27 September, 2022 | 12:24 AM
NASA spacecraft crashes into asteroid in rare defense test
A NASA spacecraft rammed an asteroid at blistering speed Monday in an unprecedented dress rehearsal for the day a killer rock menaces Earth. The galactic slam occurred at a harmless asteroid 7 million miles (11.3 million kilometres) away, with the spacecraft named Dart plowing into the space rock at 14,000 mph (22,500 kph). Scientists expected the impact to carve out a crater, hurl streams of rocks and dirt into space and, most importantly, alter the asteroid’s orbit. “We have impact!” Mission Control’s Elena Adams announced, jumping up and down and thrusting her arms skyward. Don't want to miss a thing? Watch the final moments from the #DARTMission on its collision course with asteroid Dimporphos. pic.twitter.com/2qbVMnqQrD — NASA (@NASA) September 26, 2022 Telescopes around the world and in space aimed at the same point in the sky to capture the spectacle. Though the impact was immediately obvious — Dart’s radio signal abruptly ceased — it will be days or even weeks to determine how much the asteroid’s path was changed. The $325 million mission was the first attempt to shift the position of an asteroid or any other natural object in space. “We’re embarking on a new era of humankind,” said NASA’s Lori Glaze, planetary science division director. “The dinosaurs didn’t have a space program to help them know what was coming, but we do” Earlier in the day, NASA Administrator Bill Nelson reminded people via Twitter that, “No, this is not a movie plot.” He added in a prerecorded video: ”We’ve all seen it on movies like ‘Armageddon,’ but the real-life stakes are high.” Monday’s target: a 525-foot (160-meter) asteroid named Dimorphos. It’s actually a moonlet of Didymos, Greek for twin, a fast-spinning asteroid five times bigger that flung off the material that formed the junior partner. The pair have been orbiting the sun for eons without threatening Earth, making them ideal save-the-world test candidates. Launched last November, the vending machine-size Dart — short for Double Asteroid Redirection Test — navigated to its target using new technology developed by Johns Hopkins University’s Applied Physics Laboratory, the spacecraft builder and mission manager. Scientists insisted Dart would not shatter Dimorphos. The spacecraft packed a scant 1,260 pounds (570 kilograms), compared with the asteroid’s 11 billion pounds (5 billion kilograms). But that should be plenty to shrink its 11-hour, 55-minute orbit around Didymos. The non-profit B612 Foundation, dedicated to protecting Earth from asteroid strikes, has been pushing for impact tests like Dart since its founding by astronauts and physicists 20 years ago. Photo: Niketh Vellanki. The impact should pare 10 minutes off that, but telescopes will need anywhere from a few days to nearly a month to verify the new orbit. The anticipated orbital shift of 1 per cent might not sound like much, scientists noted. But they stressed it would amount to a significant change over years. Planetary defense experts prefer nudging a threatening asteroid or comet out of the way, given enough lead time, rather than blowing it up and creating multiple pieces that could rain down on Earth. Multiple impactors might be needed for big space rocks or a combination of impactors and so-called gravity tractors, not-yet-invented devices that would use their own gravity to pull an asteroid into a safer orbit. “The dinosaurs didn’t have a space program to help them know what was coming, but we do,” NASA’s senior climate adviser Katherine Calvin said, referring to the mass extinction 66 million years ago believed to have been caused by a major asteroid impact, volcanic eruptions or both.