Japan's Hayabusa2 space probe has been slowly descending to the asteroid Ryugu in its final maneuver to land on the asteroid to bring its rock samples back to Earth.
The descent began at around 1:15 PM, Japan time, or 04:15 UTC on Thursday from an altitude of 20,000 meters.
About six hours after the start of the descent, the probe was descending at a reduced speed of 360 meters per hour. Initially, it was at 3,000 meters an hour.
Officials at the Japan Aerospace Exploration Agency, or JAXA, said they have seen no problems and will continue with the maneuver.
If all goes as scheduled, it will land on Ryugu at around 8 AM on Friday, Japan time, or 23:00 UTC on Thursday.
About two hours before the landing, the craft is slated to reach an altitude of about 500 meters above Ryugu. It will then be switched to autonomous landing mode.
Hayabusa2 has a one-meter-long rock collecting device extending from its bottom. The tip of the device will come in contact with the asteroid's surface for a few seconds in the landing.
Then the probe will promptly fire bullets toward the surface to break rocks and stir up resulting particles, which it will gather up.
The Hayabusa2's descent began five hours later than originally scheduled due to some irregularities in the initial settings.
JAXA officials said they have made up for the delay by increasing the craft's descending speed.
Hayabusa2 is aiming for a six-meter-wide touchdown zone in what JAXA described as a challenging mission. Controllers say they will not hesitate to cease its descent once something unusual happens.