March 1 () –
The Hubble Space Telescope recorded the partial disintegration of the asteroid Dimorphos when it was deliberately struck by the half-ton DART mission craft on September 26, 2022.
the hubble movie -disseminated now by NASA- begins 1.3 hours before impact. The first post-impact snapshot is 2 hours after the event. The debris moves away from the asteroid in a straight line, at a speed greater than 6 km/h (enough to escape the asteroid’s gravitational attraction and not fall on it again). The ejecta form a hollow cone with long, fibrous filaments.
About 17 hours after impact, the debris pattern entered a second phase. Dynamic interaction within the binary began to distort the conical shape of the ejecta pattern. The most prominent structures are rotating pinwheel-shaped elements. The pinwheel is tied to the gravitational pull of the companion asteroid, Didymos.
Next, Hubble captures the debris being blown back into a comet-like tail by the pressure of sunlight on the tiny dust particles. This tail extends to form a debris train in which the lightest particles travel the fastest and farthest from the asteroid. The mystery thickens later, when Hubble records how the tail splits in two for a few days.
