WASP-80 is a K-type main-sequence star about 162 light-years away from Earth. The star's age is much younger than the Sun's at 1.352±0.222 billion years.[9] WASP-80 could be similar to the Sun in concentration of heavy elements, although this measurement is highly uncertain.[8]
The star was named Petra in 2019 by Jordanian amateur astronomers as part of the NameExoWorlds contest.[11]
Three multiplicity surveys in 2015-2018 did not detect any stellar companions to WASP-80, but a survey in 2020 detected a 0.07M☉ companion candidate at an angular separation 2.132±0.010 arcseconds, with a false alarm probability of 3%.[12]
Planetary system
In 2013 a transitinghot Jupiter planet WASP-80 b was detected on a tight, circular orbit.[3] The planet was named Wadirum by Jordanian astronomers in December 2019.[11] Its equilibrium temperature is 825±19 K, while measured temperature of the dayside is 937±48 K and temperature of the nightside is 851±14 K. This temperature difference indicates a rather low planetary albedo and weak global transport of heat.[13]
Measurement of the Rossiter–McLaughlin effect in 2015 revealed WASP-80b's is orbit is well-aligned with the equatorial plane of the star, with orbital obliquity equal to 14±14°.[5]
Although one transmission spectrum of the planetary atmosphere showed signs of ionised potassium,[14] another measurement in 2017 yielded a gray and featureless spectrum, probably due to a high cloud deck[15] or haze[16] in the atmosphere of WASP-80b. [13] Evidence for water vapour and methane molecules (CH4) were found for the planet through observations of JWST.[17] This discovery helped uncovers the origin and evolution of the planet.[17]
^ abcTriaud, A. H. M. J.; Anderson, D. R.; Collier Cameron, A.; Doyle, A. P.; Fumel, A.; Gillon, M.; Hellier, C.; Jehin, E.; Lendl, M.; Lovis, C.; Maxted, P. F. L.; Pepe, F.; Pollacco, D.; Queloz, D.; Ségransan, D.; Smalley, B.; Smith, A. M. S.; Udry, S.; West, R. G.; Wheatley, P. J. (2013). "WASP-80b: A gas giant transiting a cool dwarf". Astronomy & Astrophysics. 551: A80. arXiv:1303.0254. Bibcode:2013A&A...551A..80T. doi:10.1051/0004-6361/201220900. S2CID67805044.
^ abcdefTriaud, A. H. M. J.; Gillon, M.; Ehrenreich, D.; Herrero, E.; Lendl, M.; Anderson, D. R.; Collier Cameron, A.; Delrez, L.; Demory, B.-O.; Hellier, C.; Heng, K.; Jehin, E.; Maxted, P. F. L.; Pollacco, D.; Queloz, D.; Ribas, I.; Smalley, B.; Smith, A. M. S.; Udry, S. (2015). "WASP-80b has a dayside within the T-dwarf range". Monthly Notices of the Royal Astronomical Society. 450 (3): 2279–2290. arXiv:1503.08152. doi:10.1093/mnras/stv706.
