Japan’s Hayabusa 2 spacecraft nearly back home with precious cargo onboard – samples from asteroid Ryugu that it collected a year ago will land on Earth on December 6.
The spacecraft is set land in the Australian outback with a container of soil samples and data that could provide clues to the early days of our Solar System.
“Organic materials are origins of life on Earth, but we still don’t know where they came from,” said Makoto Yoshikawa, Hayabusa 2 project mission manager, at a press briefing. “We are hoping to find clues to the origin of life on Earth by analyzing details of the organic materials brought back by Hayabusa 2.”
JAXA, the Japanese space agency, said the capsule containing the samples should land in the Woomera Prohibited Area in Australia, a restricted military test site about 122,000 square kilometers in size, located approximately 450 km northwest of Adelaide.
On November 25, the Hayabusa 2 team received permission from Australia to transition to the re-entry orbit. They conducted a trajectory correction maneuver on November 26 to put the spacecraft into the correct entry corridor.
The spacecraft will drop the capsule containing the samples from a distance of about 220,000 km from Earth. The capsule is quite small, only about 40 cm in diameter. A heat shield will protect the capsule during its fiery plunge through our atmosphere. When the capsule reaches an altitude of about six miles above the ground, a parachute will open to allow for a hopeful soft landing.
A beacon will activate to transmit the location of the capsule, and multiple receivers have been set up around the target area to retrieve those signals. Radar, drones, and helicopters will be at the ready to assist in the search and retrieval.
Without those measures, a search for the small capsule “would be an extremely difficult,” Yoshikawa said.
Hayabusa 2 launched in December 2014, and arrived at Ryugu in mid-2018. A German-built MASCOT lander collected samples from Ryugu in February and July 2019, storing each sample in separate chambers. The mission team said they believe at least 300 milligrams of material was collected, and likely more.
For the Hayabusa 2 spacecraft, it’s not the end of the mission. After dropping the capsule, it will head to another distant small asteroid called 1998KY26, with the journey slated to take 10 years.
Scientists will compare the chemical composition of the samples with Earth and Moon rocks, seeking to understand factors about Earth’s origin, such as whether asteroids played a role in bringing water to Earth.