Mission alters asteroid's motion, NASA confirms

LOS ANGELES — NASA's Double Asteroid Redirection Test mission has successfully changed the orbit of the asteroid Dimorphos when the NASA spacecraft intentionally slammed into the space rock, the agency said on Tuesday.

This marked the first time that humanity has purposely changed the motion of a celestial object and the first full-scale demonstration of asteroid deflection technology, NASA said.

Before DART's impact, it took Dimorphos 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos.

Since DART's intentional collision with Dimorphos on Sept 26, astronomers have been using telescopes on Earth to measure how much that time has changed.

The investigation team has confirmed the spacecraft's impact altered Dimorphos' orbit around Didymos by 32 minutes, shortening the orbit to 11 hours and 23 minutes.

Rusty Schweickart, Apollo astronaut and co-founder of the nonprofit B612 Foundation, said he is "clearly delighted, no question about that" by the results and the attention the mission has brought to asteroid deflection.

The DART mission aims to shift an asteroid's orbit through kinetic impact, in order to test and validate a method to protect Earth in case of an asteroid impact threat, NASA said.

The DART spacecraft was launched on Nov 24, 2021, and spent 10 months journeying to its asteroid target.

The team's scientists said the amount of debris apparently played a role in the outcome. The impact may also have left Dimorphos wobbling a bit, NASA program scientist Tom Statler said. That may affect the orbit, but it will never go back to its original location.

Team scientists cautioned more work is needed to not only identify more of the countless space rocks out there, but to also ascertain their makeup — some are solid, while others are rubble piles.

Scouting missions might be needed, for instance, before launching impactors to deflect the orbits. "We should not be too eager to say one test on one asteroid tells us exactly how every other asteroid would behave in a similar situation," Statler said.

Agencies - Xinhua