A NASA spacecraft rammed an asteroid at blistering speed Monday in an unprecedented dress rehearsal for the day a killer rock menaces Earth.

The galactic slam occurred at a harmless asteroid 7 million miles (11.3 million kilometers) away, with the spacecraft named Dart plowing into the space rock at 14,000 mph (22,500 kph). Scientists expected the impact to carve out a crater, hurl streams of rocks and dirt into space and, most importantly, alter the asteroidB次元官网网址檚 orbit.

B次元官网网址淲e have impact!B次元官网网址� Mission ControlB次元官网网址檚 Elena Adams announced, jumping up and down and thrusting her arms skyward.

Telescopes around the world and in space aimed at the same point in the sky to capture the spectacle. Though the impact was immediately obvious B次元官网网址� DartB次元官网网址檚 radio signal abruptly ceased B次元官网网址� it will be days or even weeks to determine how much the asteroidB次元官网网址檚 path was changed.

was the first attempt to shift the position of an asteroid or any other natural object in space.

B次元官网网址淲eB次元官网网址檙e embarking on a new era of humankind,B次元官网网址� said NASAB次元官网网址檚 Lori Glaze, planetary science division director.

Earlier in the day, NASA Administrator Bill Nelson reminded people via Twitter that, B次元官网网址淣o, this is not a movie plot.B次元官网网址� He added in a prerecorded video: B次元官网网址漌eB次元官网网址檝e all seen it on movies like B次元官网网址楢rmageddon,B次元官网网址� but the real-life stakes are high.B次元官网网址�

MondayB次元官网网址檚 target: a 525-foot (160-meter) asteroid named Dimorphos. ItB次元官网网址檚 actually a moonlet of Didymos, Greek for twin, a fast-spinning asteroid five times bigger that flung off the material that formed the junior partner.

The pair have been orbiting the sun for eons without threatening Earth, making them ideal save-the-world test candidates.

, the vending machine-size Dart B次元官网网址� short for Double Asteroid Redirection Test B次元官网网址� navigated to its target using new technology developed by Johns Hopkins UniversityB次元官网网址檚 Applied Physics Laboratory, the spacecraft builder and mission manager.

DartB次元官网网址檚 on-board camera, a key part of this smart navigation system, caught sight of Dimorphos barely an hour before impact.

B次元官网网址淲oo hoo,B次元官网网址� exclaimed Adams, a mission systems engineer at Johns Hopkins. B次元官网网址淲eB次元官网网址檙e seeing Dimorphos, so wonderful, wonderful.B次元官网网址�

With an image beaming back to Earth every second, Adams and other ground controllers in Laurel, Maryland, watched with growing excitement as Dimorphos loomed larger and larger in the field of view alongside its bigger companion. Within minutes, Dimorphos was alone in the pictures; it looked like a giant gray lemon, but with boulders and rubble on the surface. The last image froze on the screen as the radio transmission ended.

Flight controllers cheered, hugged one another and exchanged high fives.

A mini satellite followed a few minutes behind to take photos of the impact. The Italian Cubesat was released from Dart two weeks ago.

Scientists insisted Dart would not shatter Dimorphos. The spacecraft packed a scant 1,260 pounds (570 kilograms), compared with the asteroidB次元官网网址檚 11 billion pounds (5 billion kilograms). But that should be plenty to shrink its 11-hour, 55-minute orbit around Didymos.

The impact should pare 10 minutes off that, but telescopes will need anywhere from a few days to nearly a month to verify the new orbit. The anticipated orbital shift of 1% might not sound like much, scientists noted. But they stressed it would amount to a significant change over years.

Planetary defense experts prefer nudging a threatening asteroid or comet out of the way, given enough lead time, rather than blowing it up and creating multiple pieces that could rain down on Earth. Multiple impactors might be needed for big space rocks or a combination of impactors and so-called gravity tractors, not-yet-invented devices that would use their own gravity to pull an asteroid into a safer orbit.

B次元官网网址淭he dinosaurs didnB次元官网网址檛 have a space program to help them know what was coming, but we do,B次元官网网址� NASAB次元官网网址檚 senior climate adviser Katherine Calvin said, referring to the mass extinction 66 million years ago believed to have been caused by a major asteroid impact, volcanic eruptions or both.

The non-profit B612 Foundation, dedicated to protecting Earth from asteroid strikes, has been pushing for impact tests like Dart since its founding by astronauts and physicists 20 years ago. MondayB次元官网网址檚 feat aside, the world must do a better job of identifying the countless space rocks lurking out there, warned the foundationB次元官网网址檚 executive director, Ed Lu, a former astronaut.

Significantly less than half of the estimated 25,000 near-Earth objects in the deadly 460-foot (140-meter) range have been discovered, according to NASA. And fewer than 1% of the millions of smaller asteroids, capable of widespread injuries, are known.

The Vera Rubin Observatory, nearing completion in Chile by the National Science Foundation and U.S. Energy Department, promises to revolutionize the field of asteroid discovery, Lu noted.

Finding and tracking asteroids, B次元官网网址淭hatB次元官网网址檚 still the name of the game here. ThatB次元官网网址檚 the thing that has to happen in order to protect the Earth,B次元官网网址� he said.

B次元官网网址擬arcia Dunn, The Associated Press