Asteroid Bennu is a spherical carbon object, the study of which is being carried out by the OSIRIS-REx probe. It is planned that the probe will collect soil from the asteroid, make a map of its surface and return to Earth by 2023.
Now OSIRIS-REx in the framework of the Detailed Survey is engaged in a complete study of the asteroid. During the mission, the probe is engaged in the construction of an accurate Bennu model, the creation of detailed color and panchromatic surface maps, as well as the choice of a place for further landing on an asteroid.
For the first time, the device recorded space explosions on the surface of Bennu almost a year ago – in January 2019. The event was accompanied by the release into space of about 400 particles ranging in size from several centimeters to several tens of centimeters.
Observations of particles during the following similar events showed that some of them moved at a speed of about 3.3 m / s, while others did not accelerate enough to overcome the gravity of the asteroid. Thus, slow particles, including rather large ones, remained in the close orbit of the asteroid, becoming a kind of satellite.
In total, OSIRIS-REx managed to record three space explosions, each of which occurred in different places. The probable cause of these events, astronomers call the asteroid bombing micrometeorites. On the other hand, space rock explosions can be the result of a rupture of minerals containing water – they can be destroyed due to the displacement of water molecules, which is caused by a sharp temperature drop.