WASP-121b

Last updated

WASP-121b / Tylos
WASP-121b 01.jpg
Artist's impression of WASP-121b and its host star
Discovery [1]
Discovered by L. Delrez et al.
Discovery date2015
Transit
Designations
Tylos [2]
Orbital characteristics [3]
0.02596+0.00043
−0.00063  AU
Eccentricity <0.0032
1.27492504(15)  d
Inclination 88.49°±0.16°
10°±10°
Star WASP-121
Physical characteristics [3]
Mean radius
1.753±0.036  RJ
Mass 1.157±0.070  MJ
Mean density
0.266+0.024
−0.022  g/cm3
9.33+0.71
−0.67  m/s2 (0.95 g)
Temperature 2602±53  K (2,329 °C; 4,224 °F) [4]

    WASP-121b, formally named Tylos, [2] is an exoplanet orbiting the star WASP-121. [5] [6] WASP-121b is the first exoplanet found to contain water in an extrasolar planetary stratosphere (i.e., an atmospheric layer in which temperatures increase as the altitude increases). [5] [6] WASP-121b is in the constellation Puppis, [7] and is about 858 light-years from Earth. [8] [5] [9]

    Contents

    Nomenclature

    In August 2022, this planet and its host star were included among 20 systems to be named by the third NameExoWorlds project. [10] The approved names, proposed by a team from Bahrain, were announced in June 2023. WASP-121b is named Tylos after the ancient Greek name for Bahrain, and its host star is named Dilmun after the ancient civilization. [2]

    Characteristics

    WASP-121b - computer simulated views (August 2018) PIA22565-Exoplanet-WASP121b-ComputerSimViews-20180809.jpg
    WASP-121b - computer simulated views (August 2018)

    WASP-121b is a hot Jupiter exoplanet with a mass about 1.16 times that of Jupiter and a radius about 1.75 times that of Jupiter. The exoplanet orbits WASP-121, its host star, every 1.27 days. [3]

    In 2019 a work by Hellard et al. discussed the possibility of measuring the Love number of transiting hot Jupiters using HST/STIS. A tentative measurement of for WASP-121b was published in the same work. [11] [12]

    The planetary orbit is inclined to the equatorial plane of the star by 8.1°. [13]

    Atmospheric composition

    A spectral survey in 2015 attributed 2,500 °C (4,530 °F), hot [5] stratosphere absorption bands to water molecules, titanium(II) oxide (TiO) and vanadium(II) oxide (VO). [14] Neutral iron was also detected in the stratosphere of WASP-121b in 2020, [15] [16] along with neutral chromium and vanadium. [17] The detection claims of titanium(II) oxide (TiO) and vanadium(II) oxide (VO) have since been disproved. [6] [18] [19] [20]

    Reanalysis of aggregated spectral data was published in June 2020. Neutral magnesium, calcium, vanadium, chromium, iron, and nickel, along with ionized sodium atoms, were detected. The low quality of available data preclude a positive identification of any molecular species, including water. The atmosphere appears to be significantly out of chemical equilibrium and possibly escaping. [21] The strong atmospheric flows beyond the Roche lobe, indicating ongoing atmosphere loss, were confirmed in late 2020. [13]

    In 2021, the planetary atmosphere turned out to be slightly more blue and less absorbing, which may be an indication of planetary weather patterns. [22] By mid-2021, the presence of ions of iron, chromium, vanadium and calcium in the planetary atmosphere was confirmed. [23] In 2022, barium was also detected. [24] By 2022, an absence of titanium in the planetary atmosphere was confirmed and attributed to the nightside condensation of highly refractory titanium dioxide. [25]

    Observations by the Hubble Space Telescope from 2016-2019, published in 2024, confirm variability in the atmosphere of WASP-121b. [26] [27]

    Possible exomoon

    The sodium detected via absorption spectroscopy around WASP-121b [21] is consistent with an extrasolar gas torus, possibly fueled by a hidden exo-Io. [28]

    See also

    Related Research Articles

    <span class="mw-page-title-main">Hot Jupiter</span> Class of high mass planets orbiting close to a star

    Hot Jupiters are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital periods. The close proximity to their stars and high surface-atmosphere temperatures resulted in their informal name "hot Jupiters".

