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NASA’s DART asteroid-smashing spacecraft scores a direct hit

Breathe easy – the mission’s success proves we can defend the Earth from incoming space rocks.

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Published: September 27, 2022 at 2:50 pm

NASA’s DART spacecraft successfully crashed into Dimorphos, its target asteroid, at 00.14 BST on 27 September. The impact shows that the technique could potentially be used to redirect an asteroid or comet on a collision course with the Earth.

The mission, also known as the Double Asteroid Redirection Test, is part of NASA’s planetary defence strategy and is humanity’s first attempt to redirect an asteroid.

The spacecraft was launched on a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California on 23 November 2021 and spent 10 months hurtling through space before crashing into Dimorphos around 11 million kilometres from the Earth.

“DART’s success provides a significant addition to the essential toolbox we must have to protect Earth from a devastating impact by an asteroid,” said Lindley Johnson, NASA’s Planetary Defense Officer.

“This demonstrates we are no longer powerless to prevent this type of natural disaster. Coupled with enhanced capabilities to accelerate finding the remaining hazardous asteroid population by our next Planetary Defense mission, the Near-Earth Object (NEO) Surveyor, a DART successor could provide what we need to save the day.”

DART’s target was the asteroid Dimorphos, a small body just 160m wide in orbit around the larger, 780m-wide asteroid Didymos. Neither asteroid poses a threat to the Earth.

The minutes leading up to the impact were recorded by the spacecraft’s on board camera DRACO, or Didymos Reconnaissance and Asteroid Camera for Optical navigation, and streamed back to Earth. The final images recorded show the fine details of Dimorphos’s craggy surface.

The science team will now use ground-based telescopes around the world, as well as space-based telescopes such as the James Webb Space Telescope, to observe the effect of DART’s impact on the path of the asteroids.

The observations will help researchers to refine the computer models that will be used in any future asteroid-deflecting missions, should the need arise.

“At its core, DART represents an unprecedented success for planetary defence, but it is also a mission of unity with a real benefit for all humanity,” said NASA Administrator Bill Nelson.

“As NASA studies the cosmos and our home planet, we’re also working to protect that home, and this international collaboration turned science fiction into science fact, demonstrating one way to protect Earth.”

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