Picture of the month

Rocky surface

This slightly blurry distorted image of a rocky surface is more interesting than it might first appear. The small instrument responsible for the picture is the first of several robot “hoppers” to be deployed to an asteroid called Ryugu by the Japanese probe Hayabusa2, before the spacecraft itself will land on the asteroid surface to take samples back to Earth. The asteroid consists mainly of nickel, iron, cobalt, water, nitrogen, hydrogen and ammonia. It’s slightly less than 1 km in diameter and weighs 450 million tonnes. The image was taken as the robot, which is about the size of a shoebox, jumped several metres high – a journey that, owing to a gravitational acceleration of just 0.0001 m s–2, takes about 15 minutes.