Scientists in Sweden have unearthed a meteorite which doesn’t match anything in their labs. The chemical composition of the tennis-ball sized piece of space rock is positively ‘alien’.
And that’s saying something given some 50,000 meteorites have been found and examined around the Earth.
“This does not resemble anything ... even if we look at the big types that exist today and look at the broad ranges, this one falls completely outside of everything,” says Birger Schmitz of Sweden’s Lund University.
The meteorite was found fossilised in 470 million-year-old limestone rock in a Swedish quarry. They were digging up part of an ancient sea bed to turn into floor tiles.
Only now are we beginning to appreciate what it may represent.
Most meteorites, roughly 85 per cent, belong to a class called ‘ordinary chondrites’. These are believed to have all come from a single enormous asteroid, smashed and sent hurtling across the solar system by a collision billions of years ago.
These can all be identified by their chemical ‘fingerprint’ — a unique combination of chromium and oxygen isotopes.
For decades scientists have been seeking pieces of the second asteroid involved in that same collision.
Nothing has ever been found.
Until now.
Schmits says: “One day the student came back and said, ‘One of these you’ve given me is something completely different.’ So he showed me the grains and we were completely puzzled. We had no clue, no idea what it could be. It was found in 2011 and it has taken five years to find out what it is.”
The chemical ‘fingerprint’ of the object — categorised as Österplana 65- was completely new.
It doesn’t match any other known meteorite.
It doesn’t match anything known on Earth.
It doesn’t match anything known on Mars.
It is, in all ways, alien.
The results of their analysis have been published in the science journal Nature Communications.
“All interpretations about how the solar system formed are based on the meteorites that fall on earth today. And 80 per cent are ordinary chondrite and the assumption is then that these meteorites are the type of material that dominates ... that it’s typical material for the solar system. But now we have the very, very first little clue, or indication, that there may have been other meteorites that were more common in the Earth’s distant past,” Schmitz says.
“The meteorites found on Earth today apparently do not give a full representation of the kind of bodies in the asteroid belt 500 million years ago.”
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