TOKYO (AP): They look like small fragments of charcoal, but soil samples collected from an asteroid and returned to Earth by a Japanese spacecraft were hardly disappointing.
The samples the Japanese space officers described on Thursday are up to 1 centimeter (0.4 inches) and are hard, without breaking when picked up or dumped in another container. Smaller black and sandy granules were described last week that the probe collected and returned separately.
The Hayabusa2 spacecraft obtained the two sets of samples last year from two sites on the asteroid Ryugu, more than 300 million kilometers (190 million miles) from Earth. He dropped them from space into an Australian Outback target and the samples were taken to Japan in early December.
The sandy granules that the Japan Aerospace Exploration Agency described last week came from the spacecraft’s first touchdown in April 2019.
The larger fragments came from the compartment assigned for Ryugu’s second touchdown, said Tomohiro Usui, a space materials scientist.
To obtain the second set of samples in July last year, Hayabusa2 launched an impactor to explode below the asteroid’s surface, collecting artifact material so that it would not be affected by space radiation and other factors. environmental.
Usui said the differences in size suggest a different hardness from the asteroid’s parent rock. “One possibility is that the site of the second touchdown was a hard rock and larger particles would break and enter the compartment.”
JAXA continues the initial examination of asteroid samples before more complete studies next year. Scientists expect the samples to provide information about the origins of the solar system and life on Earth. Following studies in Japan, some of the 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, distant asteroid, 1998KY26, to try to study possible defenses against meteorites that could fly to Earth.
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