![Left: Average ocean fraction, calculated assuming a seawater freezing point of −1.8°𝐶 for Cases 1 and 3 and 0°𝐶 for Case 2. White shows the ice, and blue ocean. Middle: The mean near-surface air temperatures. Shown within the black contours are the regions where these vary between above and below freezing over the course of a single Earth year. Right: The mean surface temperatures. Also shown within the black contours are the regions where these vary between above and below freezing over the course of a single Earth year: these regions are narrower than the air ‘perifreezing zone’.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/09/Sea-Ice.png?resize=1200%2C720&ssl=1)
[astro-ph.EP] Water worlds with potential deep oceans are at the forefront of currently observable exoplanetary habitability.
Biochemistry & Organic Chemistry
Posted inBiosignatures & Paleobiology
Carbon and Sulfur Isotopes of Microfossils and Pyrites from Neoarchean Cherts: Microbial Diversity in an Ancient Deep-Marine Environment
[Astrobiology (Journal) via PubMed] The 2.52 Ga Gamohaan Formation in South Africa offers critical insights into microbial ecosystems that inhabited deep-marine environments during the late Archean.
Posted inAstrogeology
Trans-Neptunian Objects Remember Their Past
[NASA]. For the first time, scientists used the joint power of NASA’s Hubble and James Webb Space Telescopes to study some of the most far-flung bodies in our solar system, […]
Posted inExoplanets, -moons, -comets
Two Extremely Irradiated Volatile-rich Sub-Neptunes With Companions In The TOI-426 And TOI-1839 Systems: Insights Into Arrival And Survival Near The Lower Edge Of The Neptunian Desert
[astro-ph.EP] Using TESS photometry and 147 HARPS radial velocities, we confirm two extremely irradiated, volatile-rich sub-Neptunes near the lower edge of the Neptunian desert: TOI-426 b and TOI-1839 b, orbiting […]
Posted inMars
Stability Of Uracil In Different Sulphates Under Martian-like UV Irradiation
[Icarus] Mars is one of the most probable and accessible places where life could have evolved beyond Earth.
Posted inOrigin & Evolution of Life
The Emergence Of Life In The Light Of Evolution
[q-bio.PE] The origin of life is often framed primarily as a chemical problem, yet life s defining feature is evolution.
Posted inOrigin & Evolution of Life
ReactionAtlas: Ab Origine Exploration Of Chemical Reaction Networks With Machine Learning
[cs.LG] Mapping a chemical reaction network, the graph of minima and transition states (TS) and the elementary reactions connecting them, is the natural language of chemistry, from catalysis to combustion […]
Posted inTitan
Dragonfly Gets Wired Up While Titan Landing Area Is Named
[NASA]. Peeking into the clean room at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, it might be one of the first things you notice about NASA’s Dragonfly: […]
Posted inMoon
Potential Survivable Niches For Microbial Life On The Lunar South Pole
[astro-ph.EP]. Most lunar surface conditions are incredibly harsh for microbial survival. High ultraviolet radiation, temperatures, and energetic particle radiation limit survival over most unprotected lunar surfaces, particularly in equatorial regions […]
Posted inBiosignatures & Paleobiology
Proto-Biosignatures and Planetary Geochemical Metabolism: A Thermodynamic Screening Model of Prebiotic Geochemical Organization
[Life (Basel)] Astrobiological observations usually return atmospheric, mineralogical, molecular, isotopic, or textural states rather than organisms.