 Shackleton is an impact crater that lies at the south pole of the Moon . The peaks along the crater 's rim are exposed to almost continual sunlight , while the interior is perpetually in shadow ( a Crater of eternal darkness ) . The low @-@ temperature interior of this crater functions as a cold trap that may capture and freeze volatiles shed during comet impacts on the Moon . Measurements by the Lunar Prospector spacecraft showed higher than normal amounts of hydrogen within the crater , which may indicate the presence of water ice . The crater is named after Antarctic explorer Ernest Shackleton . 
