• Tonight, at 1:14 a.m. French time, a NASA space probe will deliberately hit an asteroid 160 m in diameter in order to deflect it from its trajectory.

  • This mission, dubbed DART, should make it possible to test defense capabilities in the event of a possible asteroid impact with the Earth.

  • French researchers are taking part in this mission and will work in the years to come to exploit the data concerning the impact and its consequences on the asteroid.

Tonight, at 1:14 a.m. French time, a NASA probe will crash into the asteroid Dimorphos, 11 million kilometers above the ground.

We are not in a remake of


and Bruce Willis will not be responsible for going to drill a well on this celestial object 160 meters in diameter to deposit a nuclear charge there.

But the purpose will be the same as the apprentice astronauts of the successful film: to deviate the trajectory of the asteroid to prevent it from colliding with the Earth.

Or rather a dress rehearsal of what space agencies could deploy if such a threat were to emerge.

Because today, Dimorphos, which orbits around a larger asteroid called Didymos, does not represent any danger for earthlings.

Just like the other 27,500 listed today.

Astronomers estimate, however, that there are thousands of near-Earth asteroids that we don't know exist and that could collide with our planet or pass nearby.

Like the one that exploded on February 15, 2013, east of the Urals, in Chelyabinsk, Russia.

That day, a 19-meter asteroid exploded in the sky causing a shock wave that injured nearly 1,500 people.

Tonight, @NASA intentionally crashes their #DART spacecraft into a 160m asteroid, to nudge its orbit in a world-first test of #AsteroidDeflection🛰️↩️🪨

And yes, the live feed will be streaming down to watch on #NASATV & #ESAWebTV from midnight CEST!🔴📹👉https://t.co/3gn2kMXoXb pic.twitter.com/mjptlJBIla

— ESA Operations (@esaoperations) September 26, 2022

Access to this content has been blocked to respect your choice of consent

By clicking on "


", you accept the deposit of cookies by external services and will thus have access to the content of our partners


And to better remunerate 20 Minutes, do not hesitate to accept all cookies, even for one day only, via our "I accept for today" button in the banner below.

More information on the Cookie Management Policy page.

“The very large asteroids present in the solar system, we know them, they are easy to observe because they are brilliant in space, they reflect sunlight, explains Naomi Murdoch, researcher in planetology at Isae- Supaero, part of this mission called DART (for Double asteroid redirection test).

And the bigger they are, the more sunlight they reflect, the easier they are to see.

The smaller they are, the harder it is to detect them.

It is currently estimated that 40% of asteroids the size of Dimorphos are known.

One day we could discover one that will collide with the Earth.


Launched in November 2021, this spacecraft, lighter than a small car, will therefore hit its target tonight at a speed of 24,000 km / h.

Until the last moment, he will film the asteroid to find out what it looks like up close.

Images transmitted with a lag of 45 seconds, until its impact with the celestial object.

Defending the Earth requires detecting asteroids

It is then the LICIACube, a small satellite the size of a toaster located 55 km away, which will observe the consequences of the impact, in particular the ejected fragments of rock and regolith, this dust which covers its surface.

The Hubble and James-Webb space telescopes will also be pointed at Dimorphos, like many others from the ground.

Just to see if the deviation of trajectory has indeed taken place, thanks to the variations of the brightness when Dimorphos will pass in front of Didymos.

Today, Dimorphos takes 11 hours and 55 minutes to circumnavigate Didymos.

After the DART impact, it should take ten minutes less.

“Which makes a change in speed of a few centimeters per second, but even this minimal time is what we would need if there was a real danger for the Earth”, assures Naomi Murdoch.

If this scientist will look closely at the first images to learn more about the asteroid, a large part of her work will consist of exploiting the data transmitted from 2026 by the European probe Hera.

It must take off within two years, direction Dimorphos "to return to the scene of the crime", jokes the planetary scientist.

Thanks to its onboard camera, its laser or its infrared scanner, we will learn more about the precise shape of the asteroid, the crater left by DART or its thermal properties.

“We will also try to land on the surface with a small CubSat.

All of this will allow us to demonstrate that we have a well-mastered method of planetary defense,” continues the co-investigator of the Hera mission at Isae-Supaero.

“The whole point of the mission is to demonstrate how to build the probe, how to launch it, how to destroy the target and how to deflect the asteroid in space.

Of course, the method employed when danger arises will depend on how much time we have before impact.

That's why planetary defense isn't just trying to deflect an object in space.

It also means detecting it, which is why every night astronomers look at those who could pose a problem for us.

Then, it is to assess this danger and see when it could cross the Earth's orbit.

And it's preventing and mitigating the possible effects, ”concludes the planetary scientist who will stay up all night to see the first images of a project she has been working on for fifteen years.


James Webb: These new images of the Orion Nebula, "like in 3D"


Perseverance: NASA's rover has detected potential biosignatures on Mars

  • Space

  • Science

  • Asteroid

  • Earth

  • Nasa

  • ESA

  • Astronomy