The James Webb and Hubble telescopes revealed their first images on Thursday of a spacecraft deliberately crashing into an asteroid, as astronomers said the impact appears to have been much larger than expected.
Telescopes around the world turned their gaze to the space rock Dimorphos earlier this week for a historic test of Earth’s ability to defend against a potentially deadly asteroid in the future.
Astronomers rejoiced when NASA’s Double Asteroid Redirection Test (DART) impactor slammed into its pyramid-sized rugby ball-shaped target 11 million kilometers (6.8 million miles) away. Earth Monday evening.
Images taken by Earth-bound telescopes showed a vast cloud of dust extending out of Dimorphos – and its bigger brother Didymos on which it orbits – after the spacecraft impact.
While those images showed material being sputtered thousands of miles away, the James Webb and Hubble images “zoom much closer,” said Alan Fitzsimmons, an astronomer at Queen’s University Belfast involved in the ATLAS project observations. .
James Webb and Hubble can provide a view “just a few miles from the asteroids and you can really clearly see how material is flying out of that explosive DART impact,” Fitzsimmons told AFP.
“It’s really quite spectacular,” he said.
An image taken by James Webb’s near-infrared camera (NIRCam) four hours after the impact shows “plumes of material appearing as streaks moving away from the center of where the impact occurred”, according to a joint statement by the European Space Agency, James Webb and Hubble.
Hubble images from 22 minutes, five hours and eight hours after impact show the jet of material expanding from where DART struck.
“I’m afraid there’s nothing left”
The European Space Agency’s Ian Carnelli said the “truly impressive” images of Webb and Hubble were remarkably similar to those taken by the toaster-sized satellite LICIACube, which was just 50 kilometers away. asteroid after separating from the DART spacecraft a few weeks ago. .
The images show an impact that looks “much larger than we expected”, said Carnelli, ESA’s Hera mission manager, who intends to inspect the damage in four years.
“I was really scared there would be nothing left of Dimorphos” at first, Carnelli told AFP.
The Hera mission, due to launch in October 2024 and arrive at the asteroid in 2026, expected to probe a crater about 10 meters (33 feet) in diameter.
It now looks like it will be much bigger, Carnelli said, “if there’s a crater, maybe a piece of Dimorphos has just been ripped out.”
The true measure of DART’s success will be exactly how much it has diverted the asteroid’s trajectory, so the world can begin to prepare to defend against larger asteroids that may be heading our way in the future.
It will likely take ground-based telescopes and radars at least a week for an initial estimate of the asteroid’s orbital change, and three or four weeks before there’s an accurate measurement, Carnelli said.
“I expect a much larger deviation than we had anticipated,” he said.
This would have “huge implications in planetary defense because it means this technique could be used for much larger asteroids,” Carnelli added.
“Until today, we thought the only deflection technique would be to send a nuclear device.”
Fitzsimmons said that even if no material had been “ejected” from Dimorphos, DART would still have slightly affected its orbit.
“But the more material there is and the faster it moves, the more deviation there will have been,” he said.
Observations by James Webb and Hubble will help reveal how much — and how quickly — material is being sputtered by the asteroid, as well as the nature of its surface.
The asteroid impact marked the first time that both space telescopes observed the same celestial body.
Since launching in December and releasing its first images in July, James Webb has taken the title of Hubble’s most powerful space telescope.
Fitzsimmons said the images were “a nice demonstration of the extra science you can get from using more than one telescope simultaneously.”
© Agence France-Presse
#Hubble #Webb #Photos #Reveal #DARTs #Impact #Bigger #Expected