TOKYO (AP) – They look like small chunks of coal, but soil samples collected from an asteroid and brought back to Earth by a Japanese spacecraft were not disappointing.
The specimens described by Japanese space officials Thursday were 1 cm (0.4 in) in size and solid rock, and don’t break when captured or poured into another container. Small black sand pellets collected by the spacecraft and returned separately were described last week.
The Hayabusa2 spacecraft obtained two sets of samples last year from two locations on the asteroid Ryugu, more than 300 million kilometers (190 million miles) from Earth. I dropped it from space on a target in the Australian outback, and brought the samples to Japan in early December.
The sand particles described by the Japan Aerospace Exploration Agency last week were from the spacecraft’s first landing in April 2019.
Space materials scientist Tomohiro Usui said the larger fragments were from the cabin designated for the second landing on Ryuju.
To obtain the second set of samples in July last year, Hayabusa2 dropped an explosive collider beneath the asteroid’s surface, collecting material from the rig so it was not affected by space radiation and other environmental factors.
Usui said that the differences in size indicate a different stiffness of the bedrock on the asteroid. “One possibility is that the second landing site was solid rock and the larger particles broke off and entered the cabin.”
JAXA continues preliminary examination of asteroid samples before conducting full studies next year. Scientists hope the samples will provide insight into the origins of the solar system and life on Earth. After studies have been conducted in Japan, some samples will be shared with NASA and other international space agencies for further research.
Meanwhile, Hayabusa2 is on an 11-year expedition to another small and distant asteroid, 1998KY26, to try to study potential defenses against meteorites that could fly toward Earth.
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