More On: Phantom Galaxy
NASA is planning to crash a spacecraft on purpose into an asteroid to help save Earth
Phantom Galaxy looks more beautiful than ever in new photos
NASA will use a spacecraft at the end of the month to test a way to protect Earth that could save it one day.
On Sept. 26, a spacecraft called DART, or Double Asteroid Redirect Test, will be used as a battering ram to crash into an asteroid not too far from Earth. The mission is a group effort from all over the world to keep the Earth safe from future asteroid hits.
NASA said Thursday that the asteroid doesn't pose a threat to Earth, but this is the first time a spacecraft has been used to deflect an asteroid as a way to protect the planet.
In November 2021, a SpaceX Falcon 9 rocket carrying DART took off from California's Vandenberg Air Force Base.
Now, 10 months later, DART will catch up with the asteroid by making three course corrections over the next three weeks. Scientists say that each maneuver will make the spacecraft's required path to hit the asteroid called Dimorphos more accurate.
NASA says that the navigation team will know where Dimorphos is within 2 kilometers after the last maneuver on September 25. This is about 24 hours before impact. From there, DART will be on its own to drive itself toward the space rock from another planet.
Recently, DART got its first look at Didymos, a double-asteroid system that includes Dimorphos, its target.
From 20 million miles away, a picture of the Didymos system showed that it was very faint. Still, when astronomers put together a number of images, they could figure out exactly where Dimorphos was.
Julie Bellerose, the DART navigation lead at NASA's Jet Propulsion Laboratory, said, "When we see the DRACO images of Didymos for the first time, we can figure out the best settings for DRACO and fine-tune the software." "In September, we'll make DART's target more accurate by getting a better idea of where Didymos is."
If DART hits Dimorphos at 15,000 mph as planned, it will test the theory that the Earth's defenses can protect it from kinetic impacts.
Andy Rivkin, a planetary astronomer at the Johns Hopkins Applied Physics Laboratory, said, "The point of a kinetic impactor is to crash your spacecraft into the asteroid you're worried about. This changes its path around the Sun."
Didymos' path won't change because of DART. Its goal is to change the speed of Dimorphos, a small moon. Scientists will find out if their plan worked or not when they look at data from the spacecraft and data from telescopes on the ground.
Asteroids move about 20 miles per second around the sun. Rivkin said that if kinetic impactors were used to change its orbit, engineers would only want to change it by a small amount, maybe an inch or two a second.
So, Didymos and its little moon Dimorphos are great places to practice. The tiny asteroid goes around Didymos and moves about a foot per second, which is much easier to measure than 20 miles per second.
If this works, the same method could be used on bigger asteroids. Before this mission, scientists could only make an impact like this in the lab. DART will give them information that will help make this defense plan stronger.
