NASA will use a spacecraft later this month to test a planetary defense method that could one day save Earth.
The Double Asteroid Redirect Test spacecraft, also known as DART, will be used as a battering ram to crash into an asteroid not far from Earth on September 2. 26. The mission is an international collaboration to protect the world from future asteroid impacts.
“While the asteroid poses no threat to Earth, this is the world’s first test of the kinetic impact technique, using a spacecraft to deflect an asteroid for planetary defense,” NASA said Thursday.
In November 2021, a SpaceX Falcon 9 rocket with DART was launched from Vandenberg Air Force Base in California.
Now, 10 months later, DART will catch up with the asteroid executing three trajectory correction maneuvers over the next three weeks. Scientists say each maneuver will reduce the spacecraft’s required trajectory margin of error to impact the asteroid known as Dimorphos.
NASA says that after the final maneuver on September 2. On the 25th, approximately 24 hours before impact, the navigation team will know the position of Dimorphos within a radius of 2 kilometers. From there, DART will be on its own to autonomously guide itself to collide with the out-of-this-world space rock.
DART recently got its first look at Didymos, the double-asteroid system that includes its target, Dimorphos.
An image taken from 20 million miles away showed the Didymos system to be quite faint. Still, once a series of images were combined, astronomers were able to pinpoint the exact location of Dimorphos.
“By seeing the DRACO images of Didymos for the first time, we can define the best settings for DRACO and tune the software,” said Julie Bellerose, DART navigation lead at NASA’s Jet Propulsion Laboratory. “In September, we will refine where DART is headed by getting a more precise determination of Didymos’s location.”
If DART hits Dimorphos at 15,000 mph as planned, it will test the kinetic impactor theory of Earth’s defense.
“The target of a kinetic impactor is you ram your spaceship toward the asteroid you’re worried about, and then you change its orbit around the Sun by doing that.” Johns Hopkins Planetary Astronomer Applied Physics Laboratory Andy Rivkin said.
DART will not change the orbit of Didymos. Your goal is to change the speed of the little moon, Dimorphos. Ground telescopes and data of the spaceship he will eventually tell the scientists if his plan worked.
Asteroids move around the sun at a speed of about 20 miles per second. Rivkin explained that if a kinetic impact method were used to change its orbit, the engineers would only want to alter that by a small amount, perhaps an inch or two per second.
That’s why Didymos and its little moon Dimorphos make a perfect practice target. The small asteroid is orbiting Didymos and is moving about one foot per second, which is much easier to measure than 20 miles per second.
If this works, the idea is to apply the same technique to larger asteroids. Until this mission, scientists could only simulate such an impact in a laboratory. DART will provide you with data to help solidify this defense plan.
