The largest asteroid sample ever collected in the United States

First Amendment: 09/24/2023 – 18:21Last update: 09/24/2023 – 18:19

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The fall, which was detected by military sensors, was stopped by two parachutes.

The sample taken in 2020 from the asteroid Bennu contains about 250 grams of matter, according to estimates by the US Space Agency, much more than the two previous asteroid samples collected by Japanese missions.

Space Agency head Bill Nelson emphasized that this material “will help better understand the types of asteroids that could threaten Earth” and shed light on “the very beginning of the history of the solar system.”

NASA scientist Amy Simon told AFP before landing that it was “the largest sample of lunar rock we have extracted” from the Apollo program, which ended in 1972.

About four hours before it was scheduled to land, the Osiris-Rex probe released the capsule containing the sample, more than 100,000 kilometers from Earth.

During the last 13 minutes, this capsule passed through the atmosphere: it entered at a speed of more than 44,000 km/h and reached a temperature of 2,700 degrees Celsius. The probe continued its mission towards another asteroid.

Two Japanese samples

Once the capsule arrived on Earth, a team equipped with gloves and masks checked its condition, before placing it in a net and lifting it towards a helicopter.

The capsule should be exposed to the desert sand for the shortest time possible to avoid any contamination of the sample that could distort subsequent analyses.

The sample will be transported on Monday to the Johnson Space Center in Houston, Texas. There the box will be opened in another sealed room. The process will take days.

NASA plans to hold a press conference on October 11 to reveal the initial results.

Most of the sample will be preserved for future generations to study. About 25% will be used immediately for trials and a small portion will be shared with partners Japan and Canada.

Japan gave NASA fragments from the Ryugu asteroid, of which it recovered 5.4 grams in 2020, during the Hayabusa-2 mission. In 2010, a microscopic amount of another asteroid was reported.

Bennu’s sample is “much larger, so we will be able to do more analyses,” Simon said.

History of our origin

Asteroids are composed of the original material of the solar system, which, unlike Earth, has remained intact. It contains “clues about how the solar system formed and evolved,” explained Melissa Morris, director of NASA’s Osiris-Rex program. “It’s our origin story.”

By colliding with our planet, “we believe that asteroids and comets brought with them organic materials, and perhaps water, that helped develop life on Earth,” Simon said.

Scientists believe that Bennu (500 meters in diameter) is rich in carbon and contains water molecules coated with minerals.

The asteroid’s surface turned out to be less dense than expected. A better understanding of their composition could be useful in the future.

There is a small risk (one chance in 2700) that Bennu will hit Earth in 2182, which would be catastrophic. In 2022, NASA was able to divert an asteroid by colliding with it.

© 2023 Agence France-Presse