NASA’s DART Mission
After 10 months long flying in space, NASA’s Double Asteroid Redirection Test (DART) mission- the world’s first planetary defense technology demonstration has successfully impacted its asteroid target on 27 September, 2022, the NASA’s first attempt to move an asteroid in space.
Double Asteroid Redirection Test, DART’S impact with the asteroid Dimorphos demonstrates a viable mitigation technique for protecting the planet from an Earth-bound asteroid.
NAS’s Administrator Bill Nelson said “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. 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 mission targeted the asteroid moonlet Dimorphos, a small body just 530 feet (160 meters) in diameter. It orbits a larger asteroid, 2,560-foot (780-meter) called Didymos. However, none of these asteroids pose a threat to Earth.
The mission’s one-way trip confirmed that NASA can successfully navigate a spacecraft to intentionally collide with an asteroid to deflect it. This technique is known as kinetic impact.
Planetary Defense Test
“Planetary Defense is a globally unifying effort that affects everyone living on Earth. Now we know we can aim a spacecraft with the precision needed to impact even a small body in space. Just a small change in its speed is all we need to make a significant difference in the path an asteroid travels.” said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington.
DRACO & SMART Nav
The spacecraft’s sole instrument, the Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO), together with a guidance, navigation and control system that works in tandem with Small-body Maneuvering Autonomous Real Time Navigation (SMART Nav) algorithms which enabled DART to identify and distinguish between the two asteroids, targeting the smaller body. DRACO’s final images, obtained by the spacecraft seconds before impact, revealed the surface of Dimorphos in detail.
Over the coming weeks, NASA will characterize the ejecta produced and measure Dimorphos’ orbital change to determine how effectively DART deflected this asteroid. The results will help validate and improve scientific computer models critical to predicting the effectiveness of planetary defense technique as a reliable method for asteroid deflection.
Detailed Surveys Of Dimorphos and Didymos
Around four years from now, the European Space Agency’s Hera project will conduct detailed surveys of both Dimorphos and Didymos, with a particular focus on the crater left by DART’s collision and a precise measurement of Dimorphos’ mass.
DART’s celestial target was an oblong asteroid “moonlet” about 560 feet in diameter that orbits a parent asteroid five times larger called Didymos.
Chicxulub asteroid struck Earth some 66 million years ago, wiping out about three-quarters of the world’s plant and animal species including the dinosaurs. Dimorphos and Didymos are both tiny compared with this asteroid.
Also, the Dimorphos and Didymos asteroids relative proximity to Earth and dual configuration make them ideal for the first proof-of-concept mission of DART, short for Double Asteroid Redirection Test.
ROBOTIC SUICIDE MISSION
The mission represented a rare instance in which a NASA spacecraft had to crash to succeed. DART flew directly into Dimorphos at 24,000 kph, creating the force, enough to shift its orbital track closer to the parent asteroid.
The DART team said it expects to shorten the orbital path of Dimorphos by 10 minutes but would consider at least 73 seconds a success, proving the exercise as a viable technique to deflect an asteroid on a collision course with Earth-if one were ever discovered.
A small push to an asteroid millions of miles away years in advance could be sufficient to safely reroute it which in future can keep the Earth safe from asteroids.
NASA Spacecraft Crashing Into An Asteroid: Why?
In world’s first attempt to change the direction of an asteroid, scientists hope that this method can prevent collisions of asteroids with Earth.
The Dimorphos, smaller asteroid completes a lap around big Didymos every 11 hours and 55 minutes. The impact by DART should shave about 10 minutes off that. Although the strike itself should be immediately apparent, it could take a few weeks or more to verify the moonlet’s deflected orbit.
This will be observed by cameras on DART and a mini tagalong satellite will capture the collision up close. Telescopes on all seven continents, along with the Hubble and Webb space telescopes and NASA’s asteroid-hunting Lucy spacecraft, may see a bright flash as DART smacks Dimorphos and sends streams of rock and dirt cascading into space.
World’s First Planetary Defense Test By NASA Successful
The $330 million DART mission, after some seven years in development, was devised to determine if a spacecraft is capable of changing the trajectory of an asteroid through sheer kinetic force, changing its course just enough to keep Earth out of harm’s way.