Earth's water could come from asteroids, Hayabusa-2 samples suggest

• Scientists say new asteroid sample findings suggest water on Earth may have come from asteroids.
• They studied samples collected by Japan's Hayabusa-2 asteroid mission.
• The Hayabusa-2 space probe is now on its way to another asteroid for investigation.

A recent press statement reveals that water, one of the key components enabling life to flourish on Earth as we know it, may have come from asteroids originating in the outer edges of the solar system.

Scientists made the observations after analyzing samples collected from the Japanese space agency, JAXA's, Hayabusa-2 mission. That six-year space mission sent a space probe to collect 5.4 grams (0.2 ounces) of rocks and dust from the asteroid Ryugu. Hayabusa-2 dropped the samples back into Earth's atmosphere in December 2020.

New Ryugu asteroid sample findings

The Hayabusa-2 mission's goal was to investigate an asteroid that could potentially shed new light on the early formation of the Solar System. Now, new studies are starting to emerge based on investigations and analyses of the Ryugu samples collected by JAXA.

In a new paper published in the journal Nature Astronomy, scientists said the samples suggest asteroids may have been one of the primary sources of water during the Earth's early formation. "Ryugu particles are undoubtedly among the most uncontaminated Solar System materials available for laboratory study, and ongoing investigations of these precious samples will certainly expand our understanding of early Solar System processes," the study explains.

In June, another study highlighted organic material found on Ryugu, suggesting the building blocks of life, amino acids, may have come from asteroids.

In the new study, published Monday, August 15, the scientists wrote that "volatile and organic-rich C-type asteroids may have been one of the main sources of Earth's water. The delivery of volatiles (organics and water) to the Earth is still a subject of notable debate."

Crucially, the organic materials discovered "in Ryugu particles, identified in this study, probably represent one important source of volatiles." The scientists say these materials may have had an "outer Solar System origin," though they concede that they were "unlikely to be the only source of volatiles delivered to the early Earth."

Investigating asteroids

Hayabusa-2 was launched in 2014. During its six-year mission, the space probe traveled approximately 300 kilometers before returning to Earth's orbit to drop off a capsule that contained the sample it had collected. The capsule deployed a parachute a short while after reentering Earth's atmosphere and landed safely in South Australia. A recovery team searched the capsule's landing site before finding the sample, which was said to be in great condition.

As for the Hayabusa-2 space probe, it's currently on another sample-collecting mission. After dropping the Ruygu sample capsule, the spacecraft avoided reentry, and it is now traveling to a smaller, 30m-wide asteroid, with arrival scheduled for 2031.

Another high-profile asteroid mission, NASA's Double Asteroid Redirection Test (DART), is making its way to an asteroid named Dimorphos to test whether a spacecraft can successfully alter a hazardous asteroid's trajectory.