NASA’s Hubble Telescope captures DART’s collision with asteroid Dimorphos

The National Aeronautics and Space Administration (NASA) Hubble Space Telescope captured a series of photos of the asteroid Dimorphos when it was deliberately hit by a 1,200-pound NASA spacecraft called DART on September 26, 2022, according to their statement.

Hubble’s time-lapse movie of the aftermath of the DART collision reveals startling and remarkable hour-by-hour changes as dust and bits of debris were hurled into space, NASA said in its statement.

Crashing head-on into the asteroid at 13,000 miles per hour, the DART impactor blasted more than 1,000 tons of dust and rock out of the asteroid.

The Hubble movie offers invaluable new clues as to how the debris was dispersed in a complex pattern in the days after impact, NASA said.

It was over a much larger volume of space than could be recorded by the LICIACube cubesat, which flew by the binary asteroid minutes after the DART impact, they said.

The main purpose of DART, which stands for Double Asteroid Redirection Test, was to test our ability to alter the asteroid’s trajectory as it orbits its larger companion asteroid, Didymos, the agency said.

Although neither Didymos nor Dimorphos pose a threat to Earth, data from the mission will help inform researchers on how to potentially divert an asteroid’s path away from Earth, if ever necessary, the statement said.

The DART experiment also provided new information about planetary collisions that may have been common in the early solar system.

“The DART impact occurred in a binary asteroid system. We’ve never seen an object collide with an asteroid in a binary asteroid system before in real time, and that’s really amazing.

“I think it’s fantastic. There’s too much going on here. It’ll take time to figure it out,” said Jian-Yang Li of the Planetary Science Institute in Tucson, Arizona.

The study, led by Li along with 63 other members of the DART team, was published March 1 in the journal Nature.

The film shows three overlapping stages after impact: the formation of an ejecta cone, the spiraling swirl of debris caught up along the asteroid’s orbit around its companion asteroid, and the swept tail behind the asteroid by the pressure of sunlight, resembling a windsock. caught in a breeze, according to the statement.

The statement describes that the Hubble movie begins 1.3 hours before impact.

In this view, Didymos and Dimorphos are both in the central bright spot; even Hubble can’t resolve the two asteroids separately.

The thin, straight spikes protruding from the center (and seen in later images) are artifacts of Hubble’s optics.

The first post-impact snapshot is 2 hours after the event.

Debris flies off the asteroid, moving at speeds over four miles per hour, fast enough to escape the asteroid’s gravitational pull, so it doesn’t fall back on the asteroid, says the press release.

The ejecta forms a broadly hollow cone with long stringy filaments.

About 17 hours after impact, the debris pattern entered a second stage.

The dynamic interaction within the binary system begins to distort the conical shape of the ejecta pattern, the statement described.

The most important structures are revolving elements in the form of a pinwheel. The pinwheel is tied to the gravitational pull of the companion asteroid, Didymos.

“It’s really unique for this particular incident,” Li said. “When I first saw these images, I couldn’t believe these features. I thought maybe the image was stained or something like that.” Hubble then captures the debris being pulled back into a comet-like tail by the pressure of sunlight on the tiny dust particles, the statement said.

This extends into a debris train where the lightest particles travel fastest and furthest from the asteroid. The mystery is compounded later when Hubble records the tail splitting in two for a few days, according to the release.

A multitude of other telescopes on Earth and in space, including NASA’s James Webb Space Telescope and the Lucy spacecraft, have also observed the DART impact and its results.

This Hubble movie is part of a series of new studies published in the journal Nature on the DART mission.

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