Japan's Hayabusa2 space probe is descending toward the asteroid Ryugu for an unprecedented touchdown for collecting rock samples inside the asteroid. The landing is scheduled to take place Thursday morning Japan time.
The Hayabusa2 began its descent from its home position altitude of 20,000 meters before 11:00 a.m. on Wednesday, at the speed of 40 centimeters per second.
After about 10 hours, as the probe reached 5,000 meters from Ryugu, the probe slowed its speed to 10 centimeters per second as planned.
It will maintain the speed until it reaches 30 meters from the asteroid's surface, and then attempt a landing at around 10:05 a.m. on Thursday.
The probe made its first touchdown in February. The Japan Aerospace Exploration Agency believes it successfully collected surface rock samples from the asteroid.
This time, Hayabusa2 will try to collect rocks from below the surface, which are believed to be not affected by cosmic rays. Scientists believe such undamaged rocks will shed more light on the origins of life and the formation of the solar system.
In April, prior to the touchdown this time, Hayabusa2 fired a metal object into Ryugu's surface and created a crater. The probe will land near the crater to collect ejected rocks by the impact of the metal object.
JAXA says it is the world's first-ever attempt to probe the inside of an asteroid. But the agency said the mission is a difficult maneuver as the landing site is only about seven meters in diameter.