![SpeX SXD spectrum of TOI-6981. The target spectrum (red) is shown alongside that of the M3.5V standard Luyten’s Star (grey), offset vertically for clarity. Regions of strong telluric absorption are shaded, and strong M-dwarf spectral features are indicated. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/TOI-6981.png?resize=1200%2C718&ssl=1)
[astro-ph.EP] We present TOI-6981 b, a cold (Teq= 170.0 +/-4.5 K, assuming an Earth-like albedo) sub-Neptune (Rb=2.40+/-0.10 R⊕) on a 60.8 day orbit around around its M4-type host star (R*=0.304 […]
water ice line
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report
Diversity In The Haziness And Chemistry Of Temperate Sub-Neptunes
Recent transit observations of K2-18b and TOI-270d revealed strong molecular absorption signatures, lending credence to the idea that temperate sub-Neptunes (Teq=250-400K) have upper atmospheres mostly free of aerosols.
Posted inAstrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gas Giants, Icy Worlds, Imaging & Spectroscopy, Status Report
Recipes For Forming A Carbon-rich Giant Planet
The exploration of carbon-to-oxygen ratios has yielded intriguing insights into the composition of close-in giant exoplanets, giving rise to a distinct classification: carbon-rich planets, characterized by a carbon-to-oxygen ratio ≥ […]
Posted inAstrochemistry, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Status Report, Water/Hycean Worlds & Oceanography
Exoplanet Volatile Carbon Content as a Natural Pathway for Haze Formation
We explore terrestrial planet formation with a focus on the supply of solid-state organics as the main source of volatile carbon.