Lunar water true, this would indicate that the neutron results from Lunar Prospector were primarily from hydrogen in forms other than ice, such as trapped hydrogen molecules or organics. Nevertheless, the interpretation of the Arecibo data do not exclude the possibility of water ice in permanently shadowed craters. In June 2009, NASA's "Deep Impact" spacecraft, now redesignated EPOXI, made further confirmatory bound hydrogen measurements during another lunar flyby. As part of its lunar mapping programme, Japan's Kaguya probe, launched in September 2007 for a 19-month mission, carried out gamma ray spectrometry observations from orbit that can measure the abundances of various elements
Explorer 18 Explorer 18 Explorer 18, also called IMP-A, IMP 1 and S-74, was an American satellite launched as part of Explorers program. Explorer 18 was launched on 27 November 1963 from Cape Canaveral, Florida, United States, with Delta rocket. Explorer 18 was the first satellite of the Interplanetary Monitoring Platform. Explorer 18 was a solar cell and chemical-battery powered spacecraft instrumented for interplanetary and distant magnetospheric studies of energetic particles, cosmic rays, magnetic fields, and plasmas. Initial spacecraft parameters included a local time of apogee of 1020 hours, a spin rate of 22 rpm, and a spin direction of 115° right