Before the impact, the moon took 11 hours and 55 minutes to circle its parent asteroid. Scientists had hoped to shave off 10 minutes, but Nelson said the impact shortened the asteroid’s orbit by about 32 minutes.
CAPE CANAVERAL, Fla. (AP) – A spacecraft that crashed into a small, harmless asteroid millions of miles away managed to change its orbit, NASA said Tuesday in announcing the results of its world-saving test.
The space agency attempted the test two weeks ago to see if a killer rock could be moved out of Earth’s path in the future.
“This mission shows that NASA is trying to be ready for whatever the universe throws at us,” NASA Administrator Bill Nelson said during a briefing at NASA headquarters in Washington.
The Dart spacecraft cut a crater in the asteroid Dimorphos on September 26, throwing debris into space and creating a comet-like trail of dust and debris that stretches several thousand kilometers. It took days of observations with telescopes from Chile and South Africa to determine how much the impact altered the 160-meter asteroid’s path around its companion, a much larger space rock.
Before the impact, the moon took 11 hours and 55 minutes to circle its parent asteroid. Scientists had hoped to shave off 10 minutes, but Nelson said the impact shortened the asteroid’s orbit by about 32 minutes.
The amount of debris apparently played a role in the outcome, the scientists said. The impact may also have caused Dimorphos to wobble a bit, said NASA program scientist Tom Statler. This may affect the orbit, but it will never return to its original orbit, he noted.
Neither asteroid posed a threat to Earth, and they still don’t as they continue their journey around the sun. That’s why scientists chose the pair for the world’s first attempt to alter the position of a celestial body.
Planetary defense experts prefer to ward off a threatening asteroid or comet with enough time, rather than blow it up and create multiple pieces that could rain down on Earth.
“It’s spectacular that we’ve taken this first step … but we really need to have that warning time for a technique like this to be effective,” said mission leader Nancy Chabot of the Johns Hopkins University Applied Physics Laboratory, which created the spacecraft and managed the $325 million mission.
“You have to know they’re coming,” said NASA’s Lori Glaze.
Launched last year, the vending machine-sized Dart (short for Double Asteroid Redirection Test) was destroyed when it hit the asteroid 7 million miles (11 million kilometers) away at 14,000 mph ( 22,500 kph).
“We’ve been imagining this for years and for it to finally be real is really exciting,” Statler said.
___
The Associated Press Department of Health and Science is supported by the Department of Science Education at the Howard Hughes Medical Institute. The AP is solely responsible for all content.
Marcia Dunn, The Associated Press