NASA’s DART spacecraft successfully blasted past a distant asteroid at hypersonic speeds on Monday, in the world’s first test of a planetary defense system designed to prevent a potentially doomsday meteorite collision with Earth.
Humanity’s first attempt to change the motion of an asteroid or any celestial body in a NASA webcast from the Mission Operations Center outside Washington, DC, 10 months after DART’s launch.
The livestream showed images taken by DART’s cameras as the cube-shaped “impactor” vehicle, no bigger than a vending machine with two rectangular solar arrays, at 7:14 p.m. EDT, disintegrated into an asteroid the size of a football stadium. (23:14 GMT) about 6.8 million miles (11 million km) from Earth.
The $330 million (roughly Rs. 2,683 crore) mission, about seven years in development, was designed to determine whether a spacecraft would be able to change the trajectory of an asteroid through sheer kinetic energy, enough to keep it away from Earth. path of harm.
Whether the experiment succeeded beyond its intended effect will not be known until next month’s ground-based telescope observations of the asteroid. But NASA officials welcomed the immediate results of Monday’s test, saying the spacecraft accomplished its purpose.
“NASA works to benefit humanity, so for us to do something like this is the ultimate fulfillment of our mission — a demonstration of technology that, who knows, could one day save our planet,” NASA Deputy Administrator Pam Melroy, a retired astronaut, said minutes after the impact.
DART, launched by a SpaceX rocket in November 2021, flew most of its journey under the guidance of NASA’s flight director, handing over control to an autonomous on-board navigation system in the final hours of the journey.
Monday evening’s bullseye effect was monitored in near real time from the mission operations center at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.
Second-by-second images of the target asteroid captured by DART’s onboard cameras zoomed in and filled the TV screen of NASA’s live webcast before finally losing signal and cheers from the control room confirming the spacecraft had crashed in Dimorphos. .
DART’s celestial target was a rectangular asteroid “moonlet” about 560 feet (170 m) in diameter that orbits a five-times larger 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 accidentally create a new threat.
Both Dimorphos and Didymos are small compared to the cataclysmic Chicxulub asteroid that hit Earth about 66 million years ago, wiping out about three-quarters of the world’s plant and animal species, including the dinosaurs.
According to NASA scientists and planetary protection experts, smaller asteroids are more common and pose a major theoretical concern in the near term, making the Didymos pair a perfect test subject for their size. A dimorphos-sized asteroid, while not capable of posing a planet-wide threat, can level a large city with a direct hit.
Also, the two asteroids’ relative proximity to Earth and dual configuration make them ideal for DART’s first proof-of-concept mission, short for Dual Asteroid Redirection Test.
Robotic suicide mission
This mission is a rare instance in which a NASA spacecraft had to crash to succeed. DART flew directly into Dimorphos at a speed of 15,000 miles per hour (24,000 kph), which scientists hope will be enough to move its orbital track closer to the parent asteroid.
APL engineers said the spacecraft broke apart and made a small impact on the rocky surface of the asteroid.
The DART team said it expects to shorten Dimorphos’ orbital path by 10 minutes but is expected to be successful by at least 73 seconds, making the exercise a viable technique for deflecting asteroids on a collision course with Earth — if one is discovered.
Pushing an asteroid millions of miles away several years in advance may be enough to safely pass it by.
Dimorphos’ initial position and orbital period were previously calculated during a six-day observation period in July and will be compared with post-impact measurements made in October to determine if and how much the asteroid sank.
Monday’s test was also observed by a camera mounted on a briefcase-sized mini-spacecraft launched from DART, as well as by ground-based observatories and the Hubble and Webb Space Telescopes, but images from those were not immediately available.
DART is the latest of several NASA missions in recent years to explore and interact with asteroids, primitive rocky remnants from the formation of the Solar System 4.5 billion years ago.
Last year, NASA launched an investigation into the journey of the Trojan asteroid clusters orbiting Jupiter, while the OSIRIS-REx spacecraft is returning to Earth with a sample collected from asteroid Bennu in October 2020.
Dimorphos Moonlet is one of the smallest celestial objects to receive 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 an imminent threat to mankind, NASA estimates that many asteroids in the near-Earth vicinity have yet to be discovered.
© Thomson Reuters 2022
