Scientists have been sampling dust grains from the Saturn region with the Cassini spacecraft, and they’ve made an incredible discovery: some of them came from outside the Solar System.

After analyzing millions of dust grains, a total of 36 of them appear to have an interstellar origin, according to a NASA statement.

Cassini has been orbiting around Saturn for the last 12 years, taking most of the dust it has been sampling from the moon Enceladus. Scientists first discovered intellar dust back in the 1990s, and had always hoped to detect them near Saturn.

Scientists suspect that these dust grains are from another part of spae because they travel at a much higher rate of speed and in a specific path different from the grains that are normally collected around Saturn.

The dust was typically traveling at around 45,000 miles per hour before getting caught in Saturn’s gravity.

“From that discovery, we always hoped we would be able to detect these interstellar interlopers at Saturn with Cassini. We knew that if we looked in the right direction, we should find them,” said Nicolas Altobelli, Cassini project scientist at ESA (European Space Agency) and lead author of the study, in the statement. “Indeed, on average, we have captured a few of these dust grains per year, travelling at high speed and on a specific path quite different from that of the usual icy grains we collect around Saturn.”

“Cosmic dust is produced when stars die, but with the vast range of types of stars in the universe, we naturally expected to encounter a huge range of dust types over the long period of our study,” added Frank Postberg of the University of Heidelberg, a co-author of the paper and co-investigator of Cassini’s dust analyzer.