DART Mission Successfully Boops Dimorphos

On Monday, September 26, in front of a global audience, the Double Asteroid Redirection Test successfully hit the tiny, 160-meter asteroid Dimorphos.

Beth Johnson

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IMAGE: This illustration depicts NASA’s Double Asteroid Redirection Test (DART) spacecraft prior to impact at the Didymos binary asteroid system. CREDIT: NASA/Johns Hopkins APL/Steve Gribben

Congratulations to the DART mission teams! On Monday, September 26, at 23:14 UTC, in front of a global audience, the Double Asteroid Redirection Test successfully hit the tiny, 160-meter asteroid Dimorphos. Images streamed in from the onboard camera, DRACO, as the spacecraft approached the rocky surface, ending with a barely started image before going dark. But what a set of images they were up until then.

When the feed first went live, DART was still focused on Didymos, the larger of the binary asteroids, also referred to as the primary, as the spacecraft could not yet resolve the two bodies separately. Then, around T minus one hour, the autonomous system, or SMART Nav, needed to detect Didymoon, begin tracking the satellite, and lock onto it. During the SETI Institute’s live stream, DART Lead Investigator Andy Cheng announced that the spacecraft had achieved all of those goals and was on approach to the target. Moments later, Dimorphos was finally resolvable in the DRACO live feed.

Over the next 45 minutes, features on both Didymos and Dimorphos began to come into view, revealing that the pair are mostly like rubble pile asteroids similar to Ryugu and community favorite, Bennu. Boulders and craters and even a few flatter areas were clearly visible, and we expect that the images will be heavily analyzed over the coming weeks.

Due to the slight delay between sending the images and receiving them, about the scheduled time of the impact, Dimorphos began to fill the camera, eventually ending with that previously mentioned barely begun image. The spacecraft successfully hit the target, and everyone watching cheered to see it.

IMAGE: Asteroid moonlet Dimorphos as seen by the DART spacecraft 11 seconds before impact. DART’s on board DRACO imager captured this image from a distance of 42 miles (68 kilometers). This image was the last to contain all of Dimorphos in the field of view. Dimorphos is roughly 525 feet (160 meters) in length. Dimorphos’ north is toward the top of the image. CREDIT: NASA/Johns Hopkins APL

This mission was the first-ever planetary defense test, and NASA Administrator Bill Nelson said: At its core, DART represents an unprecedented success for planetary defense, but it is also a mission of unity with a real

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Beth Johnson

Planetary scientist, podcast host. Communication specialist for SETI Institute and Planetary Science Institute. Buy me a coffee: https://ko-fi.com/planetarypan