CAPE CANAVERAL, Fla., July 19 (UPI) -- NASA scientists are resurrecting plans for a moon mission to return samples to Earth from a crater that is believed to be the oldest impact basin in the solar system.
The South Pole-Aitken Basin Sample Return mission was proposed to NASA several years ago, but failed to secure funding under the agency's low-cost Discovery programs, which are capped at $350 million each. A key scientific advisory panel, however, recently endorsed the proposal and NASA is expecting it to be included in its New Frontiers program, which allots up to about $700 million per mission.
"It seems unlikely that someone would not propose it," New Frontiers program scientist Thomas Morgan said in an interview with United Press International.
The mission, seen as a technology testbed for a Mars sample return flight, would be built around the quest for ancient rocks and soils that were expelled from deep inside the moon by a high-speed and massive collision with an ancient asteroid or meteor.
"There's a debate going on about the early cratering history of the moon," said Paul Spudis, a geologist and deputy directory of the Lunar and Planetary Institute in Houston.
"It is hypothesized that the moon and Earth were barraged 3.9 billion to 4 billion years ago. If you look at the samples from the lunar highlands, all the impact melts show that age. We don't know why the planets would have formed 4.6 billion years ago, be bombarded with impacts and then suddenly stop," he said.
If samples from the crater's depths turn out to be about the same age as the highlands rocks, scientists would have an important insight into what was happening to early Earth at that time, too.
"The Earth and moon have the same bombardment rate, but Earth has no rocks preserved from that period," said Spudis. "We think that that time is roughly when life emerged."