Scientists find water in samples from asteroid Ryugu brought back to Earth

The discovery supports the theory that the building blocks of life on Earth may have arrived from outer space via asteroids.


Japanese scientists have revealed that samples from the asteroid Ryugu hold water inside.

The discovery was made thanks to the analysis of 5.4 grams of stones and dust that the Hayabusa-2 probe collected from Ryugu.

Life could have reached Earth

One drop of water was extracted from the sample .

“This drop of water has great significance,” lead scientist Tomoki Nakamura of Tohoku University told reporters ahead of the research’s publication in the journal Science .

Hayabusa-2 launched in 2014 on its mission to Ryugu and returned to Earth orbit two years ago to drop off a capsule containing the sample.

The prized cargo has already yielded several insights, including organic material that showed that some of the building blocks of life on Earth, amino acids, may have formed in space.

The team’s latest discovery was a drop of fluid in the Ryugu sample “which was carbonated water containing salt and organic matter,” Nakamura said.

That bolsters the theory that asteroids like Ryugu  could have “provided water , which contains salt and organic matter” in collisions with Earth.

“We have uncovered evidence that this may have been directly related to, for example, the origin of the oceans or organic matter on Earth.”

Further discoveries await

Nakamura’s team, which is made up of about 150 researchers, including 30 from the US, Britain, France, Italy and China, is one of the largest teams to analyze the Ryugu sample .

The sample has been divided among different scientific teams to maximize the possibility of new discoveries.

“The fact that water was discovered in the sample itself is surprising,” given its fragility and the potential for it to be destroyed in outer space, said Kensei Kobayashi, an astrobiology expert and professor emeritus at Yokohama National University. “It suggests that the asteroid contained water , in the form of fluid and not just ice, and that organic matter may have been generated in it.”