Japan’s asteroid sample returns home, poised to reveal solar system’s secrets

It surprised, dazzled, then disappeared in a flash. In the early hours of Sunday morning, the sample capsule of Japan’s Hayabusa2 spacecraft plunged through the atmosphere over the mining town of Coober Pedy in South Australia, blazing an ephemeral trail of fire through the sky.

Above the Lookout Cave Motel in the center of town, just before 4 a.m. local time (9:30 a.m. PT on Saturday), about a dozen people gathered and mingled. Tripods were erected and camera equipment was fine-tuned and pointed at the sky. Then, without a sound, a twinkling point of light appeared out of the dark. It moved quickly. The crowd erupted with “oohs,” and some pointed their phones at the sky.

Among those wowed by the show were 34-year-old Ross, from Townsville, Queensland, and his two sons, 6-year-old Max and 8-year-old Chase. “It was pretty cool,” Ross said. “It was worth getting up early for.”

Locked within the capsule was the first ever subsurface sample from an asteroid. The Japan Aerospace Exploration Agency confirmed that the 16-inch container had touched down on the flat, ochre plains of the Woomera Prohibited Area (WPA) more than 200 miles southeast of Coober Pedy at approximately 4:37 a.m. local time. 

The landing was the culmination of a decade of work by JAXA scientists and engineers, and it came six years after Hayabusa2, which is about the size of two washing machines slapped together, departed Earth. The spacecraft traveled over 3.2 billion miles on its journey to near-Earth asteroid Ryugu and back, spending over a year using specialized cameras, radar and an infrared imager to survey the spinning top-shaped rock. On two occasions in 2019, it collected samples from the surface in brief snatch-and-go maneuvers.

Masaki Fujimoto, deputy director of JAXA’s Institute for Space and Astronautical Science, says the mission has been one of the defining moments of his life, As it came to a close, it was obvious the stunning finale and recovery operations would be bittersweet.

“This is the last time we will all be together,” Fujimoto said. 

But the mission isn’t quite over yet. The recovery of the capsule took place in the predawn dark of the outback, and confirmation of the capsule’s collection was confirmed early on Dec. 6. Initial analysis occurred in Woomera. The team then shipped the capsule via a chartered flight from Australia to Japan, where it will be ferried to JAXA for further analysis.

Outback adventure

The Australian Space Agency and the country’s Department of Defence played a significant role in the capsule’s safe return. The Defence Department manages the Woomera Prohibited Area, a huge swath of land, about half the size of the UK, where the capsule was guided after release from Hayabusa2 on Saturday. Road closures kept residents from passing through the region for almost 12 hours, as a precautionary measure.

JAXA engineers tightened the final landing zone to an area about one-tenth that size, with some deft maneuvering while the spacecraft was traveling back to Earth. 

The sample entered the Earth’s atmosphere moving at 7.5 miles per second, but as it hit the dense atmosphere it slowed down to around 110 yards per second, throwing off its heat shield and deploying its parachute. After gliding for about 20 minutes, it landed on the red, Mars-like plains of the WPA. 

To help locate the sample capsule, members of the Defence Force locked on to it as it first began burning through the atmosphere, tracking it with ground cameras and radar. This enabled the JAXA team to locate the sample and send its helicopter team to fly out and collect it at approximately 4:47 a.m. The first person who had the honor of touching the capsule was a safety officer, says Satoru Nakazawa, who led the recovery mission.

Once it acquired the capsule, the recovery team quickly ferried it to a pop-up laboratory within the Woomera Range Operations Center, known as the Quick Look Facility, or QLF.

What’s in the box?

The team estimates that Hayabusa2 collected about one gram of material from Ryugu, based on observations from the spacecraft’s cameras. Confirmation of exactly what was nabbed during Hayabusa2’s two heists is expected over the coming weeks. 

JAXA’s specialist retrieval team located the capsule at approximately 5:34 a.m. local time and took it back to the QLF for testing. According to JAXA’s Hayabusa2 Twitter account, all operations ended at 6:01 a.m. “The…