All the lights are green for the Dart probe which is currently heading towards the asteroid Didymos and its moon Dimorphos. This unprecedented mission aims to demonstrate that it is possible to deflect an asteroid from its trajectory by an impact. See you on September 27 to follow the operation live!
Launched in November 2021, the probe dartdart NASA prepares to crash into asteroid binarybinary composed of Didymos and his moonmoon Dimorphos, on the night of September 26 to 27, 2021. Dart’s objective is to hit Dimorphos at 6 km/s, in order to slightly modify its trajectory around Didymos, for planetary defense purposes. We will have the opportunity to talk about it in more detail in a few days with Patrick Michel, CNRS research director at the Côte d’Azur Observatory, scientific manager of Hera and coordinator of the Aida cooperation (Dart + Hera).
In the meantime, NASA has just made public a “composite image” of the light from the binary asteroid Didymos, then located some 20 million kilometers from the probe. This image was acquired by the Draco camera on July 27. This first series of 243 images has no scientific interest. It is simply used to locate Didymos in order to make necessary adjustments before the mission team begins using the images to guide the spacecraft to the asteroid autonomously.
An unprecedented mission to deflect an asteroid
If, for the moment, the probe is piloted from the ground, it will become autonomous, that is to say without human intervention, a few hours before its impact against Dimorphos. Hence the need to ensure the proper functioning of this camera which will be used to guide the probe towards its objective.
Using observations taken every five hours, the Dart team will execute three course correction maneuvers over the next three weeks, each of which further reduces the margin of error for the required course of spacecraft until impact.
After the last maneuver, on September 25, about 24 hours before impact, the navigation team will know the position of the Dimorphos target to within 2 kilometers. From there, the Dart probe will be alone to guide itself autonomously until its collision with the asteroid. The objective of the mission is to slightly modify the trajectory of Dimorphos around Didymos in order to assess our ability to deviate the trajectory of a small body by an impact, an important step in demonstrating that it is possible to protect the Earth from an asteroid using the technique ofimpactorimpactor kinetic.