Japan's space agency is preparing to land the Hayabusa2 probe on an asteroid.
The probe will begin to descend from an altitude of 20,000 meters shortly after 8 AM Japan time on Thursday, or 23:00 UTC on Wednesday. The landing is scheduled for about 24 hours later, and scientists will later attempt to collect rock samples.
Hayabusa2 was launched in 2014 and arrived above asteroid Ryugu in June of last year. The asteroid is about 300 million kilometers from Earth.
The Japan Aerospace Exploration Agency, or JAXA, planned a landing last October, but postponed it because the surface of the asteroid was rockier than expected.
The agency found a flat area near the equator of the asteroid that is free of rocks larger than 60 centimeters. The scientists are aiming the probe at an extremely small landing area 6 meters in diameter.
JAXA researchers say they will carefully carry out the operation, and that they may abort it in case of an abnormality.