WASP-121

{{Starbox begin

| name = WASP-121 / Dilmun

}}

{{Starbox observe

| epoch = J2000.0

| constell = Puppis

| ra = {{RA|07|10|24.06046}}

| dec = {{DEC|−39|05|50.5712}}

| appmag_v = 10.4

}}

{{Starbox character

| type = main sequence

| class = F6V

| appmag_1_passband = B

| appmag_1 = 11.00

| appmag_2_passband = V

| appmag_2 = 10.51

| appmag_3_passband = J

| appmag_3 = 9.625

| appmag_4_passband = H

| appmag_4 = 9.439

| appmag_5_passband = K

| appmag_5 = 9.374

| variable =

}}

{{Starbox astrometry

| radial_v = {{val|38.25|0.22}}

| prop_mo_ra = −3.735

| prop_mo_dec = 25.663

| pm_footnote =

| parallax = 3.7996

| p_error = 0.0104

| parallax_footnote =

| absmag_v =

}}

{{Starbox detail

| source =

| age_gyr = {{val|1.11|0.14}}

| metal_fe = +{{val|0.17|0.05}}

| mass = {{val|1.330|0.019}}

| radius = {{val|1.461|0.015}}

| gravity = {{val|4.251|0.003}}

| rotation =

| luminosity =

| temperature = {{val|6628|66|fmt=commas}}

| rotational_velocity =11.90{{±|0.31}}

}}

{{Starbox catalog

| names = {{odlist | name = Dilmun | CD = -38 3220 | TYC = 7630-352-1 | WASP = 121 | 2MASS = J07102406-3905506 | 1SWASP = J071024.05-390550.5 | TOI = 495 }}

}}

{{Starbox reference

| Simbad = WASP-121

| EPE = WASP-121

}}

WASP-121, also known as CD-38 3220 and formally named Dilmun,{{Cite web |title=2022 Approved Names |url=https://nameexoworlds.iau.org/2022approved-names |access-date=2024-07-22 |website=NameExoworlds |language=en}} is a magnitude 10.4 star located approximately {{convert|858|ly|pc|lk=on|abbr=off}} away in the constellation Puppis. WASP-121 has a mass and radius similar to the Sun's. It hosts one known exoplanet.

The star, although metal-rich in terms of overall contents of heavy elements, is depleted of carbon. The carbon to oxygen molar ratio of 0.23{{±|0.05}} for WASP-121 is well below the solar ratio of 0.55.{{citation|arxiv=2207.13662|year=2022|title=Chemical Abundances for 25 JWST Exoplanet Host Stars with KeckSpec|last1=Polanski |first1=Alex S. |last2=Crossfield |first2=Ian J. M. |last3=Howard |first3=Andrew W. |last4=Isaacson |first4=Howard |last5=Rice |first5=Malena |journal=Research Notes of the American Astronomical Society |volume=6 |issue=8 |page=155 |doi=10.3847/2515-5172/ac8676 |doi-access=free |bibcode=2022RNAAS...6..155P }}

Nomenclature

The designation WASP-121 indicates that this was the 121st star found to have a planet by the Wide Angle Search for Planets.

In August 2022, this planetary system was included among 20 systems to be named by the third NameExoWorlds project.{{cite web |url=https://www.nameexoworlds.iau.org/2022exoworlds |title=List of ExoWorlds 2022 |date=8 August 2022 |website=nameexoworlds.iau.org |publisher=IAU |access-date=27 August 2022}} The approved names, proposed by a team from Bahrain, were announced in June 2023. WASP-121 is named Dilmun after the ancient civilization, and its planet is named Tylos after the ancient Greek name for Bahrain.

Planetary system

In 2015, the exoplanet WASP-121b was discovered orbiting WASP-121 by the transit method.{{citation|arxiv=1506.02471|year=2015|title=WASP-121 b: A hot Jupiter close to tidal disruption transiting an active F star|doi=10.1093/mnras/stw522|last1=Delrez|first1=L.|last2=Santerne|first2=A.|last3=Almenara|first3=J.-M.|last4=Anderson|first4=D. R.|last5=Collier-Cameron|first5=A.|last6=Díaz|first6=R. F.|last7=Gillon|first7=M.|last8=Hellier|first8=C.|last9=Jehin|first9=E.|last10=Lendl|first10=M.|last11=Maxted|first11=P. F. L.|last12=Neveu-Vanmalle|first12=M.|last13=Pepe|first13=F.|last14=Pollacco|first14=D.|last15=Queloz|first15=D.|last16=Ségransan|first16=D.|last17=Smalley|first17=B.|last18=Smith|first18=A. M. S.|last19=Triaud|first19=A. H. M. J.|last20=Udry|first20=S.|last21=Van Grootel|first21=V.|last22=West|first22=R. G.|journal=Monthly Notices of the Royal Astronomical Society|volume=458|issue=4|pages=4025–4043|doi-access=free }} WASP-121b is a hot Jupiter with a mass about 1.18 times that of Jupiter and a radius about 1.81 times that of Jupiter. The exoplanet orbits WASP-121, its host star, every 1.27 days. Hot water molecules have been found in the stratosphere of WASP-121b (i.e., the atmospheric layer in which temperatures increase as the altitude increases).{{cite journal|arxiv=2005.09631|last1=Mikal-Evans|first1=Thomas|last2=Sing|first2=David K.|last3=Kataria|first3=Tiffany|last4=Wakeford|first4=Hannah R.|last5=Mayne|first5=Nathan J.|last6=Lewis|first6=Nikole K.|last7=Barstow|first7=Joanna K.|last8=Spake|first8=Jessica J.|title=Confirmation of water emission in the dayside spectrum of the ultrahot Jupiter WASP-121b|journal=Monthly Notices of the Royal Astronomical Society|year=2020|volume=496|issue=2|pages=1638–1644|doi=10.1093/mnras/staa1628|doi-access=free |s2cid=218684532}}

