Japanese space capsule carrying pristine asteroid samples lands in Australia
For the second time ever, humanity has brought asteroid samples down to Earth.
A small capsule bearing pristine pieces of the near-Earth asteroid Ryugu touched down early this afternoon (Dec. 5) within the remote and rugged Woomera Prohibited Area, about 310 miles (500 kilometers) northwest of the South Australian capital of Adelaide. The samples were snagged millions of miles from Earth by Japan's Hayabusa2 mission, which studied the 3,000-foot-wide (900 meters) Ryugu up close from June 2018 to November 2019. Hayabusa2's predecessor was the first to haul space-rock samples home, delivering pieces of the stony asteroid Itokawa in 2010. But the original Hayabusa (Japanese for "peregrine falcon") returned less than 1 milligram of material. Hayabusa2's bounty is expected to exceed 100 mg (0.0035 ounces), and its samples come from a very different kind of asteroid — a primitive "C-type" space rock rich in water and carbon-containing organic compounds.
"The materials that formed the Earth, its oceans and life were present in the primordial cloud from which our solar system formed. In the early solar system, these materials were in contact and able to chemically interact within the same parent objects," Japan Aerospace Exploration Agency (JAXA) officials wrote in an overview of Hayabusa2.
"These interactions are retained even today in primitive bodies (C-type asteroids), so returning samples from these bodies for analysis will elucidate the origins and evolution of the solar system and the building blocks of life," they added.
Having the samples here on Earth is key; scientists in well-equipped labs around the world can scrutinize the cosmic rock in far greater detail than Hayabusa2, or any other probe on its own in deep space, ever could. The returned material's purity is also a major selling point. Researchers already have access to many meteorites, but these "free samples" of asteroids have been significantly altered by their trip through Earth's atmosphere and their time on our planet's surface. The 1,340-lb. (690 kilograms) Hayabusa2 spacecraft launched in December 2014 and rendezvoused with the rugged Ryugu on June 27, 2018, kicking off an epic exploration campaign.
Hayabusa2 observed Ryugu in detail and also deployed multiple miniprobes onto the asteroid's surface — several tiny, hopping rovers and a microwave-sized lander called MASCOT (Mobile Asteroid Surface Scout), which was provided by the German Aerospace Center in collaboration with the French space agency CNES.
The main Hayabusa2 spacecraft made two trips of its own to Ryugu's surface, both times to snag samples. During the first of these operations, in February 2019, Hayabusa2 scooped up some surface material. In April of that year, the spacecraft fired a 5.5-lb. (2.5 kg) copper projectile at Ryugu, blasting a 33-foot-wide (10 m) crater into the asteroid's surface. Then, that July, the probe swooped down and collected some of this recently excavated dirt and rock.
Hayabusa2 kept these two samples separate, so scientists will be able to compare material from two very different environments — Ryugu's surface, which is weathered by space radiation, and the asteroid's more protected depths.
https://www.space.com/japan-hayabusa2-asteroid-samples-land-australia