cold trap Archives

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.

Map of the north polar region of Ceres. The color areas are areas that are continuously shadowed over a Ceres year, and therefore very cold. The axis tilt (obliquity) of Ceres slowly changes over time and is currently 4 degrees, but ranged between 2 and 20 degrees over time. The color indicates the maximum obliquity at which a location is in shadow through an entire orbit. Credit: Erwan Mazarico/GSFC.

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Press Release

History Of Ceres’s Young Cold Traps

by Keith CowingApril 16, 2024April 16, 2024

Ceres, the largest asteroid in our Solar System, harbors a dark secret: Extremely young ice deposits in permanently shadowed craters near its poles. If that sounds vaguely familiar, it’s because […]

cold trap

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

History Of Ceres’s Young Cold Traps

Material Cycling Across Earth’s Spheres And Triggers Of Cambrian Explosion: A Tectonic Perspective

Where Does Earth’s Nitrogen Go? Two Atoms Offer A Clue

Exotic Methanol Discovered In Planet-Building Zones

More Than One Thousand TESS Planets

First Detection Of Variable Water Clouds Outside Of Our Solar System