Skip to main content

Hubble observes a cluster of boulders around impacted asteroid Dimorphos

Last year, NASA deliberately crashed a spacecraft into an asteroid, in a first-of-its-kind test of planetary defense. At the time, telescopes around the world including the Hubble Space Telescope observed the impact between the DART spacecraft and the Dimorphos asteroid, capturing footage of the plumes of dust thrown up. Now, Hubble has observed Dimorphos once again and seen that a number of boulders have been ejected from the asteroid.

The Hubble image shown below was taken on 19 December 2022, around four months after the impact, and shows the bright streak of the asteroid across the sky, surrounded by small boulders which were knocked loose during the impact. This view was only possible after several months as the impact initially sent up large amounts of dust which made it difficult to see the asteroid in detail.

A NASA/ESA Hubble Space Telescope image of the asteroid Dimorphos taken on 19 December 2022.
This NASA/ESA Hubble Space Telescope image of the asteroid Dimorphos was taken on 19 December 2022, nearly four months after the asteroid was impacted by NASA’s DART (Double Asteroid Redirection Test) mission. Hubble’s sensitivity reveals a few dozen boulders knocked off the asteroid by the force of the collision. These are among the faintest objects Hubble has ever photographed inside the Solar System. The ejected boulders range in size from 1 metre to 6.7 metres across, based on Hubble photometry. They are drifting away from the asteroid at around a kilometre per hour. The discovery yields invaluable insights into the behaviour of a small asteroid when it is hit by a projectile for the purpose of altering its trajectory. NASA, ESA, D. Jewitt (UCLA)

Researchers observed 37 boulders in total, ranging in size from 1 to 6.7 meters. The aim of the impact was not to destroy the asteroid but to redirect it — the idea being that, in case an asteroid were threatening Earth, this method could be effective at nudging its orbit so that it would miss the planet. The recent observations also gave further confirmation that the asteroid’s trajectory around its partner asteroid, Didymos. However, to learn more about the exact effects of the impact, we will have to wait for the European Space Agency’s Hera mission, which will visit the asteroid binary to collect more data and which will launch next year.

Recommended Videos

In total, around 0.1% of the mass of the Dimorphos asteroid was displaced by the impact, with the boulders now drifting away from the asteroid. Hubble scientists explain that these are probably not made from chunks of the asteroid, but rather are boulders that were sitting on the asteroid’s surface when the impact occurred.

Please enable Javascript to view this content

“It’s not clear how the boulders were lifted off the asteroid’s surface,” Hubble scientists write. “They could be part of an ejecta plume that was photographed by Hubble and other observatories. Or a seismic wave from the impact may have rattled through the asteroid — like hitting a bell with a hammer — shaking loose the surface rubble.”

Georgina Torbet
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
Hubble catches a baby star pulsating in a triple star system
This NASA Hubble Space Telescope image captures a triple-star star system.

This NASA Hubble Space Telescope image shows a triple-star star system. NASA, ESA, G. Duchene (Universite de Grenoble I); Image Processing: Gladys Kober (NASA/Catholic University of America)

A gorgeous new image from the Hubble Space Telescope shows a triple star system, where three stars are working in tandem to create a reflection nebula. The trio of stars are located 550 light-years away, and include one particular star, HP Tau, that is like a younger version of our sun and will eventually grow up to be a similar hydrogen-fueled star in millions of years' time.

Read more
Celebrate Hubble’s 34th birthday with this gorgeous nebula image
In celebration of the 34th anniversary of the launch of NASA’s legendary Hubble Space Telescope, astronomers took a snapshot of the Little Dumbbell Nebula, also known as Messier 76, or M76, located 3,400 light-years away in the northern circumpolar constellation Perseus. The name 'Little Dumbbell' comes from its shape that is a two-lobed structure of colorful, mottled, glowing gases resembling a balloon that’s been pinched around a middle waist. Like an inflating balloon, the lobes are expanding into space from a dying star seen as a white dot in the center. Blistering ultraviolet radiation from the super-hot star is causing the gases to glow. The red color is from nitrogen, and blue is from oxygen.

Tomorrow, April 24, marks the 34th anniversary of the launch of the Hubble Space Telescope. For more than three decades, this venerable old telescope has been peering out into space, observing stars, galaxies, and nebulae to understand more about the universe we live in. To celebrate this birthday, Hubble scientists have shared a new image showing the striking Little Dumbbell Nebula, also known as Messier 76, which is located 3,400 light-years away.

In celebration of the 34th anniversary of the launch of NASA’s legendary Hubble Space Telescope, astronomers took a snapshot of the Little Dumbbell Nebula, also known as Messier 76, or M76, located 3,400 light-years away in the northern circumpolar constellation Perseus. NASA, ESA, STScI

Read more
Hubble discovers over 1,000 new asteroids thanks to photobombing
This NASA/ESA Hubble Space Telescope image of the barred spiral galaxy UGC 12158 looks like someone took a white marking pen to it. In reality it is a combination of time exposures of a foreground asteroid moving through Hubble’s field of view, photobombing the observation of the galaxy. Several exposures of the galaxy were taken, which is evidenced by the dashed pattern.

The Hubble Space Telescope is most famous for taking images of far-off galaxies, but it is also useful for studying objects right here in our own solar system. Recently, researchers have gotten creative and found a way to use Hubble data to detect previously unknown asteroids that are mostly located in the main asteroid belt between Mars and Jupiter.

The researchers discovered an incredible 1,031 new asteroids, many of them small and difficult to detect with several hundred of them less than a kilometer in size. To identify the asteroids, the researchers combed through a total of 37,000 Hubble images taken over a 19-year time period, identifying the tell-tale trail of asteroids zipping past Hubble's camera.

Read more