Transit detection of the long-period volatile-rich super-Earth ν2 Lupi d with CHEOPS
Date
28/06/2021Author
Funder
Grant ID
ST/R00824/1
ST/R003203/1
ST/M001296/1
Metadata
Show full item recordAbstract
Exoplanets transiting bright nearby stars are key objects for advancing our knowledge of planetary formation and evolution. The wealth of photons from the host star gives detailed access to the atmospheric, interior and orbital properties of the planetary companions. ν2 Lupi (HD 136352) is a naked-eye (V = 5.78) Sun-like star that was discovered to host three low-mass planets with orbital periods of 11.6, 27.6 and 107.6 d via radial-velocity monitoring1. The two inner planets (b and c) were recently found to transit2, prompting a photometric follow-up by the brand new Characterising Exoplanets Satellite (CHEOPS). Here, we report that the outer planet d is also transiting, and measure its radius and mass to be 2.56 ± 0.09 R⊕ and 8.82 ± 0.94 M⊕, respectively. With its bright Sun-like star, long period and mild irradiation (~5.7 times the irradiation of Earth), ν2 Lupi d unlocks a completely new region in the parameter space of exoplanets amenable to detailed characterization. We refine the properties of all three planets: planet b probably has a rocky mostly dry composition, while planets c and d seem to have retained small hydrogen–helium envelopes and a possibly large water fraction. This diversity of planetary compositions makes the ν2 Lupi system an excellent laboratory for testing formation and evolution models of low-mass planets.
Citation
Delrez , L , Ehrenreich , D , Alibert , Y , Bonfanti , A , Borsato , L , Fossati , L , Hooton , M J , Hoyer , S , Pozuelos , F J , Salmon , S , Sulis , S , Wilson , T G , Adibekyan , V , Bourrier , V , Brandeker , A , Charnoz , S , Deline , A , Guterman , P , Haldemann , J , Hara , N , Oshagh , M , Sousa , S G , Van Grootel , V , Alonso , R , Anglada-Escudé , G , Bárczy , T , Barrado , D , Barros , S C C , Baumjohann , W , Beck , M , Bekkelien , A , Benz , W , Billot , N , Bonfils , X , Broeg , C , Cabrera , J , Collier Cameron , A , Davies , M B , Deleuil , M , Delisle , J-B , Demangeon , O D S , Demory , B-O , Erikson , A , Fortier , A , Fridlund , M , Futyan , D , Gandolfi , D , Garcia Muñoz , A , Gillon , M , Guedel , M , Heng , K , Kiss , L , Laskar , J , Lecavelier des Etangs , A , Lendl , M , Lovis , C , Maxted , P F L , Nascimbeni , V , Olofsson , G , Osborn , H P , Pagano , I , Pallé , E , Piotto , G , Pollacco , D , Queloz , D , Rauer , H , Ragazzoni , R , Ribas , I , Santos , N C , Scandariato , G , Ségransan , D , Simon , A E , Smith , A M S , Steller , M , Szabó , G M , Thomas , N , Udry , S & Walton , N A 2021 , ' Transit detection of the long-period volatile-rich super-Earth ν 2 Lupi d with CHEOPS ' , Nature Astronomy , vol. 5 , pp. 775-787 . https://doi.org/10.1038/s41550-021-01381-5
Publication
Nature Astronomy
Status
Peer reviewed
ISSN
2397-3366Type
Journal item
Description
A.C.C. and T.G.W. acknowledge support from STFC consolidated grant ST/M001296/1.Collections
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