mission accomplished
NASA successfully crashed a spacecraft into an asteroid on Monday, marking a victory for the agency’s plan for when a devastating asteroid should ever threaten humanity.
The 1,260-pound Twin Asteroid Redirection Test spacecraft, or DART, collided with the estimated 11 billion-pound, 520-foot-long asteroid Dimorphos at 14,000 miles per hour about 7 million miles from the land The spacecraft impacted about 55 feet from the center of the asteroid.
The spacecraft had launched its camera and a shoebox-sized companion, LICIACube, more than a week ago to photograph the mission, which confirmed the impact.
“This was a really tough technology demonstration to hit a small asteroid that we’ve never seen before and do it in such a spectacular way,” said Nancy Chabot, a planetary scientist and mission team leader at Johns University. Hopkins, after impact.
The completed mission caps a 10-month journey for DART, which cost $325 million. The asteroid orbits a larger one called Didymos, and the two were chosen because they pose no threat to Earth.
“There was a lot of innovation and creativity in this mission, and I think it will teach us how to one day protect our own planet from an incoming asteroid,” said NASA Administrator Bill Nelson. “We are showing that planetary defense is a global effort and it is very possible to save our planet.”
VISUAL EXPLANATOR: Go inside NASA’s plan to crash the DART spacecraft into an asteroid
The DART team said no adjustments were needed to the mission and that it fell “right in the middle of our expectations.”
Although DART successfully hit Dimorphos, NASA won’t know for weeks, possibly months, about the effects of the collision.
“Some things will probably come out in even days, maybe weeks,” mission systems engineer Elena Adams told reporters after the impact. “But I would say for the full quantitative response, a couple of months.”
The agency’s goal was not to destroy the asteroid, but to change its orbit around Didymos enough to change its trajectories. Dimorphos completes an orbit around Didymos in 11 hours and 55 minutes; NASA expects the collision to shorten its orbit by 10 minutes.
But changing an asteroid’s orbit by just 1% could be enough if a destructive one is headed for Earth, NASA says. Currently, there are nearly 30,000 near-Earth objects in our solar system, according to NASA, meaning they are within 120.8 million miles of our planet. More than 10,000 near-Earth objects feature them around the same size as Dimorphos.

Planetary defense experts prefer to ward off a threatening asteroid or comet, given enough time, rather than blow it up and create multiple pieces that could rain down on Earth. Multiple impactors might be needed for large space rocks, or a combination of impactors and so-called gravity tractors, yet-to-be-invented devices that would use their own gravity to pull an asteroid into a safer orbit.
Although no asteroids of this size are expected to reach Earth in the next 100 years, only 40% of these asteroids have been discovered as of October 2021, NASA says. Less than 1% of the millions of smaller asteroids capable of widespread injury are known.
But for now, astronomers say humanity should feel safe.
“Our first planetary defense test was a success,” Adams said. “Earthlings should sleep better.”
Contributor: Associated Press
Follow Jordan Mendoza on Twitter: @jordan_mendoza5.