    <span class="mw-page-title-main">HD 189733 b</span> Hot Jupiter exoplanet in the constellation Vulpecula

    HD 189733 b is an exoplanet in the constellation of Vulpecula approximately 64.5 light-years away from our Solar System. Astronomers in France discovered the planet orbiting the star HD 189733 on October 5, 2005, by observing its transit across the star's face. With a mass 11.2% higher than that of Jupiter and a radius 11.4% greater, HD 189733 b orbits its host star once every 2.2 days at an orbital speed of 152.0 kilometers per second, making it a hot Jupiter with poor prospects for extraterrestrial life.

    <span class="mw-page-title-main">WASP-6b</span> Extrasolar planet

    WASP-6b, also named Boinayel, is an exoplanet approximately 650 light years away in the constellation Aquarius. It was discovered in 2008, by the WASP survey, by astronomical transit across its parent star WASP-6. This planet orbits at only 4% of the Earth-Sun distance. The planet has a mass half that of Jupiter, but its insolation has forced a thermal expansion of its radius to greater than that of Jupiter. Thus, this planet is an inflated hot Jupiter. Starspots on the host star WASP-6 helped to refine the measurements of the mass and the radius of the planet.

    <span class="mw-page-title-main">WASP-17b</span> Hot-Jupiter exoplanet in the orbit of the star WASP-17

    WASP-17b is an exoplanet in the constellation Scorpius that is orbiting the star WASP-17. Its discovery was announced on 11 August 2009. It is the first planet discovered to have a retrograde orbit, meaning it orbits in a direction counter to the rotation of its host star. This discovery challenged traditional planetary formation theory. In terms of diameter, WASP-17b is one of the largest exoplanets discovered and at half Jupiter's mass, this made it the most puffy planet known in 2010. On 3 December 2013, scientists working with the Hubble Space Telescope reported detecting water in the exoplanet's atmosphere.

    WASP-33b is an extrasolar planet orbiting the star HD 15082. It was the first planet discovered to orbit a Delta Scuti variable star. With a semimajor axis of 0.026 AU and a mass likely greater than Jupiter's, it belongs to the hot Jupiter class of planets.

    <span class="mw-page-title-main">WASP-43b</span> Extrasolar planet in the constellation Sextans

    WASP-43b, formally named Astrolábos, is a transiting planet in orbit around the young, active, and low-mass star WASP-43 in the constellation Sextans. The planet is a hot Jupiter with a mass twice that of Jupiter, but with a roughly equal radius. WASP-43b was flagged as a candidate by the SuperWASP program, before they conducted follow-ups using instruments at La Silla Observatory in Chile, which confirmed its existence and provided orbital and physical characteristics. The planet's discovery was published on April 14, 2011.

    WASP-121, also known as CD-38 3220, is a magnitude 10.4 star located approximately 858 light-years away in the constellation Puppis. WASP-121 has a mass and radius similar to the Sun's. It hosts one known exoplanet.

    <span class="mw-page-title-main">WASP-31b</span> Hot Jupiter orbiting the star WASP-31

    WASP-31b is a low-density (puffy) "hot Jupiter" extrasolar planet orbiting the metal-poor dwarf star WASP-31. The exoplanet was discovered in 2010 by the WASP project. WASP-31b is in the constellation of Crater, and is about 1305 light-years from Earth.

    WASP-79b, also known as Pollera, is an extrasolar planet orbiting the star CD-30 1812. This planet is in the constellation Eridanus, and is about 810 light-years from Earth.

    <span class="mw-page-title-main">WASP-76b</span> Hot Jupiter orbiting WASP-76

    WASP-76b is an exoplanet classified as a Hot Jupiter. It is located in the constellation Pisces and orbits its host star, WASP-76, at a distance of approximately 0.033 astronomical units (AU). The orbital period of WASP-76b is approximately 1.8 days. Its mass is about 0.92 times that of Jupiter. The discovery of WASP-76b took place on October 21, 2013, and it is currently the only known planet in the WASP-76 system as of 2022. The equilibrium temperature of WASP-76b is estimated to be around 2,190 K, However, the measured daytime temperature is higher, reaching approximately 2,500 ± 200 K.

    WASP-52 is a K-type main-sequence star about 570 light-years away. It is older than the Sun at 10.7+1.9
    −4.5     billion years, but it has a similar fraction of heavy elements. The star has prominent starspot activity, with 3% to 14% of the stellar surface covered by areas 575±150 K cooler than the rest of the photosphere.

