A new set of research papers published by the team responsible for the OSIRIS-REx spacecraft has revealed that the asteroid is losing material constantly. The active surface of the asteroid has revealed that asteroids can be more active than previously thought, as the lost material can offer interesting information.
The report offers a wealth of interesting details related to the nature of the particles released by Bennu as well as the methods which are used to observe the phenomena. One of the scientists involved in the Bennu mission observed the loss by accident.
The researchers made the discovery while long at images which are taken by a specialized camera aboard OSIRIS-Rex, a spacecraft that was sent to the Bennu with the aim to learn more about it. Images recorded by the camera are used to calculate the trajectory of the spacecraft and make necessary corrections.
At first sight, the researchers thought that he was looking at an unusual star cluster, but further analysis revealed that what he saw was a fine cloud of particles that came from the surface of the asteroid. This theory was confirmed by additional research.
Since OSIRIS-REx is looking at Bennu, more than 300 particle ejections have been observed. Some of the particles will travel through pace while others reach the orbit of the asteroid, and most of them tend to return to the surface. There is no risk for the spacecraft since the particles are small.
A number of possible events that could generate the ejections were taken into account, including the presence of water vapors, small meteorite impacts and thermal stress, with the last two having the highest chances and proving that Bennu is quite active. Further research is needed to track down the exact source.
More information about Bennu could be shared in the future, and the papers have been published in scientific journals.