Evidence for Lunar ice
Lunar Prospector orbited Moon
- measured neutrons
- solar wind impacts lunar surface
- creates radioactive substances
- subsequent decay gives off neutrons
- Neutrons observed to be slower near N and S poles
- indicates H is present near surface
- H good moderator of neutrons because of low mass
- Most probable source of H is H2O ice
- silicate rocks have no H (unless hydrated)
- H2O ice dominant constituent of comets
- crater floors cold enough to freeze and trap H2O
- few months ago crash landed near one of these craters
- hoped to knock icy debris into space
- Many telescopes on earth trained on event