Japan’s Hayabusa 2 spacecraft drops off rovers at an asteroid and takes a shadowy selfie
Japan’s Hayabusa 2 probe takes a picture of the asteroid Ryugu from a distance of about 135 meters (440 feet) with its own shadow seen on the surface. (JAXA Photo)
Japan’s Hayabusa 2 probe began the climactic phase of its mission overnight by sending out its first two rovers as it hovered less than 200 feet over an half-mile-wide asteroid, more than 180 million miles from Earth.
During the drop-off, the 18-foot-wide spacecraft even took a picture of its own shadow, spread out on the asteroid Ryugu’s rocky surface like a black-and-white copy of the Canadian flag.
The release of Hayabusa 2’s MINERVA-II1 rovers occurred at 9:06 p.m. PT Thursday, mission controllers at the Japan Aerospace Exploration Agency reported in a tweet. Hayabusa 2 dipped as low as 55 meters (180 feet) for the release, then retreated from the asteroid.
Hayabusa 2 was launched nearly four years ago and made its rendezvous with Ryugu in June. The goal of the $150 million mission is to study the asteroid in depth, from space and from the surface, and bring samples back to Earth.
This mission follows up on the first Hayabusa odyssey, which touched down on the asteroid Itokawa in 2005 and returned a smattering of samples in 2010. Hayabusa 1 had a similar lander experiment, known as MINERVA (which stands for “Micro Nano Experimental Robot Vehicle for Asteroid”), but the drum-sized rover container missed making its landing and sailed off into interplanetary space instead.
If MINERVA-II1’s container follows its proper course, two 7-inch-wide rovers will be deployed to hop around Ryugu’s surface and take pictures. Stereo images from Rover-1A and Rover-1B would be sent up to the Hayabusa 2 mothership, and then relayed back to Earth.
Ryugu’s gravity is so weak that it could take up to 15 minutes for a rover to make a slow, single hop from one spot to another spot up to 50 feet (15 meters) away.
MINERVA-II1 is just the first surface sortie for Hayabusa 2. An identical lander package, MINERVA-II2, is due to be deployed next year, along with a larger, instrument-laden lander provided by the German and French space agencies and known as MASCOT (“Mobile Asteroid Surface Scout”).
The main spacecraft itself is also due to descend to the surface in 2019 and collect samples for the return trip.