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Between the news item of an asteroid giving Earth a close shave, and another new

ID: 1384050 • Letter: B

Question

Between the news item of an asteroid giving Earth a close shave, and another news item of the impending GRAIL impact ; I find myself wondering whether a NEO could be a hazard to Earth via the moon. I'm not sure this scenario is realistic. Perhaps such a large body may naturally be captured by Earth gravity instead of Lunar gravity before impact itself...

That is to say -

Could an NEO be

large enough &
have sufficient velocity

to impact on Luna so that fragments would

escape lunar gravity, and
make the down-hill run to Earth, and
remain large enough to cause loss of life/property on Earth?

Explanation / Answer

I guess you are referring to objects like 2012 DA14 which weighs about 130,000 metric tons.

DA14

Lunar meteorites have reached the Earth's surface before. So yes, it is possible.

There don't seem to be any large NEOs that have any significant chance of such an impact in the near future.

According to the UK Natural History Museum

There have been no recorded deaths due to a meteorite fall. A dog was, however, reputedly killed by the fall of the Nakhla martian meteorite in Egypt in 1911 and a boy was hit but not seriously injured by the fall of the Mbale meteorite in Uganda in 1992.

The Nakhla meteorite weighed about 10 kg.