NASA’s DART spacecraft hits target asteroid in first planetary defense test

September 26 (Reuters) – NASA’s DART spacecraft successfully slammed into a distant asteroid at hypersonic speed on Monday in the world’s first test of a planetary defense system, designed to prevent a possible apocalyptic meteorite collision with the Earth.

Humanity’s first attempt to alter the motion of an asteroid or any celestial body took place in a NASA webcast from the mission operations center outside Washington, DC, 10 months after launching DART.

The live stream showed footage taken by DART’s camera as the cube-shaped “impactor” vehicle, no bigger than a vending machine with two rectangular solar panels, streaked into the asteroid Dimorphos, about the size of a football stadium, at 7:14 p.m. EDT (2314 GMT) some 6.8 million miles (11 million km) from Earth.

The $330 million mission, around seven years in development, was designed to determine if a spacecraft is capable of altering the trajectory of an asteroid by sheer kinetic force, pushing it just enough to keep Earth out of harm’s way. .

Whether the experiment succeeded beyond the predicted impact will not be known until further ground-based telescope observations of the asteroid next month. But NASA officials hailed the immediate result of Monday’s test, saying the spacecraft had achieved its goal.

“NASA works for the benefit of mankind, so for us, it’s the ultimate fulfillment of our mission to do something like this – a demonstration of technology that, who knows, one day might save our home,” said said Pam Melroy, NASA assistant administrator, a retired astronaut. , said a few minutes after the impact.

DART, launched by a SpaceX rocket in November 2021, completed most of its journey under the direction of NASA flight directors, with control handed over to an autonomous onboard navigation system in the final hours of the trip.

Monday night’s bullseye impact was monitored in near real-time from the Mission Operations Center at Johns Hopkins University’s Applied Physics Laboratory in Laurel, Maryland.

Cheers erupted from the control room as second-by-second images of the target asteroid, captured by DART’s on-board camera, grew and eventually filled the television screen of NASA’s live webcast. just before the signal was lost, confirming that the spacecraft had crashed into Dimorphos.

DART’s celestial target was an oblong asteroid “moonlet” about 170 meters in diameter that orbits a five times larger parent asteroid called Didymos as part of a binary pair of the same name, the Greek word for twin.

Neither object poses any real threat to Earth, and NASA scientists said their DART test could not mistakenly create a new hazard.

Both Dimorphos and Didymos are tiny compared to the cataclysmic asteroid Chicxulub that hit Earth around 66 million years ago, wiping out around three-quarters of the world’s plant and animal species, including dinosaurs.

Smaller asteroids are far more common and of greater near-term theoretical concern, making the Didymos pair suitable test subjects for their size, according to NASA scientists and planetary defense experts. A Dimorphos-sized asteroid, while incapable of posing a planet-wide threat, could level a major city with a direct hit.

Additionally, the two asteroids’ relative proximity to Earth and their dual configuration make them ideal for the first proof-of-concept mission of DART, short for Double Asteroid Redirection Test.

ROBOTIC SUICIDE MISSION

The mission represented a rare case in which a NASA spacecraft had to crash to succeed. DART flew directly into Dimorphos at 15,000 miles per hour (24,000 km/h), creating the force scientists hope is enough to shift its orbital path closer to the parent asteroid.

PLA engineers said the spacecraft had likely been shattered and left a small impact crater in the rock-strewn surface of the asteroid.

The DART team said they planned to shorten Dimorphos’ orbital path by 10 minutes, but would consider at least 73 seconds a success, proving the exercise is a viable technique for deflecting an asteroid on a trajectory. collision with Earth – if ever found.

A nudge at an asteroid millions of miles years ahead could be enough to redirect it safely.

Earlier calculations of Dimorphos’ departure location and orbital period were made during a six-day observation period in July and will be compared with post-impact measurements made in October to determine if the asteroid moved and by how much.

Monday’s test was also observed by a camera mounted on a briefcase-sized mini-spacecraft released from DART days in advance, as well as by ground-based observatories and the Hubble and Webb Space Telescopes, but images of these were not immediately available.

DART is the latest of several NASA missions in recent years to explore and interact with asteroids, primordial rock remnants from the formation of the solar system more than 4.5 billion years ago.

Last year, NASA launched a probe on a trip to the Trojan asteroid clusters orbiting near Jupiter, while the take-home spacecraft OSIRIS-REx is on its way back to Earth with a sample collected in October 2020 from the asteroid Bennu.

The moon Dimorphos is one of the smallest astronomical objects to be given a permanent name and is one of 27,500 known near-Earth asteroids of all sizes tracked by NASA. Although none are known to pose any foreseeable danger to humanity, NASA believes that many other asteroids remain undetected in Earth’s near vicinity.

(This story corrects name in paragraph 6 to Pam from Palm)

Reporting by Steve Gorman in Los Angeles; Additional reporting by Joey Roulette in Los Angeles; Editing by Sandra Maler and Stephen Coates

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