![Latitude-longitude maps of mean water vapour and hydrogen chloride volume mixing ratios and coefficient of variation (standard deviation divided by the mean) in percentage form at 20.91 km altitude. The values are calculated over four Venus solar days (468 Earth days). --[astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/How-long.png?resize=1200%2C717&ssl=1)
[astro-ph.EP] Resolving the ambiguity surrounding current Venusian volcanism is a primary objective for upcoming missions like EnVision and VERITAS.
Astrogeology
Posted inExoplanets, -moons, -comets
“Mega-Earths” Are Likely An Artifact Of Stellar Activity
[astro-ph.EP]. Empirical relations and planet formation simulations suggest an upper mass limit for rocky planets of ∼10M⊕, as cores above this will almost certainly undergo runaway gas accretion.
![A heterotrophic ecosystem enabled by fermentation on Enceladus. [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Fermentation.png?resize=1200%2C720&ssl=1)
Posted inEnceladus
Fermentation Heterotrophy Can Reproduce Enceladus’s H2 And CH4 Under Limited Serpentinization
[astro-ph.EP] Saturn’s icy moon Enceladus is a prime target in the search for life beyond Earth. Abundant H2 and CH4 in Enceladus’s south-polar plume have been shown to be consistent […]
![(Top row:) Composite images on three dates (Table 1) shown with a common display range from -0.01 to 0.02 adu pixel−1 . (Bottom row:) Same images from the top row contoured from 0.0004 adu pixel−1 in steps of 0.002 adu pixel−1 . Contours are smoothed over 8×8 pixel boxes. Yellow arrows show the projected antisolar direction while white arrows show the projected negative heliocentric velocity vector, from Table 1. The two directions are overlapping in the 2023 data. A 1′′ scale is common to all panels.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Hubble-Space-.png?resize=1200%2C725&ssl=1)
Posted inComets and Asteroids
Hubble Space Telescope Observations of Active Asteroid (101955) Bennu
[astro-ph.EP] Measurements from NASA’s OSIRIS-REx spacecraft revealed (101955) Bennu as a member of the active asteroid class.
Posted inBiogeochemical Cycles & Geobiology
Material Cycling Across Earth’s Spheres And Triggers Of Cambrian Explosion: A Tectonic Perspective
[ELSP] A comprehensive model of the Cambrian explosion featuring “multi-factors coupling and multi-sphere driving”. Supercontinent breakup and mantle plume activity served as the initial trigger of environmental change in the […]
Posted inAstrogeology
A JWST Study Oof Stardust. II. Polycyclic Aromatic Hydrocarbons in Comet 81P/Wild 2 And Implications For Primitive Solar System Carbon
[astro-ph.EP] We report observations of comet 81P/Wild 2, target of the Stardust sample return mission, on UT 2023 March 20 and 24 at a heliocentric distance (rH) of 1.85 au […]
Posted inEnceladus
Paleo-heat Flux Estimates Across Enceladus Derived From Flexural Response Of The Ice Shell
[Icarus] Saturn’s moon Enceladus has active plumes suggestive of locally high heat fluxes at present, and the present-day heating is reasonably well characterized. However, the moon’s thermal history is not […]
Posted inMars
A Journey To The Depths Of Ancient Mars?
[NASA/Alex Jones] After spending the last six months exploring “Lac de Charmes,” a region of ancient rock beyond Jezero crater’s western rim, Perseverance has stumbled upon a vast field of […]
Posted inMars
Curiosity Rover Catches A Stunning Martian Dawn
[NASA] A newly released panorama captured by NASA’s Curiosity rover offers the most detailed view yet of distant, wind-carved Martian cliffs, highlighting features the mission’s scientists have long been waiting […]
![Initial 𝑎c–𝑒c distribution of the 32,000 comets used in each end-to-end calculation. Dashed lines mark the semimajor axes of P7 and P8. The circular and eccentric planet calculations use identical comet initial states.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Planetary.png?resize=1200%2C604&ssl=1)
Posted inComets and Asteroids
Planetary Eccentricity Enhances Inward Comet Transport But Suppresses Gentle Impacts
[astro-ph.EP] Comets can supply volatile and prebiotic material to rocky planets, but survival of fragile molecules depends on atmospheric entry and impact. Compact planet chains can transfer comets inward at […]