These three panels capture the breakup of the asteroid Dimorphos when it was deliberately hit by NASA’s 545-kilogram Double Asteroid Redirection Test (DART) mission spacecraft on 26 September 2022. The NASA/ESA Hubble Space Telescope had a ringside view of the space demolition derby. The top panel, taken 2 hours after impact, shows an ejecta cone amounting to an estimated 900 000 kilograms of dust.
The centre frame shows the dynamic interaction within the asteroid’s binary system that starts to distort the cone shape of the ejecta pattern about 17 hours after the smashup. The most prominent structures are rotating, pinwheel-shaped features. The pinwheel is tied to the gravitational pull of the companion asteroid, Didymos.
In the bottom frame Hubble next captures the debris being swept back into a comet-like tail by the pressure of sunlight on the tiny dust particles. This stretches out into a debris train where the lightest particles travel the fastest and farthest from the asteroid. The mystery is compounded when Hubble records the tail splitting in two for a few days.
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[Image Description: Three labelled images are stacked vertically. All three images show a bright white spot in the centre surrounded by an irregular cloud of blue that decreases in brightness with distance from the bright spot. The size and shape of the blue cloud are different in each image, as are the labels. In all three images the background is black and there are subtle diffraction spikes radiating from the bright spot.]