Possible origin of lunar ice

The comet hypothesis of the origin of lunar ice, which was recently discovered in the polar regions of the moon by Lunar Prospector, is examined. It is shown that a comet impact produces a temporary atmosphere whose volatile component. accumulates essentially completely in cold traps - the permanently shadowed regions of the Moon. The condensation of volatile compounds leads to the formation of ice with a definite chemical and isotopic composition, which contains important information about the composition of the comet: This hypothesis can be checked during the next lunar missions, and if confirmed, detinite progress will have been made in understanding the nature of comets. Published by Elsevier Science Ltd on behalf of COSPAR.