Run into an asteroid to make it deviate from its trajectory? This is what NASA’s DART spacecraft will attempt to accomplish on Monday. And it’s a Quebecer, Julie Bellerose, who will be in charge.
If all goes according to plan, the spacecraft, launched in November 2021, will crash at more than six kilometers per second, or more than 20,000 km / h, against a small asteroid, millions of kilometers from Earth. .
The Celestial Object targeted poses no threat to Earth. “The DART mission is much more of a precaution, an experiment”, which will make it possible to divert asteroids heading towards Earth, says Julie Bellerose, a native of Sainte-Julie, on the South Shore in the Montreal region. .
The Quebecer has worked since 2013 for the Jet Propulsion Laboratory, a NASA group that lists asteroids in particular. “Right now, the probability of an asteroid hitting us is very low,” she explains in an interview with the To have to. For the next 100 years, even 150 years, it would be very unlikely that there would be such a danger. »
Improbable, but not impossible, because there are still “asteroids or comets that we do not know”, she nuances.
In 2013, an asteroid “had destroyed itself while passing through our atmosphere”. The rare event shook Chelyabinsk Oblast, Russia. “Windows had exploded, there were power cuts, but it was still a relatively small asteroid,” recalls the McGill mechanical engineering graduate.
With its 160 meters in diameter, the asteroid targeted by NASA, named Dimorphos, has a diameter almost ten times larger than that which had grazed the Russian oblast.
Dimorphos is a binary asteroid, that is to say that it orbits around a larger asteroid, called Didymos. “It’s like a very, very small Earth-Moon system,” which makes it easier to observe the results of the experiment with terrestrial telescopes.
Normally, Dimorphos takes about 12 hours to go around Didymos. If the mission is a success, the orbit should “change by about ten minutes”, says Mme Beautiful rose.
A first attempt
At the helm, Julie Bellerose is hopeful that this first attempt by NASA in this area will be a success, even if uncertainty still remains for this type of mission.
Sunday afternoon, the satellite was about “a million kilometers from the asteroid”, she estimated, a few hours before carrying out a last “small corrective maneuver to increase our chances that everything will be fine. »
The autopilot will take over four hours before impact, because the team, which is maneuvering from the east coast of the United States, will no longer have “time to receive the images on Earth and to send the commands to the satellite”, explains Mr.me Beautiful rose.
The James Webb Telescope, along with a small Italian satellite deployed two weeks ago, are expected to take pictures of the scene. But it will not be possible to confirm the success of the mission before mid-October, since it will be necessary to take the time to analyze and observe these changes in trajectory.
“Different nations have wanted to do a test like this in space for ten years,” explains Julie Bellerose, emphasizing the “international effort” that was deployed to carry out the mission.
If DART is a success, the Europeans plan to send another spacecraft in 2024 to orbit Didymos to observe the long-term consequences of the mission. In the event of failure, DART will be able to repeat the experiment in two years.
with Jean-Louis Bordeleau