See video of the moment NASA's DART spacecraft crashed itself into an asteroid and its livestream cut out

• NASA crashed a space probe into an asteroid on Monday night, practicing to deflect dangerous space rocks.
• The Double Asteroid Redirection Test (DART) hit the space rock in an effort to change its orbit.

NASA just slammed a spacecraft into a distant asteroid in the name of planetary defense.

The asteroid, called Dimorphos, poses no threat to Earth. But the Double Asteroid Redirection Test (DART) was designed for low stakes. NASA wants to see if it can change a space rock's orbit — just in case it ever discovers a large one bound for Earth.

"We're embarking on a new era of humankind, an era in which we potentially have the capability to protect ourselves from something like a dangerous, hazardous asteroid impact," Lori Glaze, director of NASA's planetary science division, said on a livestream shortly after the DART impact.

After 10 months of traveling to the distant, desolate rock, DART finally reached its destination — and met its demise — at 7:14 p.m. ET on Monday. In the final minutes, a livestream from the spacecraft's camera showed Dimorphos coming into clear view.

Giant boulders on its surface came into resolution, then smaller boulders as DART careened closer to its target, then the tiny rocks on the asteroid's surface just before the feed cut out. As NASA planned, DART crashed into the craggy surface and its camera feed died. Watch those final moments, below.

The DART control room erupted in applause, cheers, and cries of congratulations.

"Never before have I been so excited to see a signal go away, and an image to stop," Ralph Semmel, director of Johns Hopkins' Applied Physics Laboratory, which developed the spacecraft, said on NASA's live broadcast.

"Normally, losing signal from a spacecraft is a very bad thing, but in this case it was the ideal outcome," he added in a briefing.

DART hit the asteroid about 17 meters from its center — a bullseye in astronomical scales.

Now, more work begins. Astronomers are poised to point their telescopes to Dimorphos as it continues to orbit a much larger asteroid called Didymos. DART's goal was to give Dimorphos just enough of a bump to change its orbit by about 1%. If everything went as expected, it should have moved closer to the larger rock.

Data from those follow-up observations will be crucial if NASA ever needs to launch an asteroid-bumping mission to deflect a real threat to Earth.