A robotic probe the size of a shoebox set itself down on the asteroid Ryugu, more than 180 million miles from Earth, and conducted a 17-hour survey of its rocky surroundings.
The foot-wide, German-built lander is called MASCOT, which stands for Mobile Asteroid Surface Scout. It was ejected from Japan’s Hayabusa 2 probe from a height of 51 meters (167 feet) and drifted downward to Ryugu at walking speed.
“It could not have gone better,” Tra-Mi Ho, MASCOT project manager at the DLR Institute of Space Systems, said today in a status update. “From the lander’s telemetry, we were able to see that it separated from the mothercraft and made contact with the asteroid surface approximately 20 minutes later.”
MASCOT took a picture of its own shadow on Ryugu’s surface as it descended:
Hello #Earth, hello @haya2kun! I promised to send you some pictures of #Ryugu so here’s a shot I took during my descent. Can you spot my shadow? #AsteroidLanding pic.twitter.com/dmcilFl5ms
— MASCOT Lander (@MASCOT2018) October 3, 2018
The lander is equipped with a swing arm to move itself around the surface. It had to use the arm to relocate itself and get oriented properly to collect scientific data, mission managers said in a tweet.
MASCOT’s lifetime was limited because it’s powered by onboard lithium batteries. It was expected to have only 16 hours to record observations with its four instruments — a camera, a radiometer, a magnetometer and a French-built infrared spectrometer — and upload the data to Hayabusa 2 before its batteries died.
It turned out that the lander exceeded expectations by operating for more than an hour longer than expected:
All done with work! Oh my… can that be right? I explored Ryugu for more than 17 hours. That is more than my team expected. Do I get paid overtime for this? #asteroidlanding
— MASCOT Lander (@MASCOT2018) October 4, 2018
And during this extra time, I also made another hop and explored part of a third asteroid day! But the best thing is: I sent ALL the data I collected to @haya2kun! Now team, it's up to YOU to understand Ryugu. #AsteroidLanding
— MASCOT Lander (@MASCOT2018) October 4, 2018
Hayabusa 2 will relay the data to Earth over the next few days.
MASCOT’s mission came almost two weeks after Hayabusa 2 deployed two mini-rovers to Ryugu’s surface for an initial round of reconnaissance. In the coming months, Hayabusa 2 will descend to the asteroid and blast bits of rock from the surface for collection. It also has another mini-rover to release.
The probe is scheduled to start the return journey to Earth next year and drop off its samples during a flyby in late 2020.
This is an updated version of a report first published at 9:33 p.m. PT Oct. 3.
