When our young planet was taking a beating by massive impacts, bits were ejected into space—and some ended up on the moon.
An artist’s impression of what our planet probably looked like over 4 billion years ago, during the violent Hadean epoch [Simone Marchi (SwRI), SSERVI, NASA]
This is an interesting thought: When Apollo astronauts were busy exploring the lunar surface, it wasn’t just moon rocks that were crunching beneath their moon boots—bits of Earth were there too. But how did Earth stuff get mixed-in with moon stuff?
According to a new study published in the journal Earth and Planetary Science Letters, this question may be a controversial one, but it’s not without some compelling evidence.
During the Apollo 14 moon landing in February 1971, when NASA astronauts Alan Shepard and Ed Mitchell were exploring the Fra Mauro Highlands, they scooped up some moon rocks and returned them to Earth for study. Fast-forward 48 years and an international group of researchers think that a 2 gram shard of rock in one of their scoops has terrestrial origins. That is a cool find in itself, but this particular sample is ancient, and possibly the oldest sample of Earth ...