A team of scientists has detected tiny quantities of the unreactive volcanic trace gases Krypton and Xenon in Earth's mantle, which reveal an isotopic 'fingerprint' matching that of
meteorites.

The researchers say this means the gases that formed the Earth's atmosphere - and probably its oceans - did not come from inside the Earth but from outer space.

The report published this week in the journal Science demonstrates that the age-old view that volcanoes were the source of the Earth's earliest atmosphere must be put to rest, the researchers suggest.