NASA's Double Asteroid Redirection Test (DART) has blasted off on a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California, making it the space agency's "first planetary defense test to intentionally crash into an asteroid." NASA noted it was "the world’s first mission to asteroid-deflecting technology" as well. DART will cruise for 10 months to a binary asteroid system.
The idea is that if humans have adequate time to react—decades of notice being preferable—enough energy can be transferred into a speeding rock to alter its trajectory and make it miss Earth, avoiding catastrophe up to and including an extinction-level event. (Though a popular subject in science fiction, it’s worth noting that NASA’s current toolkit of asteroid-nudging techniques does not include Morgan Freeman, Bruce Willis or nuclear weapons.)
Given the critical nature of the work, it’s “not a stretch to suggest that DART may be one of the most consequential missions ever undertaken by NASA,” Casey Dreier, an analyst with The Planetary Society, wrote in a November memo to members.
“This test is to demonstrate that this technology is mature enough so that it would be ready if an actual asteroid impact threat were detected,” Lindley Johnson, NASA’s planetary defense officer, said at a Nov. 4 news conference.
In September of next year—if all goes as planned—the DART craft will target Dimorphos, the smaller, 530-foot rocky body gravitationally tied to the larger Didymos, which is almost 2,600 feet across. The two rocks travel about 1 kilometer (0.6 mile) apart, and Dimorphos orbits its larger sibling every 11 hours and 55 minutes, “just like clockwork,” Johnson said.
Traveling at about 15,000 mph, the craft, which weighs 1,344 pounds and is 59 feet across, is to collide head-on with Dimorphos to both slow the rock by a fraction of a second and to adjust its orbital period around the larger asteroid by several minutes.
Didymos was discovered 25 years ago and has been well-analyzed (insofar as asteroids and comets go). Its course isn’t predicted to meet Earth in the future, but its relatively close trajectory gives scientists a good test platform to observe with telescopes from about 6.8 million miles away.
DART will use laser targeting and other high-resolution technologies to autonomously choose its impact point. As it races toward the rock, the craft’s camera will send images back to Earth. A small cube-satellite released from the main craft before impact will also record images from a safe distance. One big unknown: The smaller body’s surface composition and topography, which are too small to ascertain from Earth.
For more than 15 years, NASA has been under Congressional orders to catalog near-Earth objects (NEOs) larger than 140 meters (460 feet), the size at which an asteroid strike would cause enormous devastation. “While no known asteroid larger than 140 meters in size has a significant chance to hit Earth for the next 100 years, less than half of the estimated 25,000 NEOs that are 140 meters and larger in size have been found to date,” according to NASA’s Planetary Defense Coordination Office.
NASA plans additional testing of its trajectory-altering techniques once it has data from DART’s destruction at Dimorphos, assuming the mission is successful.
A “gravity tractor” is another idea under active consideration, the concept being to attach a spacecraft to an asteroid to enlarge its mass and slowly change its orbit.
Still, observation is critical to preventing a repeat of the fate that befell the dinosaurs. NASA and other scientists are laboring under last year’s loss of the Arecibo Observatory in Puerto Rico, which played a key role in radar assessments of near-Earth objects, helping researchers to determine their size and orbits. Says Johnson, the earth’s defender at NASA: “The key to planetary defense is finding them well before they are an impact threat.”
Subscribe to our YouTube channel: [ Ссылка ]
Subscribe to our newest channel Quicktake Explained: [ Ссылка ]
Bloomberg Quicktake brings you live global news and original shows spanning business, technology, politics and culture. Make sense of the stories changing your business and your world.
To watch complete coverage on Bloomberg Quicktake 24/7, visit [ Ссылка ], or watch on Apple TV, Roku, Samsung Smart TV, Fire TV and Android TV on the Bloomberg app.
Have a story to tell? Fill out this survey for a chance to have it featured on Bloomberg Quicktake: [ Ссылка ]
Connect with us on…
YouTube: [ Ссылка ]
Breaking News on YouTube: [ Ссылка ]...
Twitter: [ Ссылка ]
Facebook: [ Ссылка ]
Instagram: [ Ссылка ]
