Two small spacecraft the size and shape of cheese wheels have made history by sending home pictures of their successful landing on an asteroid.

The probes, collectively named MINERVA-II1, were dropped from Japan's Hayabusa2 spacecraft Friday onto asteroid Ryugu from a height of about 60 meters. Both landed successfully and are transmitting images and data, and at least one is autonomously hopping around the surface as designed.

Though small in stature compared to rovers like NASA's SUV-sized Curiosity on Mars, the MINERVA-II1 probes can move, which classifies them as rovers. They are the first-ever rovers to be deployed on an asteroid.