Some 20 years ago, researchers discovered ancient stardust buried deep in the floor of the Pacific Ocean.

They deduced that the stardust – actually a substance called iron 60 that that comes mostly from the explosions of giant stars in outer space – had rained down onto Earth over millions of years.

Now, the same cosmic substance has been found in snow at the South Pole. The difference? The snow is only about 20 years old, meaning this stardust fell down to Earth within the last two decades.

"It must have been a supernova, not so near as to kill us but not too far to be diluted in space," said Dominik Koll, a physicist at Australian National University in Canberra and lead author of the study, according to Inside Science. Findings from the study were published this month in the journal Physical Review Letters.

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Koll said it's "the first evidence that someone saw something that recent." By recent, he means the vast amount of time that it could take tiny, minute particles to travel through space from a supernova light years away.

Koll and a team of researchers melted, strained and studied more than a half-ton of snow shipped to them frozen from Antarctica, according to a press release from the Alfred Wegener Institute Helmholtz Center for Polar and Marine Research in Germany, where the research was conducted. The 25 boxes of snow traveled first by plane and then by ship, and finally made its way to the center.

The scientists say it will take more research, and digging deeper into the Antarctic ice and snow, to determine when and where the stardust formed.