{{OrbitboxPlanet begin

|table_ref=

}}

{{OrbitboxPlanet

| exoplanet = b / Tylos

| mass = {{val|1.170|0.043}}

| period = 1.275

| semimajor = {{val|0.02571|0.00010}}

| eccentricity = 0.0

| inclination = 87.6

| radius = {{val|1.742|0.006}}

}}

Gallery

PIA22565-Exoplanet-WASP121b-ComputerSimViews-20180809.jpg|{{center|WASP-121b – computer-simulated views (August 2018)}}

HD189733b.jpg|An artist's impression of a hot Jupiter planet

References

{{Reflist|refs=

{{cite simbad

| title=WASP-121

| access-date=3 August 2017 }}

{{cite web |author=Staff |title=WASP Planets |url=https://wasp-planets.net/wasp-planets/ |date=2017 |work=wasp-planets.net |access-date=3 August 2017 }}

{{cite encyclopedia |author=Staff |title=Planet WASP-121 b |url=https://exoplanet.eu/catalog/wasp_121_b--2410/ |date=2015 |encyclopedia=Extrasolar Planets Encyclopaedia |access-date=3 August 2017 }}

{{cite web |last1=Landau |first1=Elizabeth |last2=Villard |first2=Ray |title=Hubble Detects Exoplanet with Glowing Water Atmosphere |url=https://www.jpl.nasa.gov/news/news.php?feature=6909 |date=2 August 2017 |work=NASA |access-date=2 August 2017 }}

{{cite journal |author=Evans, Thomas M.|display-authors=etal |title=An ultrahot gas-giant exoplanet with a stratosphere |date=2 August 2017 |journal=Nature |volume=548 |issue=7665 |pages=58–61 |doi=10.1038/nature23266 |arxiv = 1708.01076 |bibcode = 2017Natur.548...58E |pmid=28770846|s2cid=205258293 }}

{{citation|arxiv=2011.01245|title=Atmospheric Rossiter–Mc Laughlin effect and transmission spectroscopy of WASP-121b with ESPRESSO|year=2021|last1=Borsa|first1=F.|last2=Allart|first2=R.|last3=Casasayas-Barris|first3=N.|last4=Tabernero|first4=H.|last5=Zapatero Osorio|first5=M. R.|last6=Cristiani|first6=S.|last7=Pepe|first7=F.|last8=Rebolo|first8=R.|last9=Santos|first9=N. C.|last10=Adibekyan|first10=V.|last11=Bourrier|first11=V.|last12=Demangeon|first12=O. D. S.|last13=Ehrenreich|first13=D.|last14=Pallé|first14=E.|last15=Sousa|first15=S.|last16=Lillo-Box|first16=J.|last17=Lovis|first17=C.|last18=Micela|first18=G.|last19=Oshagh|first19=M.|last20=Poretti|first20=E.|last21=Sozzetti|first21=A.|last22=Allende Prieto|first22=C.|last23=Alibert|first23=Y.|last24=Amate|first24=M.|last25=Benz|first25=W.|last26=Bouchy|first26=F.|last27=Cabral|first27=A.|last28=Dekker|first28=H.|last29=D'Odorico|first29=V.|last30=Di Marcantonio|first30=P.|journal=Astronomy & Astrophysics|volume=645|pages=A24|doi=10.1051/0004-6361/202039344|bibcode=2021A&A...645A..24B|s2cid=226237425|display-authors=29}}

{{cite web |url=https://www.nameexoworlds.iau.org/2022approved-names |title=2022 Approved Names |website=nameexoworlds.iau.org |publisher=IAU |access-date=7 June 2023}}

{{Cite journal |last1=Sing |first1=David K. |last2=Evans-Soma |first2=Thomas M. |last3=Rustamkulov |first3=Zafar |last4=Lothringer |first4=Joshua D. |last5=Mayne |first5=Nathan J. |last6=Schlaufman |first6=Kevin C. |date=November 2024 |title=An Absolute Mass, Precise Age, and Hints of Planetary Winds for WASP-121A and b from a JWST NIRSpec Phase Curve |journal=The Astronomical Journal |language=en |volume=168 |issue=6 |pages=231 |doi=10.3847/1538-3881/ad7fe7 |doi-access=free |issn=1538-3881|arxiv=2501.03844 }}

}}