Japan's space agency JAXA says its Hayabusa2 probe has released its first pair of rovers designed to land on the asteroid Ryugu.
JAXA officials say they'll likely know on Saturday, Japan time, whether the MINERVA-II-1 rovers have successfully landed on the asteroid, through images beamed back to Earth.
They say the robotic vehicles were released shortly after noon on Friday, when the Hayabusa2 descended from an altitude of 20,000 meters to 55 meters from the asteroid's surface.
The round rovers are 18 centimeters wide and 7 centimeters high.
They're designed to hop on Ryugu's surface, as the asteroid's weak gravity makes moving on wheels difficult. Ryugu is 900 meters in diameter.
The landing is aimed at testing the rovers' propulsion method and taking pictures of the asteroid's surface to use for the planned landing of the probe in late October.
The Hayabusa2 is carrying two more robotic vehicles.
Its predecessor, Hayabusa, failed to land a rover on the asteroid Itokawa in 2005.