Scientists will soon have access to samples from a box of moon rocks that no one has opened since Neil Armstrong sealed it on the moon 50 years ago:
The upcoming experiments, on vacuum-sealed cores and a long-frozen rock, can be performed only once, at the precise moment the samples are opened. That’s why the materials have been held back since they were retrieved from the moon, said Ryan Zeigler, who curates the Apollo rocks collection. NASA was waiting for the right scientists, with the right technologies, at the right time.
With Apollo 11’s 50th anniversary this year and renewed interest in the moon ahead of a proposed return mission, Zeigler said, the right time is now.
Before the Apollo 11 mission, scientists couldn’t agree on where the moon came from. It’s a misfit in the solar system — much larger relative to its planet than almost any other moon. Some speculated that it was once an independent object that was “captured” by Earth’s gravity. Others proposed that the satellite formed in orbit alongside Earth when the planets were coalescing out of a primordial dust disc. Many grade-school textbooks taught that it was, in fact, a blob of Earth that had been flung away by our planet’s spin; the Pacific Ocean was thought to be a scar from this ancient loss.
All of those theories had to be discarded as soon as scientists saw the first Apollo rocks.
About 4.5 billion years ago, the theory goes, a long-gone giant planet called Theia, named for the mother of the Greek moon goddess, smashed into the newly formed Earth. The impact shattered both Theia and the proto-Earth and splashed millions of tons of material into space. Some of the rock coalesced in orbit around the Earth, and our satellite was born. The heaviest bits sank to the moon’s center, while the light minerals floated to the top of the worldwide magma ocean and crystallized, forming the thin anorthosite crust. The rocks and dust retrieved by Armstrong and Scott are relics of this long-ago tumult.
How cool! And how loony, in a sense. I can't wait to see whether they get evidence in support of the hypothesis.