... Tonight's Sky . ... Searching.. ... Sky this Month . ... Researchers estimate ice content of crater at Moon's south pole . ... NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft has returned data that indicate ice may make up as much as 22 percent of the surface material in a crater located on the Moon's south pole. ... Like several craters at the Moon's south pole, the small tilt of the lunar spin axis means Shackleton Crater's interior is permanently dark, and therefore extremely cold. ...