TOKYO (AP) – They look like small pieces of charcoal, but the soil samples collected from an asteroid and returned to Earth by a Japanese spacecraft were hardly disappointing.
The monsters Japanese space officials described Thursday are as big as 1 centimeter (0.4 in) and rock hard, they don’t break when picked up or poured into another container. Smaller black, sandy grains that the spacecraft collected and returned separately were described last week.
The Hayabusa2 spacecraft took the two sets of samples last year from two locations on the asteroid Ryugu, more than 300 million kilometers (190 million miles) from Earth. He dropped them from space on a target in the Australian outback and the samples were brought to Japan in early December.
The grains of sand described by the Japan Aerospace Exploration Agency last week came from the spacecraft’s first landing in April 2019.
The larger fragments came from the compartment allocated for the second landing on Ryugu, said Tomohiro Usui, a space materials scientist.
To get the second set of samples in July last year, Hayabusa2 dropped an impactor to shoot beneath the asteroid’s surface, collecting material from the creator so that it wouldn’t be affected by space radiation and other environmental factors.
Usui said the differences in size indicate different hardness of the rock on the asteroid. “One possibility is that the site of the second touchdown was a hard surface and larger particles broke and entered the compartment.”
JAXA is continuing the initial investigation of the asteroid samples pending more complete studies next year. Scientists hope the samples will provide insight into the origins of the solar system and life on Earth. After studies in Japan, some samples will be shared with NASA and other international space agencies for additional research.
Hayabusa2, meanwhile, is on an 11-year expedition to another small and distant asteroid, 1998KY26, to try to study possible defenses against meteorites that could fly to Earth.
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