In 2014, the Japanese Aerospace Exploration Agency (JAXA) launched the Hayabusa 2 spacecraft on a four year journey to Ryugu, an asteroid nearly 200 million miles from Earth. The spacecraft has been in orbit around the asteroid since June and early Friday morning dispatched two rovers to the asteroid's surface.
The confirmation of these rovers' safe landing will mark the first time that a maneuverable robot has landed on the surface of an asteroid.
Photos from the Hayabusa 2 spacecraft taken on September 21, 2018, as robots are dispatched to the asteroid's surface. This photo was taken about 250 feet above the surface. Image: JAXA
The two JAXA rovers, named MINERVA-II1 A and B, navigate using a "hopping" mechanism. Using a more traditional form of locomotion such as wheels or crawlers was impossible because the gravity on Ryugu is so weak. As soon as the rover with wheels started moving, it would've began floating upwards. According to JAXA, when the robots hop, they stay in the air for up to 15 minutes at a time and can move around 40 feet per hop.
The first time a spacecraft landed on the surface of an asteroid was in 2001 when NASA's NEAR mission touched down on Eros. Since then, several missions have been deployed to asteroids and comets, but none of the landers have had the ability to move once they touched down on the surface.
The MINERVA-II rovers are tiny. Image: JAXA
The two robots have a total of seven cameras between them, which they will use to create a stereo image of Ryugu's surface. Later in the mission, Hayabusa 2 will dispatch a third MINERVA-II rover to the asteroid's surface as well as the MASCOT lander developed by Germany and France.