    WASP-75 is a F-type main-sequence star about 980 light-years away. The star is much younger than the Sun at approximately 2.9±0.2 billion years. WASP-75 is similar to the Sun in its concentration of heavy elements.

    WASP-88 is a F-type main-sequence star. Its surface temperature is 6450±61 K. WASP-88 is similar to the Sun in its concentration of heavy elements, with a metallicity Fe/H index of 0.03±0.04, and is younger at an age of 3.0±1.3 billion years.

    WASP-80 is a K-type main-sequence star about 162 light-years away. The star's age is much younger than the Sun's at 1.352±0.222 billion years. WASP-80 is similar to the Sun in concentration of heavy elements, although this measurement is highly uncertain.

    WASP-103 is an F-type main-sequence star located 1,800 ± 100 light-years away in the constellation Hercules. Its surface temperature is 6,110±160 kelvins (K). The star's concentration of heavy elements is similar to that of the Sun. WASP-103 is slightly younger than the Sun at 4±1 billion years. The chromospheric activity of the star is elevated due to interaction with the giant planet on a close-in orbit.

    <span class="mw-page-title-main">WASP-96b</span> Gas giant exoplanet targeted for spectroscopy

    WASP-96b is a gas giant exoplanet. Its mass is 0.48 times that of Jupiter. It is 0.0453 AU from the class G star WASP-96, which it orbits every 3.4 days. It is about 1,140 light-years away from Earth, in the constellation Phoenix. It was discovered in 2013 by the Wide Angle Search for Planets (WASP).

