Why Is NASA Targetting Asteroids Through Its Spacecraft DART?

NASA's Double Asteroid Redirection Test (DART) successfully crashed into asteroid Dimorphos on Monday. This is the space agency's first attempt to move an asteroid in space.

IMPACT SUCCESS! Watch from #DARTMIssion's DRACO Camera, as the vending machine-sized spacecraft successfully collides with asteroid Dimorphos, which is the size of a football stadium and poses no threat to Earth. pic.twitter.com/7bXipPkjWD

— NASA (@NASA) September 26, 2022

"After 10 months flying in space, NASA's Double Asteroid Redirection Test (DART) – the world's first planetary defense technology demonstration – successfully impacted its asteroid target on Monday," NASA said. The success of the controlled impact was announced by the Mission control at the Johns Hopkins Applied Physics Laboratory (APL) in Maryland on Monday 7:14 p.m (GMT-4)

Here is all you need to know about NASA's DART mission:

Why was the asteroid hit?

In a first, planetary defense technology was demonstrated by the space agency. The impact was designed to demonstrate Earth's defense in case an earth-bound celestial body ever threatens the planet with a collision.

NASA said the DART's impact with the asteroid Dimorphos "demonstrates a viable mitigation technique for protecting the planet from an Earth-bound asteroid or comet, if one were discovered."

"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. He said that NASA's international collaboration on DART mission "turned science fiction into science fact".

What is asteroid Dimorphos?

Dimorphos is an asteroid moonlet and was discovered in 2003. It has a diameter of 530 feet and revolves around a bigger asteroid Didymos-- 2,560-foot in diameter.

The space agency said that neither Dimorphos nor Didymos pose any threat to Earth. However, the demonstration confirmed that any future threats to Earth in the form of an asteroid can be deflected using a spacecraft with the technique called kinetic impact, NASA said.

How did the DART work?

The DART weighs 570kg and traveled a distance of 56,000 miles and crashed into Dimorphos with a speed of 14,000 miles per hour, slightly slower than the asteroid's orbit speed. NASA said the final images before the impact "revealed the surface of Dimorphos in close-up detail".

The DART spacecraft consists of a Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO) and Small-body Maneuvering Autonomous Real Time Navigation (SMART Nav) algorithms. The two systems helped the DART to identify the smaller body to complete the experiment.

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

He said that this has shown that planet Earth is 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," Johnson said.

Armed with a dozen telescopes, a global team is now closely monitoring the asteroid system within 7 million miles of Earth. They will monitor how precisely did the DART deflect the asteroid. "In the coming weeks, they will characterize the ejecta produced and precisely measure Dimorphos' orbital change to determine how effectively DART deflected the asteroid," the NASA said.

The team will now observe Dimorphos with ground-based telescopes to see how the DART's altered the asteroid's orbit. "Researchers expect the impact to shorten Dimorphos' orbit by about 1%, or roughly 10 minutes," NASA said.