Results 31 to 40 of about 193,103 (196)
Atmospheres of Rocky Exoplanets [PDF]
Annual Review of Astronomy and Astrophysics, 60, 1, 2022, 2021 Rocky planets are common around other stars, but their atmospheric properties remain largely unconstrained. Thanks to a wealth of recent planet discoveries and upcoming advances in observing capability, we are poised to characterize the atmospheres of dozens of rocky exoplanets in this decade.
arxiv +1 more source
The Possible Evolution of an Exoplanet’s Atmosphere
Eos, 2021 Scientific sleuths explore data gathered trillions of kilometers away and put forth different, and often conflicting, ideas to reconstruct the gaseous envelope on a distant rocky exoplanet, GJ 1132 b.
openaire +1 more source
Deuterium Escape on Photoevaporating Sub-Neptunes
The Astrophysical Journal Letters, 2023 We investigate the evolution of the deuterium-to-hydrogen (D/H) mass ratio driven by EUV photoevaporation of hydrogen-rich atmospheres of close-in sub-Neptunes around solar-type stars.
Pin-Gao Gu, Howard Chen
doaj +1 more source
Scaling K2. VII. Evidence For a High Occurrence Rate of Hot Sub-Neptunes at Intermediate Ages
The Astronomical Journal, 2023 The NASA K2 mission obtained high-precision time-series photometry for four young clusters, including the near-twin 600–800 Myr old Praesepe and Hyades clusters. Hot sub-Neptunes are highly prone to mass-loss mechanisms, given their proximity to the host
Jessie L. Christiansen +8 more
doaj +1 more source
Exoplanet secondary atmosphere loss and revival [PDF]
Proceedings of the National Academy of Sciences, 117, 18264-18271
(2020), 2020 The next step on the path toward another Earth is to find atmospheres similar to those of Earth and Venus - high-molecular-weight (secondary) atmospheres - on rocky exoplanets. Many rocky exoplanets are born with thick (> 10 kbar) H$_2$-dominated atmospheres but subsequently lose their H$_2$; this process has no known Solar System analog.
arxiv +1 more source
The Astronomical Journal, 2023 Irradiated Jovian atmospheres are complex and dynamic and can undergo temporal variations due to the close proximity of their parent stars. Of the Jovian planets that have been cataloged to date, KELT-9b is the hottest gas giant known, with an ...
Nataliea Lowson +12 more
doaj +1 more source
Water on Hot Rocky Exoplanets [PDF]
, 2021 Data suggest that most rocky exoplanets with orbital period $p$ $<$ 100 d ("hot" rocky exoplanets) formed as gas-rich sub-Neptunes that subsequently lost most of their envelopes, but whether these rocky exoplanets still have atmospheres is unknown. We identify a pathway by which 1-1.7 $R_{Earth}$ (1-10 $M_{Earth}$) rocky exoplanets with orbital periods
arxiv +1 more source
Spectral evolution of gaseous exoplanet atmospheres due to hydrodynamic escape
, 2023 The evolution of stars on grand time-scales affect their surroundings in many ways. Due to their intrinsic rotation, causing strong magnetic activity, they vary greatly in radiative activity in X-ray and ultraviolet (XUV) throughout their lifetime. Planets orbiting these stars close-in could, consequently, be affected by these drastic radiative changes.
Amy Louca, Yamila Miguel
openaire +1 more source
Outflowing Helium from a Mature Mini-Neptune
The Astrophysical Journal Letters, 2023 We announce the detection of escaping helium from TOI 2134b, a mini-Neptune a few gigayears old. The average in-transit absorption spectrum shows a peak of 0.37% ± 0.05% and an equivalent width of W _avg = 3.3 ± 0.3 mÅ.
Michael Zhang +4 more
doaj +1 more source
Nonthermal Atmospheric Escape on the Kepler-11 “Super-Earths” Driven by Stellar Wind Sputtering
The Astrophysical Journal, 2023 Jeans escape or hydrodynamic escape is believed to dominate atmospheric loss for hot Jupiters. However, nonthermal mechanisms likely contribute substantially on hydrogen-rich “super-Earths” with relatively cold and extended atmospheres.
Hao Gu +4 more
doaj +1 more source