    References

    1. ↑ Delrez, L.; Santerne, A.; Almenara, J.-M.; Anderson, D. R.; Collier-Cameron, A.; Díaz, R. F.; Gillon, M.; Hellier, C.; Jehin, E.; Lendl, M.; Maxted, P. F. L.; Neveu-Vanmalle, M.; Pepe, F.; Pollacco, D.; Queloz, D.; Ségransan, D.; Smalley, B.; Smith, A. M. S.; Triaud, A. H. M. J.; Udry, S.; Van Grootel, V.; West, R. G. (2015), "WASP-121 b: A hot Jupiter close to tidal disruption transiting an active F star", Monthly Notices of the Royal Astronomical Society, 458 (4): 4025–4043, arXiv: 1506.02471 , Bibcode:2016MNRAS.458.4025D, doi:10.1093/mnras/stw522
    2. 1 2 3 "2022 Approved Names". nameexoworlds.iau.org. IAU . Retrieved 7 June 2023.
    3. 1 2 3 Bourrier, V.; Ehrenreich, D.; et al. (March 2020). "Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS). III. Atmospheric structure of the misaligned ultra-hot Jupiter WASP-121b". Astronomy & Astrophysics . 635: A205. arXiv: 2001.06836 . Bibcode:2020A&A...635A.205B. doi:10.1051/0004-6361/201936640.
    4. ↑ Changeat, Q.; Edwards, B.; et al. (May 2022). "Five Key Exoplanet Questions Answered via the Analysis of 25 Hot-Jupiter Atmospheres in Eclipse". The Astrophysical Journal Supplement Series . 260 (1): 3. arXiv: 2204.11729 . Bibcode:2022ApJS..260....3C. doi: 10.3847/1538-4365/ac5cc2 .
    5. 1 2 3 4 Landau, Elizabeth; Villard, Ray (2 August 2017). "Hubble Detects Exoplanet with Glowing Water Atmosphere". NASA . Retrieved 2 August 2017.
    6. 1 2 3 Evans, Thomas M.; Sing, David K.; et al. (2 August 2017). "An ultrahot gas-giant exoplanet with a stratosphere". Nature . 548 (7665): 58–61. arXiv: 1708.01076 . Bibcode:2017Natur.548...58E. doi:10.1038/nature23266. ISSN   1476-4687. PMID   28770846. S2CID   205258293.
    7. ↑ Staff. "Finding the constellation which contains given sky coordinates". djm.cc. Retrieved 3 August 2017.
    8. ↑ Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211 . Bibcode:2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940 . S2CID   244398875. Gaia DR3 record for this source at VizieR.
    9. ↑ Greicius, Tony (7 August 2018). "Water Is Destroyed, Then Reborn in Ultrahot Jupiters". NASA. Retrieved 15 November 2018.
    10. ↑ "List of ExoWorlds 2022". nameexoworlds.iau.org. IAU. 8 August 2022. Retrieved 27 August 2022.
    11. ↑ Hellard, Hugo; Csizmadia, Szilárd; Padovan, Sebastiano; Sohl, Frank; Rauer, Heike (2020). "HST/STIS capability for Love number measurement of WASP-121b". The Astrophysical Journal. 889 (1): 66. arXiv: 1912.05889 . Bibcode:2020ApJ...889...66H. doi: 10.3847/1538-4357/ab616e . S2CID   209324250.
    12. ↑ waspplanets (19 December 2019). "The tidal shape of the exoplanet WASP-121b". WASP Planets. Retrieved 20 January 2020.
    13. 1 2 Borsa, F.; et al. (2021), "Atmospheric Rossiter–Mc Laughlin effect and transmission spectroscopy of WASP-121b with ESPRESSO", Astronomy & Astrophysics, 645: A24, arXiv: 2011.01245 , Bibcode:2021A&A...645A..24B, doi:10.1051/0004-6361/202039344, S2CID   226237425
    14. ↑ Staff (2015). "Planet WASP-121 b". Extrasolar Planets Encyclopaedia . Retrieved 3 August 2017.
    15. ↑ Gibson, Neale P.; Merritt, Stephanie; Nugroho, Stevanus K.; Cubillos, Patricio E.; de Mooij, Ernst J. W.; Mikal-Evans, Thomas; Fossati, Luca; Lothringer, Joshua; Nikolov, Nikolay; Sing, David K.; Spake, Jessica J.; Watson, Chris A.; Wilson, Jamie (2020). "Detection of Fe I in the atmosphere of the ultra-hot Jupiter WASP-121b, and a new likelihood-based approach for Doppler-resolved spectroscopy". Monthly Notices of the Royal Astronomical Society. 493 (2): 2215. arXiv: 2001.06430 . Bibcode:2020MNRAS.493.2215G. doi:10.1093/mnras/staa228. S2CID   210714233.
    16. ↑ Cabot, Samuel H. C.; Madhusudhan, Nikku; Welbanks, Luis; Piette, Anjali; Gandhi, Siddharth (2020). "Detection of neutral atomic species in the ultra-hot jupiter WASP-121b". Monthly Notices of the Royal Astronomical Society. 494 (1): 363–377. arXiv: 2001.07196 . Bibcode:2020MNRAS.494..363C. doi:10.1093/mnras/staa748. S2CID   210838889.
    17. ↑ Ben-Yami, Maya; Madhusudhan, Nikku; Cabot, Samuel H. C.; Constantinou, Savvas; Piette, Anjali; Gandhi, Siddharth; Welbanks, Luis (2020). "Neutral Cr and V in the Atmosphere of Ultra-hot Jupiter WASP-121 B". The Astrophysical Journal. 897 (1): L5. arXiv: 2006.05995 . Bibcode:2020ApJ...897L...5B. doi: 10.3847/2041-8213/ab94aa . S2CID   219573825.
