See the close contact with the asteroid

On February 21 last year, the Japanese probe Hayabusa2 rubbed the asteroid Ryugu. It took some rock samples and left the surface just as quickly again. Now the space probe is on its way back to Earth with the load full of space stones.

In connection with the close meeting, Hayabusa2 took the opportunity to take many pictures of the asteroid's surface. Analyzes of the images now reveal that the asteroid has been astray in the solar system.

- It seems that for a period the asteroid has been much closer to the sun than it is today and it is very interesting. We would like to keep track of how these types of asteroids move because there is a collision risk with the earth, says Sanna Alwmark, a planetary geologist at Lund University.  

On the surface of the asteroid there are areas that are darker and a little red in color. The Japanese scientists who have analyzed the images interpret it as if the stones have been subjected to so-called thermal metamorphosis for a short time. This means that the minerals have been exposed to strong heat, the researchers write in a study published in this week's Science.

During the actual sampling on the surface of the asteroid, the rocket engine raised stones of this red type, and so it is hoped that there are copies of them in the stone collection that are now on the way to Earth with Hayabusa2. The estimated time of arrival is the end of 2020.