NASA’s asteroid-deflecting DART spacecraft is approaching planned impact with its target asteroid Dimorphos.
Ten months after launch, NASA’s asteroid-deflecting DART spacecraft approached a planned collision with its target on Monday in a test of the world’s first planetary defense system designed to avoid a doomsday collision with Earth.
The cubic “impactor” vehicle, about the size of a vending machine with two rectangular solar panels, was on course to fly into the asteroid Dimorphos, about the size of a football stadium, and self-destruct at around 7 p.m. EDT (2300 GMT) approximately 11 million km from Earth.
The mission’s finale tests a spacecraft’s ability to alter an asteroid’s orbit with sheer kinetic force, plowing into the object at high speed to push it astray just enough to keep our planet out of danger.
It marks the world’s first attempt to alter the motion of an asteroid or other celestial body.
Launched by a SpaceX rocket in November 2021, DART has completed most of its journey led by NASA’s flight controllers, handing control over to an onboard autonomous navigation system in the final hours of the journey.
Monday night’s planned impact is to be monitored in real time from the Johns Hopkins University Applied Physics Laboratory (APL) mission center in Laurel, Maryland.
DART’s celestial target is an asteroid “moonlet” about 170 meters in diameter that orbits a five times larger mother planet called Didymos as part of a binary pair of the same name, the Greek word for twins. .
Neither object poses a real threat to Earth, and NASA scientists said their DART test cannot inadvertently create a new existential danger.
Dimorphos and Didymos are both small compared to the catastrophic Chicxulub asteroid that slammed into Earth some 66 million years ago, wiping out about three-quarters of the world’s plant and animal species, including dinosaurs.
Smaller asteroids are much more common and pose a bigger theoretical problem in the short term, making the Didymos pair suitable test subjects for their size, according to NASA scientists and planetary defense experts.
In addition, their relative proximity to Earth and double asteroid configuration make them ideal for DART’s first proof-of-concept mission, short for Double Asteroid Redirection Test.
ROBOTIC SELF-MISSION
The mission represents a rare case where a NASA spacecraft must eventually crash in order to succeed.
The plan is for DART to fly directly into Dimorphos at 25,000 miles per hour (24,000 km/h), crashing hard enough to bring its orbit closer to its larger companion asteroid.
Cameras on the impactor and on a briefcase-sized mini-spacecraft released from DART days in advance are designed to capture the collision and send images back to Earth.
DART’s own camera is expected to return images at a rate of one image per second during its final approach, with those images streamed live on NASA TV an hour before impact, according to APL.
The DART team said it expects to shorten Dimorphos’ orbit by 10 minutes, but would consider at least 73 seconds a success, showing the exercise is a viable technique to launch an asteroid on a collision course with Earth. to bend – if one were ever discovered. A small push toward an asteroid millions of miles away could be enough to safely lead it away from the planet.
The outcome of the test will not be known until another round of ground observations of the two asteroids in October. Previous calculations of Dimorphos’ takeoff location and orbital period were confirmed during a six-day observation period in July.
DART is the latest of several NASA missions in recent years to explore and interact with asteroids, primordial rocky remnants from the formation of the solar system more than 4.5 billion years ago.
Last year, NASA launched a probe on a journey to the Trojan asteroid clusters orbiting Jupiter, while the grab-and-go spacecraft OSIRIS-REx heads back to Earth with a sample collected from the asteroid in October 2020. Am now.
The Dimorphos moonlet is one of the smallest astronomical objects to receive a permanent name and is one of 27,500 known near-Earth asteroids of all sizes tracked by NASA. While it is known that there is no foreseeable danger to humanity, NASA estimates that many more asteroids remain undetected near Earth.
NASA has estimated the full cost of the DART project at $330 million, well below that of many of the space agency’s most ambitious science missions.