At a press conference shortly before NASA’s Double Asteroid Redirection (DART) spacecraft. crashed into an asteroid reporter tried to understand what would happen when a pile of metal and electronics crashed into a pile of debris left over from the birth of the solar system. “Let us feel this battle between our spacecraft and this rock,” asked the journalist of the scientist from the Laboratory of Applied Physics.
“Spaceship loses,” quipped APL’s Nancy Chabot.
The most amazing thing about this loss is that we experienced it in real time, as the last image from DART’s onboard camera cropped out after only a small part was transmitted to Earth.
The details of the spacecraft’s crash landing/collision with the Dimorphos asteroid had to be captured on cameras located a little further away from the impact site. Many of them have already become available, so we have collected them and described a little of what you can see.
The closest cameras we had were aboard LICIACube, a Cubesat that was carried into space aboard DART and then separated weeks before impact. The LICIACube had two built-in cameras (Luke and Leia), one took wide-field images and the other could focus better on details. The Italian space agency, which managed the LICIACube mission, did not say which camera took which image, but released several of them, including a distant view of the collision, close-ups taken shortly afterward, and an animation showing the sudden illumination after the collision of scattered material into space.
For those unsure, the collision itself did not produce enough light to be visible in these images. Instead, the debris ejected from the DART asteroid reflected much more sunlight than the asteroid could on its own.
The illumination was large enough for ground-based telescopes to pick up the illumination as well; in several cases, their operators posted images online as soon as they became available. Both I found show the Didymos/Dimorphos system moving peacefully past the background stars from Earth’s perspective (most of the light reflected from the much larger Didymos). Suddenly, the object brightens significantly, and the debris gradually moves away from the asteroids.
There are two big differences between the images. One image taken by the ATLAS project, which is based in Hawaii but has telescopes there, in South America and South Africa – the collision was visible only from the latter. In his image, the asteroid moves from right to left against the background of stars.
ATLAS Observations of the DART Spacecraft Collision with Didymas! pic.twitter.com/26IKwB9VSo
— ATLAS Project (@fallingstarIfA) September 27, 2022
In contrast, data from the Las Cumbres Observatory telescope in South Africa show that the Didymos system moves across the star field in the opposite orientation. But it also has some pretty important information: timestamps for each exposure in the animation, making it clear that most of the action took place over the course of about half an hour.
Animation (accelerated 500 times) from one of the @LCO_Global1-meter telescope @SAAO South Africa shows the consequences #DARTMission hit Dimorphos (still no threat to Earth… Long straight line is camera artefact) pic.twitter.com/StYWtLArgG
— Tim Lister (@astrosnapper) September 27, 2022
ESA also produced a video of the collision covering the same time period posted it online.