NASA’s idea of saving planet Earth from an asteroid impact by crashing an uncrewed spacecraft into it is being put to test on Monday.
Dubbed the Double Asteroid Redirection Test (DART), this will be the world’s first planetary defense test mission.
According to the agency, a spacecraft is set to impact the small moonlet asteroid Dimorphos, which orbits a larger companion asteroid called Didymos, at 23:14 UTC, with the aim of changing its orbit.
There will be a live-feed of the event, which you can watch here:
The DART spacecraft launched in November 2021, aboard a SpaceX Falcon 9 rocket from Vandenberg Air Force Base, California. After over a year of cruise, it is set to intercept Didymos’ moonlet, at a time when the Didymos system is within 11 million kilometers of Earth. This will enable observations by ground-based telescopes and planetary radar to measure the change in momentum imparted to the moonlet.
DART will collide with the moonlet at a speed of approximately 6.6 km/s, with the aid of an onboard camera (named DRACO) and sophisticated autonomous navigation software.
The collision is expected to change the speed of the moonlet in its orbit around the main body by a fraction of one percent, but this will change the orbital period of the moonlet by several minutes – enough to be observed and measured using telescopes on Earth.
As explained by Lindley Johnson, NASA’s Planetary Defense Officer, DART will be the first demonstration of the ‘kinetic impactor’ technique in which a spacecraft deliberately collides with a known asteroid at high speed to change the asteroid’s motion in space. This technique is thought to be the most technologically mature approach for mitigating a potentially hazardous asteroid.
