Japan to make crater on asteroid to get samples from inside

Japan's space agency said Monday that its Hayabusa2 spacecraft will follow up last month's touchdown on a distant asteroid with another risky mission to drop an explosive to make a crater and collect underground samples to get possible clues to the origin of the solar system.

Hayabusa2 made history on Feb. 22 when it successfully touched down on the boulder-rich asteroid, where it also collected some surface fragments.

The Japan Aerospace Exploration Agency said Hayabusa2 is to drop a copper impactor the size of a baseball and weighing 2 kilograms on the asteroid on April 5 to collect samples from deeper underground where they had not been exposed to the sun or space rays.

The new mission will require an immediate evacuation of the spacecraft to the other side of the asteroid so it won't get hit by flying shards from the blast, JAXA said. While moving away, Hayabusa2 will leave a camera to capture the outcome.

The mission will allow JAXA scientists to analyze details of a crater to find out the history of the asteroid, said Koji Wada, who is in charge of the project.

Hayabusa2 will start descending toward the asteroid the day before to carry out the mission from its home position of 20 kilometers above.

It will drop a cone-shaped piece of equipment containing explosives that will blast off a copper plate on the bottom. It will turn into a ball and slam into the asteroid at the speed of 2 kilometers (1.2 miles) per second.

JAXA has previously planned to have Hayabusa2 briefly touchdown in a crater, but an agency researcher, Takashi Kubota, said they may not force it to prioritize safety for the spacecraft. Kubota said it would be the first time a spacecraft would take materials from underground a space object.

The asteroid, named Ryugu after an undersea palace in a Japanese folktale, is about 900 meters (3,000 feet) in diameter and about 300 million kilometers (180 million miles) from Earth.