This photo provided by NASA on Oct. 11, 2022, shows the asteroid Dimorphos as seen by the Dart mission spacecraft seconds before impact (NASA/Jons Hopkins APL/Handout)
“It’s not Hollywood” but NASA: the US space agency announced on Tuesday that it managed to deflect an asteroid from its trajectory by projecting a ship the size of a large refrigerator against its surface at the end of September.
An unprecedented test mission, worthy of a science fiction novel, that should allow humanity to learn to protect itself from a possible future threat.
The Dart mission ship had deliberately crashed into the asteroid Dimorphos, which is the satellite of a larger asteroid called Didymos. NASA’s device managed to move it by reducing its orbit in 32 minutes, said the head of the space agency, Bill Nelson, during a press conference.
It is “a watershed moment for planetary defense and a watershed moment for humanity,” he welcomed that his agency’s expectations have been exceeded.
It would already have been “considered a great success if (the spacecraft) had only reduced orbit by about 10 minutes. But it actually reduced orbit by 32 minutes,” he added. With this mission, “NASA has shown that we are serious about defending the planet,” he said.
Dimorphos, located about 11 million kilometers from Earth at the time of impact, is about 160 meters in diameter and poses no danger to our planet.
So far it has circumnavigated Didymos in 11 hours and 55 minutes, a period shortened to 11 hours and 23 minutes, Nelson said.
“It looks like a movie script. But it’s not Hollywood … This mission shows that NASA is trying to be ready for anything the universe can throw at us,” he said.
Images provided by the European Space Agency on September 29, 2022, showing the impact (d) of NASA’s Dart spacecraft with the asteroid Dimorphos, taken by the Webb and Hubble telescopes (ESA/WEBB/Handout)
If the goal has remained relatively modest compared to the disaster scenarios in sci-fi movies like “Armageddon,” this unprecedented “planetary defense” mission, called Dart, is the first to test such a technique. . It allows NASA to train in case an asteroid threatens to hit Earth one day.
“In the future, if we find that an asteroid threatens to hit Earth and is large enough to cause damage, it will be a relief to have done this successful test,” Bill Nelson told Reuters.AFP.
– Egg shape –
To establish how much the asteroid’s trajectory has been altered, the scientists analyzed data from ground-based telescopes in Chile, South Africa and the United States.
Description of NASA’s DART missile probe, which crashed into a small asteroid to alter its trajectory, a test to anticipate a possible future collision between Earth and an asteroid (AFP/)
The latter observed the variation in brightness when the small asteroid passes in front of and behind the large one.
Shortly after the collision, the first images, taken by ground-based telescopes and the nanosatellite aboard the LICIACube mission, showed a large cloud of dust around Dimorphos, stretching for thousands of kilometers.
Then the James Webb and Hubble telescopes, the most powerful space observatories, revealed detailed views of the impact of the NASA spacecraft, showing in particular the movement of the ejecta, the material ripped from the star.
All of this should allow a better understanding of the composition of Dimorphos, representative of a population of fairly common asteroids, and therefore measure the exact effect that this technique, called kinetic impact, can have on them.
Images of Dimorphos, taken shortly before impact, show that its surface is gray, rocky, and egg-shaped.
The mission revealed that the asteroid looked more like an amalgamation of large rocks held together by their mutual gravity than a solid mass.
The kamikaze ship had traveled for ten months since its takeoff in California.
Image provided by NASA on October 11, 2022, showing the latest full image of asteroid Dimorphos (NASA/Jons Hopkins APL/Handout)
Nearly 30,000 asteroids of all sizes have been cataloged in the vicinity of Earth.
Today, none of these known asteroids threaten our planet for the next 100 years. Except they’re not all identified yet.
Those of a kilometer or more have been sighted almost all, according to scientists. But they estimate that they only know about 40% of the asteroids that measure 140 meters or more, those capable of devastating an entire region.
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