JAXA's Hayabusa 2 mission plans to pull off a daredevil stunt of touching an asteroid, picking up a sample of the surface and bringing it back to Earth in late 2020. But there's a small hitch in the plans.
On Sunday, JAXA announced it's postponing the touchdown on Ryugu from the end of October until sometime after January 2019.
"As we discovered upon arrival at the asteroid, the surface of Ryugu is covered with numerous boulders with no wide, flat areas," JAXA said.
Hayabusa 2 needs an area free of tall boulders in order to get close enough to the surface to collect a sample. The rocky landscape poses a risk to the spacecraft if a boulder should strike the body or the solar panels.
JAXA found a potential touchdown spot, but it's much tighter than expected.
The spacecraft is rehearsing for its touchdown and testing whether the navigation system can accurately guide it into position to grab a sample in close quarters.
A touchdown rehearsal on Monday went as planned, with the spacecraft capturing an impressive image of its own shadow on the asteroid as it came in close. Hayabusa 2 got within 73 feet (22.3 meters) of Ryugu during the test.
Hayabusa 2 has already deployed two rovers and a lander to investigate Ryugu's surface.
JAXA said it has enough flexibility in Hayabusa 2's mission schedule to accommodate the touchdown delay.
Explore asteroid Ryugu with Japan's Hayabusa 2 spacecraft