This shaded relief image shows the moon’s Shackleton Crater, situated near to the Lunar south pole, which is permanently shadowed. The interior structure is illustrated in colour based on data from NASA’s LRO probe.
Credit: NASA/GSFC/SVS

“A team of researchers lead by Bill Farrell of NASA Goddard Space Flight Center in Greenbelt, MD, investigated how volatile chemicals like water ice, carbon monoxide, carbon dioxide, ammonia, methane and other unstable compounds (collectively referred to as “volatiles”) can migrate out of craters on the Moon.

Many volatiles escape into space, but some of them are bounded to the Moon, often falling into “cold traps” in the bottom of permanently shadowed craters. The scientists looked at how volatiles are released when bombarded by energetic particles that are common in the harsh space environment. Plasma from the solar wind and micrometeorite impacts may vaporize volatiles lofting them up from the crater floors and scattering them in the crater’s immediate vicinity”

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shackleton crater