 2017 |pages=A110 |doi=10.1051/0004-6361/201730439|arxiv=1701.03776 |bibcode=2017A&A...604A.110A |s2cid=58910823 }}</ref>

== Planetary orbit==
WASP-107b could not have formed in its current orbit. It likely migrated inward from its birth orbit beyond 1 [[Astronomy:Astronomical unit|AU]] due to interaction with the heavier planet WASP-107c. It is in a retrograde orbit, strongly misaligned with the equatorial plane of the parent star. The misalignment angle is equal to 118°{{±|38|19}}.<ref>{{citation|arxiv=2101.09371|title=The TESS–Keck Survey. IV. A Retrograde, Polar Orbit for the Ultra-low-density, Hot Super-Neptune WASP-107b|year=2021|doi=10.3847/1538-3881/abd177 |last1=Rubenzahl |first1=Ryan A. |last2=Dai |first2=Fei |last3=Howard |first3=Andrew W. |last4=Chontos |first4=Ashley |last5=Giacalone |first5=Steven |last6=Lubin |first6=Jack |last7=Rosenthal |first7=Lee J. |last8=Isaacson |first8=Howard |last9=Batalha |first9=Natalie M. |last10=Crossfield |first10=Ian J. M. |last11=Dressing |first11=Courtney |last12=Fulton |first12=Benjamin |last13=Huber |first13=Daniel |last14=Kane |first14=Stephen R. |last15=Petigura |first15=Erik A. |last16=Robertson |first16=Paul |last17=Roy |first17=Arpita |last18=Weiss |first18=Lauren M. |last19=Beard |first19=Corey |last20=Hill |first20=Michelle L. |last21=Mayo |first21=Andrew |last22=Mocnik |first22=Teo |last23=Murphy |first23=Joseph M. Akana |last24=Scarsdale |first24=Nicholas |journal=The Astronomical Journal |volume=161 |issue=3 |page=119 |bibcode=2021AJ....161..119R |s2cid=231698426 |doi-access=free }}</ref> WASP-107c follows a highly eccentric and inclined orbit with a period of 1088{{±|15|16}} [[Day|day]]s.<ref name=Piaulet2020/>

== Physical characteristics ==
WASP-107b is a [[Astronomy:Super-Neptune|super-Neptune]] [[Astronomy:Ice giant|ice giant]] [[Astronomy:Exoplanet|exoplanet]] located 200 light years away from [[Astronomy:Earth|Earth]] in the [[Astronomy:Virgo (constellation)|constellation Virgo]].<ref name=Space/> It is roughly the size of [[Astronomy:Jupiter|Jupiter]] but less than one-tenth of Jupiter's mass, making it one of the lowest density exoplanets.<ref name=Piaulet2020/> Its radius is 0.96{{±|0.03}} times Jupiter's, making its atmosphere fluffy, and coupled with transiting a moderately bright K-type star, makes it a target for atmospheric characterization.<ref name=WASP-Planets>{{Cite web|title=First results on the atmosphere of WASP-107b|url=https://wasp-planets.net/2017/09/27/first-results-on-the-atmosphere-of-wasp-107b/|publisher=[[Astronomy:Wide Angle Search for Planets|Wide Angle Search for Planets]]|date=September 27, 2017}}</ref> It is eight times nearer to its star than [[Astronomy:Mercury (planet)|Mercury]] is to the [[Astronomy:Sun|Sun]] and orbits its star every 5.7 days.<ref name=Space/> With a temperature of {{convert|500|C}}, its atmosphere makes it one of the hottest known exoplanets.<ref name=Space/>

