Traces of mysterious planet Theia have been found on the surface of Earth’s Moon.
Boffins have analysed samples of rock brought back by Apollo astronauts, and claimed they contain bits of another world. The discovery appears to back up the theory that the Moon was formed when Theia slammed into Earth some 4.5 billion years ago.
Lead researcher Dr Daniel Herwartz, from the University of Goettingen, said that people were beginning to doubt the prevailing theory.
“It was getting to the stage where some people were suggesting that the collision had not taken place,” he told the BBC.
“But we have now discovered small differences between the Earth and the Moon. This confirms the giant impact hypothesis.”
To confirm the theory, Dr Herwartz analysed the isotopes of the oxygen in the moon rocks, which serves as a sort of fingerprint. A meteorite, for instance, shows a markedly different ratio of oxygen isotopes than rock from the earth.
The doc and his colleagues have published their research in hefty boffnry mag Science.
The Moon was probably formed by a catastrophic collision of the proto-Earth with a planetesimal named Theia.
However, the rocks from Theia look to be fairly similar to that of the earth, which has baffled other scientists.
Dr Mahesh Anand from The Open University said the research was “exciting” but urged caution.
“We have to be cautious about representativeness of these rocks of the entire Moon, and so further analysis of a variety of lunar rocks is required for further confirmation,” he said. ®