Japan's Hayabusa2 mission delivers the first subsurface asteroid samples to Earth

A Japanese capsule returned to Earth on Saturday carrying a special delivery: the first rock samples from beneath the surface of an asteroid. When it plummeted to Earth, the capsule provided a stunning show above the Australian outback, streaking across the sky as a dazzling fireball. 

Project manager Yuichi Tsuda called the mission a "rare event in human history." It marks just the second time pristine, untouched material directly from an asteroid has been brought back to Earth. 

Japan's Hayabusa2 probe, which is roughly the size of a refrigerator, launched in December 2014, thrilling scientists when it landed on the diamond-shaped asteroid Ryugu, which means "dragon palace" in Japanese, located 185 million miles away. 

On Saturday, the probe successfully released a capsule for Earth, according to JAXA, Japan's national aerospace and space agency. The 15-inch capsule separated from the probe about 136,701 miles above Earth ahead of its planned descent into the Australian outback, near Woomera, South Australia. 

At 12:29 p.m. ET, the capsule streaked across the sky as a bright fireball. It was "slower than we expected," officials said during a live stream of the event. At 12:32 p.m. ET, the parachute successfully deployed and the direction searcher received a beacon radio wave signal from the capsule, indicating its location.

Shortly after, the capsule landed. The capsule landing point was estimated at 1:07 p.m. ET. 

The rescue mission lasted nearly two hours, as officials raced around the outback in search of the tiny capsule. At 2:47 p.m. ET, the team found the capsule and its parachute in the planned landing area, thanks to the helicopter search.

"The operation was perfect," JAXA tweeted. JAXA streamed the entire event live on Twitter and YouTube. Watch it here.  

Scientists expect the capsule to contain a small amount of asteroid material, collected last year, with the goal of learning more about the origins of the solar system and life on Earth. Scientists believe that the rocks that compose the asteroid are around four billion years old.  

The samples could shed light on "how matter is scattered around the solar system, why it exists on the asteroid and how it is related to Earth," Tsuda told reporters, according to a Friday news release.  

The samples were collected during two separate landings on Ryugu last year. During the first, the probe collected dust and blasted a hole in the asteroid's surface to find additional material beneath it. Several months later, the probe returned to the crater it created to collect more samples. 

"We may be able to get substances that will give us clues to the birth of a planet and the origin of life... I'm very interested to see the substances," mission manager Makoto Yoshikawa told reporters.

Now that the capsule has arrived, the samples will soon be processed and flown to Japan, then divided between researchers at JAXA, NASA and other international organizations. Some samples will be set aside for future studies when technology has further advanced. 

JAXA plans to extend Hayabusa2's mission for more than a decade, with its sights set on two new asteroids, 2001 CC21 and 1998 KY26. 

Soichi Noguchi, a JAXA astronaut currently aboard the International Space Station, tweeted that he saw the spacecraft fly past the ISS. "Just spotted #hayabusa2 from #ISS! Unfortunately not bright enough for handheld camera, but enjoyed watching capsule!"

The NASA OSIRIS-REx mission recently collected a sample from another near-Earth asteroid — Bennu, which is similar to Ryugu. The sample will return to Earth in 2023. 

In:
• Australia