![Example of the stacking procedure for the Maidanak data obtained on 2025 August 15, based on ten 60 s exposures in each of the B, V , and R filters. Left: Comet-centered stack, showing the coma morphology without trailing of the comet signal. The pink circle indicates an aperture radius of 10 000 km. Right: Sidereal stack used for photometric calibration, in which the comet appears trailed.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/The-Inbound.png?resize=1200%2C720&ssl=1)
[astro-ph.EP] Interstellar objects (ISOs) provide direct constraints on the composition and evolution of extrasolar planetary systems. As the third confirmed ISO, comet 3I/ATLAS offers a rare opportunity to study pristine […]
Astrogeology
![Mechanisms that contribute to dust growth just beyond the snow line. Many-seed icy aggregates grow in the outer disk’s regions due to the high sticking efficiency of water ice and disintegrate as they cross the water snow line (green-to-blue interface) into silicate monomers and water vapor. Both diffuse back across the snow line due to turbulence, facilitating further accumulation of icy water and the growth of icy aggregates just behind the snow line, effects found in our numerical model as well (see Figs. 7 and E.2).-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Hydrodynamics.png?resize=1200%2C721&ssl=1)
Posted inAstrogeology
Hydrodynamics Modeling Of The Water Snow Line In Young Protoplanetary Disks With Dust-size-dependent Opacities
[astro-ph.EP] Aims. We investigated the properties of the water snow line during the early stages of disk evolution, paying particular attention to the effects of gravitational instability and dust growth […]
Posted inMars
Meteorite Helps Bridge The Data Gap In the Geologic History Of Mars
[Boston College] Scientists have determined a newly discovered meteorite from Mars is 1.27-billion years old and derived from a previously unsampled, pristine source on the Red Planet, the team reported […]
![(Top) Measured OC albedo values from Goldstone (from Table 4) and (bottom) measured OC albedo values from the GBT (from Table 5). The horizontal dashed lines indicate the weighted means of the albedos, which is 0.90 for Goldstone and 0.80 for GBT. The error bars on our albedo values are taken to be the total uncertainty calculated in Section 4. The color bar on the right shows the dates of our observations in YYMMDD. The x-axis is the subradar point west longitude. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Radar-observations.png?resize=1200%2C751&ssl=1)
Posted inEuropa
Radar Observations Of Europa in 2011-2024: New Insights Into Radar Scattering Properties
[astro-ph.EP] Three of Jupiter’s Galilean satellites – Europa, Ganymede, and Callisto – are of particular scientific interest due to their icy shells and suspected subsurface oceans. However, the radar properties […]
Posted inMars
A Mars Impact Crater Surrounded By Chunks Of Water Ice
[NASA] Boulder-size blocks of water ice can be seen around the rim of this giant meteoroid impact crater on Mars, as viewed by the High-Resolution Imaging Science Experiment (HiRISE camera) […]
Posted inAstrochemistry
Catalytic Formation of H2 On Carbonaceous Dust Grains – Implications For Interstellar Observations
[astro-ph.GA] We use kinetic Monte Carlo (KMC) simulations to study molecular hydrogen formation on carbonaceous dust grain surfaces, validated against recent laboratory measurements of H2 formation on coronene films at […]
Posted inEnceladus
The Enceladian Crater Production Function
[astro-ph.EP]. Interpreting Enceladus’s past and present surface history and interior state remains challenging, owing to uncertain prescription of its impact bombardment history and limited interpretation of its crater statistics. Further […]
![CI mass as a function of radial distance from the host star, for a continuum of solid surface densities. Over-plotted is the FI1 mass (𝑀¤ = 10−9 M⊙ yr−1 ) for a continuum of maximum Stokes numbers, as well as the MFI1 (opaque purple) and MFI2 (dashed red) masses and the PI mass (dotted black). The last three show no continuum of mass distributions, since we vary their initial mutual Hill spacing within the simulation. Thus, all initial simulations begin from the same mass distribution model, albeit with a different number of embryos at different spacings.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Effects-of-Pebble.png?resize=1200%2C715&ssl=1)
Posted inExoplanets, -moons, -comets
Effects Of Pebble Accretion Isolation Mass On Observable Exoplanet Properties
[astro-ph.EP] The Kepler Mission has discovered a plethora of planetary systems with super-Earth sized planets.
Posted inMars
Zhurong Mars Rover Observations Primary Evaporite In Southern Utopia Planitia
[Nature] The Zhurong rover has identified a layer consisting of platy rocks enriched in hydrous minerals on a ~0.76-Ga surface in southern Utopia Planitia, indicating unexpected recent aqueous activity on […]
Posted inMars
ExoMars Rosalind Franklin Rover Recon: Geological History Of Oxia Planum
[NASA] This crater contains exposures in the rim that can corroborate prevailing hypotheses for Oxia Planum’s geologic history ahead of the ExoMars Rosalind Franklin rover’s landing, currently planned for 2030. […]