Japan's national space agency says its probe, "Hayabusa2", has less than a week to go before reaching the orbit of the asteroid Ryugu.
Mission manager Makoto Yoshikawa of the Japan Aerospace Exploration Agency, or JAXA, said on Thursday that course control has been done as planned, and all has gone well. He added that his team is ready to carefully carry out its remaining work.
The probe was launched in late 2014 to travel to the asteroid 300 million kilometers from Earth and shed light on the origin and evolution of the solar system as well as life.
JAXA says the Hayabusa2 is 70 kilometers from Ryugu, and expected to enter its orbit as soon as next Wednesday.
Yoshikawa said the agency's operators will readjust the probe's course 4 more times.
JAXA also released images taken by the probe on Wednesday. They show that the 900-meter-diameter asteroid is pointed at its poles and has what looks like a mountain range near its equator. Yoshikawa compared Ryugu's shape to a spinning top or an abacus bead.
A dent that looks like a crater and what looks like a huge rock can also be seen. The dent is about 200 meters in diameter. Yoshikawa said the crater near the equator may be a good landing point for the probe.
After reaching the orbit, the probe is to take more photos of Ryugu and carry out detailed observations.
Starting in September, JAXA plans to try to land the probe on the asteroid to collect surface samples.