Oct 13, 2022
NASA’s Double Asteroid Redirection Test (DART) proved successful. It changed an asteroid’s path. That raises hopes that humans can protect the planet from being hit by a large asteroid.
It happened September 26. It marked the first time ever that humans altered the course of a non-man-made object in space. The experiment required a $330 million spacecraft to be destroyed. The test was even more successful than scientists had hoped.
NASA crashed DART into an asteroid named Dimorphos on purpose. The goal was to push the asteroid into a shorter orbit around its larger companion, Didymos. NASA accomplished that. It sliced a full 32 minutes off the rock’s orbit. Scientists said they would have been thrilled if they’d shortened that orbit by just 10 minutes.
Both asteroids follow a nonstop, 770-day space flight between the Sun and outside the orbit of Mars. Dimorphos’ collision with the spacecraft occurred nearly 7 million miles from Earth. So, the experiment never posed any danger to us.
The craft was the size of a refrigerator. It traveled at 14,000 mph.
“We conducted humanity’s first planetary defense test,” a NASA official told reporters. “We showed the world that NASA is serious as a defender of this planet.”
Extinction-event asteroids have struck the planet before. One is believed to have doomed the dinosaurs. Scientists say another one will likely crash into Earth at some point. Scientists already track the giant ones. Those are much easier to find than smaller ones. Dimorphos is a smaller asteroid. It's 163 meters wide. An asteroid Dimorphos’ size could ruin a large city. The resulting crater would be a mile wide. The rock would destroy many buildings.
Photo from Reuters.
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