CO, H<sub>2</sub>O, and CH<sub>4 </sub>in the dusty atmosphere of a ≲ 5 Myr-old exoplanet

Autor(en)
Eric Gaidos, Teruyuki Hirano
Abstrakt

Very young massive planets are sufficiently luminous by their internal heat of formation to permit detailed studies, including spectroscopy of their atmospheres with large telescopes at sufficient resolution (λ/Δλ 1000) to identify major constituents to inform models of planet formation and early evolution. We obtained 1-2.4 μm (YJHK) spectra of the planetary-mass 'b' companion of 2MASS J04372171+2651014, a 1-3 Myr-old M dwarf member of the Taurus star-forming region, and one of the youngest such objects discovered to date. These indicate the presence of CO and possibly H2O and CH4 in the atmosphere, all suggesting a Teff of around 1200 K, characteristic of a L-T transition spectral type and consistent with previous estimates based on its luminosity and age. The absence or attenuation of spectral features at shorter wavelengths suggests the presence of micron-size dust, consistent with the object's red colour. The spectrum of 2M0437b resembles those of the HR 8799 planets, especially the innermost 'b' planet, with the exception of a pronounced flux deficit in the H-band of uncertain origin.

Organisation(en)
Institut für Astrophysik
Externe Organisation(en)
University of Hawaii at Manoa, National Institutes of Natural Sciences (NINS) , National Astronomical Observatory of Japan
Journal
Monthly Notices of the Royal Astronomical Society
Band
525
Seiten
6303-6311
Anzahl der Seiten
9
ISSN
0035-8711
DOI
https://doi.org/10.1093/mnras/stad2664
Publikationsdatum
11-2023
Peer-reviewed
Ja
ÖFOS 2012
103003 Astronomie, 103004 Astrophysik
Schlagwörter
ASJC Scopus Sachgebiete
Astronomy and Astrophysics, Space and Planetary Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/db77c955-ac0c-4be6-b2c7-062fe4fbc8a0