NASA scientists are gearing up for the world's first mission testing planetary defense — and they want you to watch.
The space agency's Double Asteroid Redirection Test (DART) will test technology to defend Earth against future asteroids and comets by deliberately crashing into an asteroid — which poses no threat to Earth — at some 15,000 mph. The target, a larger asteroid's moonlet named Dimorphos, measures about 525 feet wide.
The goal of the test is to prove that a spacecraft can autonomously navigate to a specific asteroid and purposely crash into it, disintegrating on impact and changing the object's speed and path. Scientists aim to measure that change using telescopes on Earth.
The mission doesn't quite mirror a sci-fi disaster movie like "Armageddon," since it aims to deflect the asteroid rather than destroy it completely.
NASA plans to live stream the entire event on September 26, and it's inviting the public to tune in on its website, Facebook, Twitter, or YouTube. A live briefing will take place at 6 p.m. ET on "Impact Day" from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, which builds and manages the DART spacecraft.
Researchers expect the kinetic impact to take place at 7:14 p.m. ET. The space agency is also hosting an in-person event to mark the momentous occasion.
Dimorphos and Didymos to scale with familiar structures on Earth.
Johns Hopkins University/APL
Scientists launched the small, $330 million probe last fall, sending it to travel nearly seven million miles away from Earth. It's carrying another small spacecraft called LICIACube, which will be released from DART 10 days before impact in an attempt to photograph the collision and resulting debris.
Astronomers currently estimate there are about 25,000 near-Earth asteroids that are 500 feet or larger in size. DART will hopefully provide critical data to aid researchers in preparing for a future asteroid that could have a catastrophic impact on our planet — if they happen to discover one.