Brown University | 2017 Sep 19
A Brown University study identifies three large surface ice deposits near Mercury’s north pole, and suggests there could be many additional small-scale deposits that would dramatically increase the planet’s surface ice inventory.
[img3="Brown researchers have found new evidence of ice sheets in permanently shadowed craters near the north pole of Mercury. Credit: Head lab / Brown University"]https://news.brown.edu/files/styles/hor ... alebar.jpg[/img3][hr][/hr]The scorching hot surface of Mercury seems like an unlikely place to find ice, but research over the past three decades has suggested that water is frozen on the first rock from the sun, hidden away on crater floors that are permanently shadowed from the sun’s blistering rays. Now, a new study led by Brown University researchers suggests that there could be much more ice on Mercury’s surface than previously thought.
The study, published in Geophysical Research Letters, adds three new members to the list of craters near Mercury’s north pole that appear to harbor large surface ice deposits. But in addition to those large deposits, the research also shows evidence that smaller-scale deposits scattered around Mercury’s north pole, both inside craters and in shadowed terrain between craters. Those deposits may be small, but they could add up to a lot more previously unaccounted-for ice. ...
The idea that Mercury might have frozen water emerged in the 1990s, when Earth-based radar telescopes detected highly reflective regions inside several craters near Mercury’s poles. The planet’s axis doesn’t have much tilt, so its poles get little direct sunlight, and the floors of some craters get no direct sunlight at all. Without an atmosphere to hold in any heat from surrounding surfaces, temperatures in those eternal shadows have been calculated to be low enough for water ice to be stable. That raised the possibility these “radar-bright” regions could be ice. ...
New evidence for surface water ice in small-scale cold traps and in three large craters at the north polar
region of Mercury from the Mercury Laser Altimeter - Ariel N. Deutsch, Gregory A. Neumann, James W. Head
- Geophysical Research Letters (online 14 Sep 2017) DOI: 10.1002/2017GL074723