    18. ↑ Mikal-Evans, Thomas (27 June 2019). "An emission spectrum for WASP-121b measured across the 0.8–1.1 μm wavelength range using the Hubble Space Telescope". Monthly Notices of the Royal Astronomical Society. 488 (2): 2222–2234. arXiv: 1906.06326 . Bibcode:2019MNRAS.488.2222M. doi:10.1093/mnras/stz1753. hdl: 10150/634587 – via OUP.
    19. ↑ Merritt, S. R.; Gibson, N. P.; Nugroho, S. K.; Mooij, E. J. W. de; Hooton, M. J.; Matthews, S. M.; McKemmish, L. K.; Mikal-Evans, T.; Nikolov, N.; Sing, D. K.; Spake, J. J. (1 April 2020). "Non-detection of TiO and VO in the atmosphere of WASP-121b using high-resolution spectroscopy". Astronomy & Astrophysics. 636: A117. arXiv: 2002.02795 . Bibcode:2020A&A...636A.117M. doi: 10.1051/0004-6361/201937409 . ISSN   0004-6361.
    20. ↑ Mikal-Evans, Thomas; Sing, David K.; Kataria, Tiffany; Wakeford, Hannah R.; Mayne, Nathan J.; Lewis, Nikole K.; Barstow, Joanna K.; Spake, Jessica J. (2020). "Confirmation of water emission in the dayside spectrum of the ultrahot Jupiter WASP-121b". Monthly Notices of the Royal Astronomical Society. 496 (2): 1638–1644. arXiv: 2005.09631 . Bibcode:2020MNRAS.496.1638M. doi:10.1093/mnras/staa1628. S2CID   218684532.
    21. 1 2 Hoeijmakers, H.J.; Seidel, J.V.; Pino, L.; Kitzmann, D.; Sindel, J.P.; Ehrenreich, D.; Oza, A.V.; Bourrier, V.; Allart, R.; Gebek, A.; Lovis, C.; Yurchenko, S.N.; Astudillo-Defru, N.; Bayliss, D.; Cegla, H.; Lavie, B.; Lendl, M.; Melo, C.; Murgas, F.; Nascimbeni, V.; Pepe, F.; Segransan, D.; Udry, S.; Wyttenbach, A.; Heng, K. (18 September 2020). "Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) - IV. A spectral inventory of atoms and molecules in the high-resolution transmission spectrum of WASP-121 b". Astronomy & Astrophysics. 641: A123. arXiv: 2006.11308 . Bibcode:2020A&A...641A.123H. doi:10.1051/0004-6361/202038365. S2CID   219966241.
    22. ↑ Wilson, Jamie; Gibson, Neale P.; Lothringer, Joshua D.; Sing, David K.; Mikal-Evans, Thomas; De Mooij, Ernst J W.; Nikolov, Nikolay; Watson, Chris A. (2021), "Gemini/GMOS optical transmission spectroscopy of WASP-121b: Signs of variability in an ultra-hot Jupiter?", Monthly Notices of the Royal Astronomical Society, 503 (4): 4787–4801, arXiv: 2103.05698 , doi:10.1093/mnras/stab797
    23. ↑ Merritt, Stephanie R.; Gibson, Neale P.; Nugroho, Stevanus K.; De Mooij, Ernst J W.; Hooton, Matthew J.; Lothringer, Joshua D.; Matthews, Shannon M.; Mikal-Evans, Thomas; Nikolov, Nikolay; Sing, David K.; Watson, Chris A. (2021), "An inventory of atomic species in the atmosphere of WASP-121b using UVES high-resolution spectroscopy", Monthly Notices of the Royal Astronomical Society, 506 (3): 3853–3871, arXiv: 2106.15394 , doi:10.1093/mnras/stab1878
    24. ↑ Azevedo Silva, T.; et al. (2022), "Detection of barium in the atmospheres of the ultra-hot gas giants WASP-76b and WASP-121b", Astronomy & Astrophysics, 666: L10, arXiv: 2210.06892 , doi:10.1051/0004-6361/202244489, S2CID   252873126
    25. ↑ Hoeijmakers, H. J.; Kitzmann, D.; Morris, B. M.; Prinoth, B.; Borsato, N.; Pino, L.; Lee, E. K. H.; Akın, C.; Heng, K. (2022), The Mantis Network III: A titanium cold-trap on the ultra-hot Jupiter WASP-121 b., arXiv: 2210.12847
    26. ↑ "Hubble observes a changing exoplanet atmosphere". esahubble.org. ESA. 4 January 2024. Retrieved 4 January 2024.
    27. ↑ Changeat, Quentin; Skinner, Jack W.; et al. (January 2024). "Is the atmosphere of the ultra-hot Jupiter WASP-121b variable?". The Astrophysical Journal Supplement Series . arXiv: 2401.01465 .
    28. ↑ Gebek, Andrea; Oza, Apurva (29 July 2020). "Alkaline exospheres of exoplanet systems: evaporative transmission spectra". Monthly Notices of the Royal Astronomical Society. 497 (4): 5271–5291. arXiv: 2005.02536 . Bibcode:2020MNRAS.497.5271G. doi:10.1093/mnras/staa2193. S2CID   218516741 . Retrieved 8 December 2020.
    This page is based on this Wikipedia article
    Text is available under the CC BY-SA 4.0 license; additional terms may apply.
    Images, videos and audio are available under their respective licenses.