Tokyo – They resemble small fragments of coal, but soil samples collected from asteroids and returned to Earth by a Japanese spacecraft were hardly disappointing.
The specimens described by Japanese space officials on Thursday are only 0.4 inches in size and hard as stone, they don’t break when picked up or poured into another container. Smaller black, sand granules that the spacecraft collected and returned separately were described last week.
Last year, the Hayabusa2 spacecraft received two sets of samples from two locations on the asteroid Ryugu, more than 190 million miles from Earth. They were thrown from space at a target in the Australian hinterland, and the samples were brought to Japan in early December.
The sand granules that the Japanese space research agency researched last week were from the first arrival of the spacecraft on the asteroid, in April 2019.
The larger fragments are from the section allocated for the second touch of Ryugu, said Tomohiro Usui, a space materials scientist.
To get a second set of samples in July last year, Hayabusa2 threw an impact element to explode beneath the asteroid’s surface, collecting material from the crater so it would not be affected by space radiation and other environmental factors.
Usui said the differences in size suggest different hardness of the bedrock on the asteroid. “One possibility is that the site of the second contact was a hard surface, and larger particles broke and entered the compartment.”
JAXA continues initial testing of asteroid samples ahead of more complete studies next year.
Scientists hope that the samples will provide insight into the origin of the solar system and life on Earth.
After studying in Japan, some of the samples will be shared with NASA and other international space agencies for further research.
Meanwhile, Hayabusa2 is on an eleven-year expedition to another small and distant asteroid, 1998KY26, to try to study a possible defense against meteorites that could fly toward Earth.