permanently shadowed regions Archives - Astrobiology

Initial structure of the Impact Plume 60 s post impact. The impactor strikes from the left, at a 60° angle from horizontal, with the sun located to the right.There is a visible asymmetry in the plume due to the direction of impact; the “hole” on the right side of the plume is a bubble in this 2D slice of a fully 3D plume due to the removal of water vapor-rock mixtures from the simulation during the sampling from SOVA into DSMC codes (Prem et al. 2015). (Top) the plume contains a region of high density (~1022 molecules/m3 ) just above the point of impact, which rapidly drops toward the edges of the plume. (Bottom, left) The high plume densities correspond to short mean free paths for the vapor molecules. (Bottom, right) Comparing this mean free path with the length scale of the density gradient reveals very small Knudsen numbers throughout; the entire plume (except for the very outermost edges) is clearly within the continuum flow regime at this time, rather than the slip-flow, Knudsen, or Free Molecular regimes. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Comets and Asteroids, Cryobiology, Icy Worlds, Imaging & Spectroscopy, Impact events, Mapping, Geodesy, Cartography, Bathymetry, Mercury, Status Report

Transport of Water In A Transient, Impact-Generated Atmosphere On Mercury

by Keith CowingJune 5, 2026June 26, 2026

Mercury’s polar cold traps host water ice deposits that are likely populated with impact-delivered water via Mercury’s exosphere.

Lunar south pole areas of permanent shadow. NASA Video

Artemis & Lunar Exploration, Biophysics, Biosignatures & Paleobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Cryobiology, Extremeophiles and Extreme Environments, Genomics, Proteomics, Bioinformatics, Habitable Zones, Icy Worlds, Moon, Planetary Protection & Biosafety, Status Report

A Microbial Survival Model for the Permanently Shadowed Regions of the Moon Shows Long-Term Survival of Terrestrial Microbial Contamination

by Keith CowingJune 9, 2025June 9, 2025

Previous models of microbial survival on the moon do not directly consider the permanently shadowed regions (PSRs). These regions shield their interiors from many of the biocidal factors encountered in […]

This final prospectivity map synthesizes eight evidence layers: ISRs, maximum temperature, PSRs, slope, curvature, aspect, distance to PSRs, and density of PSRs. The color gradient signifies prospectivity levels, with cool tones indicating higher potential and warm tones suggesting lower potential. Specifically, dark blue areas are deemed highly prospective, light blue suggests favorable conditions, yellow denotes permissive regions, and red areas are considered nonprospective. -- The Planetary Science Journal

Artemis & Lunar Exploration, Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exploration Gear & Tech, Icy Worlds, Missions & Hardware, Moon, Robotics/Rovers/UAVs, Status Report, Water/Hycean Worlds & Oceanography

Astrochemistry: Prospectivity Modeling of the NASA VIPER Landing Site at Mons Mouton near the Lunar South Pole

by Keith CowingMay 7, 2025May 7, 2025

We use a high-resolution digital elevation model and a numerical thermal model to produce a variety of inputs for a water-ice prospectivity model for the Volatiles Investigating Polar Exploration Rover […]

A visualization of Shackleton crater. The near (Earth-facing) side of the Moon is to the right. Color coded and contoured elevation illuminates the crater floor. -- NASA

Artemis & Lunar Exploration, Biophysics, Biosignatures & Paleobiology, Extremeophiles and Extreme Environments, Habitable Zones, Microbiology & Virology, Moon, Panspermia, Planetary Protection & Biosafety, Status Report

A Microbial Survival Model For The permanently Shadowed Regions Of The Moon Shows Long-Term Survival of Terrestrial Microbe Forward Contamination

by Keith CowingApril 10, 2025April 10, 2025

Based on previous models of microbial survival there are regions in the solar system which have high preservation potential for terrestrial spore-forming microbes such as Bacillus subtilis.

Additional bright deposits in shadowed craters proposed by Platz et al. (2016) shown at the highest available resolution in clear filter LAMO images, with the FC image number indicated. Images are shown as unprojected 150 × 150 pixel-sized crops with the contrast enhanced in shadowed areas. (a), (b), and (c) deposit #4. (d) and (e) #5. (f) #7. (g) #8. (h) #9. (i) #10. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Ceres, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Missions & Hardware, Status Report, Water/Hycean Worlds & Oceanography

Spectral Properties Of Bright Deposits In Permanently Shadowed Craters On Ceres

by Keith CowingJuly 24, 2024July 24, 2024

Bright deposits in permanently shadowed craters on Ceres are thought to harbor water ice. However, the evidence for water ice presented thus far is indirect.