La sonde DART qui va s’entraîner à dévier un astéroïde a ouvert son « œil »


The DART mission, which will train to deflect an asteroid by crashing into it, has taken its very first photos. Important images, because they prove that the on-board camera did not suffer from take-off.

Violent vibrations, extreme temperature change. The launch of a space mission often puts a strain on the precision instruments on board. The team that oversees DART, the mission in charge of training to deflect an asteroid, was therefore anxious to know if the on-board camera was still functional. ” The machine’s telescopic instrument components are sensitive to movements as small as 5 millionths of a meter. A very small displacement of an element of the instrument could pose serious problems “, Explains NASA on its site.

The team of DART (Double Asteroid Redirection Test) has received good news, however, we learn from US space agency publication December 22: a few weeks after its launch from the Vandenberg base in California, the probe opened its eyes and took its very first photos.

The DART probe took its first photos

In the first image, taken on December 7, a dozen stars can be seen near the area of ​​intersection of the constellation Perseus, the constellation Pisces, and the constellation Taurus. This photo was taken 3.2 million kilometers from Earth, or 11 light seconds.

The DART probe which will train to deflect an asteroid has opened its
DART’s first photo Source: NASA / Johns Hopkins APL

The team in charge of overseeing the navigation of the DART mission used the stars in this photo to determine how the telescopic camera (dubbed DRACO) was oriented in relation to the spacecraft. ” Thanks to these elements, the DART team was able to precisely move the probe in order to point DRACO at interesting objects, such as the M38 cluster. “.

In a second photo, taken on December 10, the DART mission was able to immortalize the stars of this cluster, located 4,200 light years from us. ” Purposely capturing images like this, with lots of stars, helps the team spot optical imperfections and accurately assess the brightness of objects. All of this data is important to ensure that DRACO is running accurately., when it begins to photograph the destination of the spacecraft, the Didymos binary system », Specifies NASA.

The DART probe which will train to deflect an asteroid has opened its
The 2nd photo of the DART mission // Source: NASA / Johns Hopkins APL

The last images DART will take should be pretty impressive. To train to deflect an asteroid, this mission will indeed use great means and … crash into it.

The DART probe will crash on the asteroid Dimorphos

The DART spacecraft weighs 550 kilograms and is directed towards an asteroid called Dimorphos which itself orbits an asteroid called Didymos. If all goes according to plan, the probe will crash into it in the fall of 2022. The objective is to modify the orbit of the moon of Didymos in this way.

Dimorphos does not threaten Earth in any way. But she is an ideal candidate for training to deflect an asteroid that would pose a risk, as the moon of Didymos is around 160 meters, ” which is typical of the size of the asteroids which could pose the greatest threat to Earth “. Furthermore ” scientists can measure Dimorphos’ orbit change with ground-based telescopes », Explains NASA.

This should make it easier to spot the deviation caused by DART on Dimorphos. This deviation will indeed be tiny. If one aimed at a non-binary asteroid the size of Didymos, it might take years to perceive it. Aiming at the moon of this asteroidal system should make it possible to assess the deviation more quickly, by observing the orbit of Dimorphos around Didymos.



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