NASA’s DART Mission Hits Asteroid in First-Ever Planetary Defense Test

After 10 months in space, NASA’s Double Asteroid Redirection Test (DART) – the world’s first planetary defense technology demonstration – is successful and ready to repell asteroids. DART successfully impacted its asteroid target on Monday, the agency's first attempt to move an asteroid in space.

Mission control at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, announced the successful impact at 7:14 p.m. EDT.

Astrophysicist Dr. Jim Green of NASA’s Planetary Science Division said that as part of the organization's overall planetary defense strategy, the DART rocket could split an incoming asteroid or comet into smaller pieces to protect Earth from a catastrophic impact similar to what is believed to have led to dinosaur extinction.

“At its core, DART represents an unprecedented success for planetary defense, 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.”

DART targeted the small moonlet of Didymos, Dimorphos and orbits a larger asteroid. It poses no threat to Earth.

NASA was able to successfully deflect an asteroid by crashing a spaceship into it. This mission one-way trip confirms that we have the ability to deliberately impact asteroids in order contains them on their course and prevent them from crashing into human habitats.

The investigation team will now observe Dimorphos using ground-based telescopes to confirm that DART’s impact altered the asteroid’s orbit around Didymos. Researchers expect the impact to shorten Dimorphos’ orbit by about 1%, or roughly 10 minutes; precisely measuring how much the asteroid was deflected is one of the primary purposes of the full-scale test.

“Planetary Defense is a globally unifying effort that affects everyone living on Earth,” said Thomas Zurbuchen, Associate Administrator for the Science Mission Directorate at NASA Headquarters in Washington. “Now we know we can aim a spacecraft with the precision needed to hit a small space object. A change in speed of just a few meters per second will make all the difference to the path an asteroid takes.”

The spacecraft includes a sole instrument, the Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO), which is enhanced with a sophisticated guidance, navigation and control system that works in tandem with Small-body Maneuvering Autonomous Real Time Navigation (SMART Nav) algorithms, enabled DART to identify and distinguish between the two asteroids, targeting the smaller body.

These analytical systems guided the 1,260-pound (570-kilogram) box-shaped spacecraft through the final 56,000 miles (90,000 kilometers) of space into Dimorphos, intentionally crashing into it at roughly 14,000 miles (22,530 kilometers) per hour to slightly slow. The final images obtained by the spacecraft seconds before impact revealed the surface of Dimorphos in close-up detail.

A while ago, a satellite was launched and approached an asteroid. About 15 days before it reached it, the spacecraft’s companion CubeSat detached to take pictures of the impact as well as of any changes which might happen after. Alongside images from DRACO, the new images from LICIACube show the impact of asteroid collisions to help scientists keep track of their effectiveness. A new cube satellite to measure the intensity of radiation in deep space has launched and will send images back to Earth one by one.

"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 possible danger." The Near-Earth Object Surveyor would enable the NEODART project to find hazardous asteroids faster and therefore, save humanity from extinction.

When the asteroid pair passes closer to Earth than before, a global team of researchers will use ground-based and space-based telescopes to research it. Over the coming weeks, they will characterise the ejecta produced and measure Dimorphos’s change in orbit to figure out how much it was deflected back on course. The research will help us validate and improve the scientific models that are useful for predicting how effective this technique is in deflecting asteroids.

"This first-of-its-kind mission required incredible preparation and precision, and the team exceeded expectations on all counts," said APL Director Ralph Semmel. "Beyond the truly exciting success of the technology demonstration, capabilities based on DART could one day be used to change the course of an asteroid to protect our planet.

Roughly four years from now, the European Space Agency’s Hera project will survey both Dimorphos and Didymos. The project team will have a particular focus on measuring the crater left by DART's collision as well as conducting a precise mass measurement of Dimorphos.