Hayabusa2’s asteroid sample ‘treasure box’ has been opened for the first time
The Japan Aerospace Exploration Agency, JAXA, has cracked open the recently-returned sample capsule of Hayabusa2 and found treasures from deep space waiting inside. On Monday, the agency revealed the first images of material collected from near-Earth asteroid Ryugu.
Hayabusa2 is JAXA’s asteroid-chasing spacecraft, which spent 16 months around Ryugu between 2018 and 2019. In that time, the spacecraft made two touchdowns on the asteroid’s surface, collecting rocks and debris from its face and storing them in a sample capsule, informally known as the tamatebako or “treasure box.”
Hayabusa2 then returned the treasure box to Earth on Dec. 6, gently landing it in the Australian outback. JAXA scientists located and moved the container to a makeshift laboratory known as the “Quick Look Facility,” QLF, where it underwent tests designed to find trace gases in the container. This first look suggested the team had captured gas — but they couldn’t be sure if it came from Ryugu or from Earth.
On Monday, JAXA revealed the gas detected by Hayabusa2 was indeed from Ryugu. A secondary analysis provided the same readout as seen at the QLF, confirming it is of extraterrestrial origin. This is the first time a gas sample has been collected from deep space.
But that wasn’t all. The agency also provided definitive evidence Hayabusa2 has captured material from the surface of the asteroid.
The spacecraft’s sample capsule contains three chambers — A, B and C — for storing material picked up on Ryugu. The first touchdown is expected to have trapped material in chamber A, while the second touchdown should have kicked up rock into chamber C.
JAXA was confident sampling had occurred successfully during Hayabusa2’s landing attempts on Ryugu last year. On Sunday, the agency cracked open the container and found a fine, black grain on the outside of the main chambers. A good start.
During a press conference on Monday, JAXA revealed even more. At a purpose-built facility in Sagamihara, Japan, JAXA scientists opened chamber A. At around 11 a.m. local time, pieces of Ryugu were observed for the first time.
The sample return is a monumental achievement for the diminutive space agency and is poised to help answer some of the biggest questions in space science. When the solar system was forming, some 4.6 billion years ago, all of the materials that make it up were circling the sun in a huge cloud of dust and debris. Asteroids, like Ryugu, provide a way to understand that history because they are relics of the ancient solar system. Studying their composition gives us a window to that past — providing a way to understand how the Earth, and maybe even how we, came to be.
The capsule opening is merely the beginning of that journey through time. JAXA will open chamber C in coming days and then start to assess the recovered samples using an optical microscope and observing the spectra in infrared. In early 2021, the first details of the analysis will trickle out. At the end of 2021, the samples will be shared with other space agencies, including NASA. Collaborating with international space agencies will maximize the science output from the sample, which JAXA currently estimates to be around 1 to 2 grams.
Hayabusa2 isn’t the only asteroid sample return mission underway. NASA’s Osiris-rex spacecraft aims to replicate the successes of JAXA in the coming years. Earlier this year, it was able to snatch pieces of rock from the surface of asteroid Bennu. It is expected to return the sample to Earth in 2023, providing an invaluable comparison to JAXA’s haul on Ryugu.