[[Chemistry:Helium|Helium]] was discovered in the planet's atmosphere in 2018, making it the first time helium was discovered on an exoplanet.<ref name=Nature>{{cite journal|last1=Witze|first1=Alexandra|title=Astronomers spot helium on exoplanet for first time|url=https://www.nature.com/articles/d41586-018-05052-w|journal=Nature|date=2 May 2018|doi=10.1038/d41586-018-05052-w}}</ref> A follow-up observation with [[Astronomy:W. M. Keck Observatory|Keck]] in 2020 showed that the helium absorption extends beyond transit-egress.<ref name=":1">{{cite journal|last1=Kirk|first1=James|last2=Alam|first2=Munazza K.|last3=Lopez-Morales|first3=Mercedes|last4=Zeng|first4=Li|date=2020-01-21|title=Confirmation of WASP-107b's extended Helium atmosphere with Keck II/NIRSPEC|journal=The Astronomical Journal|volume=159|issue=3|pages=115|doi=10.3847/1538-3881/ab6e66|arxiv=2001.07667|bibcode=2020AJ....159..115K |s2cid=210838904 |doi-access=free }}</ref> [[Physics:Extreme ultraviolet|Extreme ultraviolet]] radiation from the host star is gradually whittling down the planet's atmosphere, forming a comet-like tail 7 times as long as the radius of the planet.<ref name=":0">{{Cite web|url=https://wasp-planets.net/2020/01/22/helium-reveals-the-extended-atmosphere-of-wasp-107b/|title=Helium reveals the extended atmosphere of WASP-107b|last=waspplanets|date=2020-01-22|website=WASP Planets|language=en|access-date=2020-01-22}}</ref><ref>{{citation|arxiv=2107.08999|year=2021|title=The Posttransit Tail of WASP-107b Observed at 10830 Å|doi=10.3847/1538-3881/ac178a |last1=Spake |first1=J. J. |last2=Oklopčić |first2=A. |last3=Hillenbrand |first3=L. A. |journal=The Astronomical Journal |volume=162 |issue=6 |page=284 |bibcode=2021AJ....162..284S |s2cid=236087427 |doi-access=free }}</ref>

In November 2023, scientists discovered that its atmosphere contains water vapor and [[Chemistry:Sulfur dioxide|sulfur dioxide]]. The clouds on this planet are made up of [[Chemistry:Silicate mineral|silicates]].<ref>{{cite web |url=https://www.npr.org/2023/11/15/1213159944/clouds-made-of-sand-make-for-a-strange-kind-of-rain-on-this-hot-planet|title=Clouds made of sand make for a strange kind of rain on this hot planet |website=NPR News |access-date=16 November 2023}}</ref><ref>{{Cite journal |last1=Dyrek |first1=Achrène |last2=Min |first2=Michiel |last3=Decin |first3=Leen |last4=Bouwman |first4=Jeroen |last5=Crouzet |first5=Nicolas |last6=Mollière |first6=Paul |last7=Lagage |first7=Pierre-Olivier |last8=Konings |first8=Thomas |last9=Tremblin |first9=Pascal |last10=Güdel |first10=Manuel |last11=Pye |first11=John |last12=Waters |first12=Rens |last13=Henning |first13=Thomas |last14=Vandenbussche |first14=Bart |last15=Ardevol Martinez |first15=Francisco |date=2023-11-15 |title=SO2, silicate clouds, but no CH4 detected in a warm Neptune |url=https://www.nature.com/articles/s41586-023-06849-0 |journal=Nature |pages=1–3 |language=en |doi=10.1038/s41586-023-06849-0 |pmid=37967578 |arxiv=2311.12515 |s2cid=265219725 |issn=0028-0836}}</ref>

== See also ==
* [[Astronomy:Lists of exoplanets|Lists of exoplanets]]
* [[Astronomy:List of largest exoplanets|List of largest exoplanets]]
* [[Astronomy:List of nearest exoplanets|List of nearest exoplanets]]

== References ==
{{reflist}}

== External links ==
{{2017 in space}}
{{Stars of Virgo}}

[[Category:Virgo (constellation)]]
[[Category:Gas giants]]
[[Category:Giant planets]]
[[Category:Hubble Space Telescope]]
[[Category:Helium]]

{{Sourceattribution|WASP-107b}}