Updated
Updated · spacedaily.com · Jul 25
MESSENGER Confirmed Mercury Polar Ice in 2012, Estimating Up to 1.4 Quadrillion Kilograms
Updated
Updated · spacedaily.com · Jul 25

MESSENGER Confirmed Mercury Polar Ice in 2012, Estimating Up to 1.4 Quadrillion Kilograms

1 articles · Updated · spacedaily.com · Jul 25

Summary

  • Three 2012 MESSENGER studies tied Mercury’s polar deposits to water ice, using neutron data, laser reflectance measurements and thermal models rather than direct sampling.
  • Hydrogen-rich signals from the north pole implied roughly 2.1 × 10^13 to 1.4 × 10^15 kilograms of water, while mapped radar-bright deposits lined up with permanently shadowed craters at both poles.
  • The coldest crater floors can stay below 100 kelvin, letting some ice remain exposed, while slightly warmer shadowed areas appear to hold buried ice beneath a dark insulating layer.
  • Not all cold traps contain radar-bright ice, suggesting differences in delivery, loss, burial depth or instrument resolution rather than shadow alone determining where deposits persist.
  • BepiColombo, due to enter Mercury orbit on Nov. 21, 2026, is expected to refine maps of polar ice, chemistry and temperatures, especially in the less-characterized south.

Insights

If Mercury may hold one of the Solar System’s biggest non-Earth ice stores, how much is exposed and what lies beneath the dark surface layer?
Did comets, asteroids, or Mercury itself create its polar ice—and could some deposits be surprisingly young?