Water found in asteroid dust may help to understand how life appeared on Earth
The Japanese space probe extracted dust particles from an asteroid at a distance of about 300 million kilometers from Earth, in which a drop of water was found. This discovery may become another argument in support of the theory of the cosmic origin of life on Earth, reports The Guardian.
“This drop of water has great meaning,” the lead scientist, Tomoki Nakamura of Tohoku University, told reporters before the publication of the research in the journal Science on Friday. It was based on an analysis of 5.4 grams of rocks and dust collected by the Hayabusa-2 probe from the Ryugu asteroid.
Hayabusa-2 was launched in 2014 on a mission to Ryugu and returned to Earth orbit two years ago to drop a sample capsule. Organic material was found in the dust, which showed that some of the building blocks of life on Earth, amino acids, may have been formed in space. The team’s latest discovery was a drop of liquid in Ryugu’s sample, “which was carbonated water containing salt and organic matter,” Nakamura said.
This, he said, supports the theory that asteroids like Ryugu or its larger parent asteroid could have “provided water, which contains salt and organic matter” in collisions with Earth.
Nakamura’s team of about 150 researchers — including 30 from the US, UK, France, Italy, and China — is one of the largest teams analyzing the sample from Ryugu. It was distributed among different scientific groups so that the chances of new discoveries were maximized. Astrobiology expert and Yokohama National University professor emeritus Kensei Kobayashi, who is not part of the research team, welcomed the discovery.
“The fact that water was discovered in the sample itself is surprising,” given its fragility and the likelihood of its destruction in space, he said. “It does suggest that the asteroid contained water, in the form of fluid and not just ice, and organic matter may have been generated in that water.”