Hubble captures rocks detached from the asteroid ‘Dimorphos’ after the impact of the DART spacecraft

2023-07-20 17:33:40

MADRID, 20 Jul. (EUROPA PRESS) –

Astronomers using the space telescope Hubble They have discovered rocks that possibly broke off from the asteroid ‘Dimorphos’ when the DART spacecraft intentionally impacted its surface at approximately 22,500 km/has reported by ESA.

DART intentionally collided with ‘Dimorphos’ on September 26, 2022, slightly altering the trajectory of its orbit around the largest asteroid, ‘Didymos’.

The 37 ejected rocks range in size from 1 meter to 6.7 meters in diameter, according to Hubble photometry.. The rocks are moving away from the asteroid at about one kilometer per hour.

The total mass of these detected rocks is approximately 0.1% of the mass of ‘Dimorphos’. These rocks are some of the faintest objects ever imaged in the Solar System.

These images open up a new dimension for studying the consequences of the DART experiment using the European Space Agency’s upcoming Hera mission, which is scheduled to launch in 2024. The spacecraft will carry out a detailed post-impact study of the target asteroid ‘Dimorphos’.

Hera will turn this large-scale experiment into a well-understood and repeatable planetary defense technique that could one day be used in reality.

The ESA says it believes the rocks are most likely not broken fragments of the asteroid caused by the impact., but were already scattered across the surface of the asteroid, as evidenced by the last image taken by the DART spacecraft just two seconds before the collision, when it was just 11 kilometers from the surface.

The science team that observed these rocks with Hubble estimates that the impact shook about 2% of the rocks on the asteroid’s surface. Although Hubble’s observations of rocks also provide an estimate of the size of the DART impact crater, Hera will eventually determine the actual size of the crater.

Dimorphos may have formed long ago from material ejected into space by the largest asteroid, Didymos. The main body may have rotated too fast or may have lost material after a tangential collision with another object, among other scenarios.

The ejected material formed a ring that gravitationally condensed to form ‘Dimorphos’. This makes it a flying pile of rocky debris loosely held together by gravity. Therefore, its interior is probably not solid, but more like a bunch of grapes in structure.

The astronomers say it’s unclear how the rocks were kicked up from the asteroid’s surface and could be part of an ejection plume that was imaged by Hubble and other observatories, or a seismic wave from the impact could have resonated through the asteroid, shaking debris off the surface.