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Astronomers reveal sharp detail of asteroids located between Mars and Jupiter

The European Southern Observatory’s Very Large Telescope images 42 asteroids, most larger than 100 kilometres in size.
The European Southern Observatory’s Very Large Telescope images 42 asteroids, most larger than 100 kilometres in size. The European Southern Observatory’s Very Large Telescope images 42 asteroids, most larger than 100 kilometres in size.

A large group of asteroids have been revealed in sharp detail by astronomers, with a peculiar dog-bone shaped rock among the haul.

The powerful European Southern Observatory’s Very Large Telescope located in Chile has imaged 42 of the biggest objects in the asteroid belt found between Mars and Jupiter, the largest group to be observed in such detail.

Key characteristics such as their 3D shape or density have been largely unknown until now.

Asteroid Kleopatra
Asteroid Kleopatra The dog-bone shaped Kleopatra asteroid (ESO/Vernazza, Marchis et al/MISTRAL/PA) (ESO/Vernazza, Marchis et al./MIS)

Most of the rocks captured by the telescope are larger than 100 kilometres (62 miles) in size, with the two biggest – named Ceres and Vesta – measuring in at 940 and 520 kilometres (584 and 323 miles) in diameter respectively.

The tiniest of the crowd, Urania and Ausonia, measure in at about 90 kilometres (56 miles).

By reconstructing their shapes, scientists realised that the observed asteroids are split into two families.

Some, such as Hygiea and Ceres, are almost perfectly rounded spheres, while others have a more peculiar form, particularly Kleopatra which has an “elongated” shape, making it look like a dog-bone.

42 asteroids imaged by ESO’s VLT
42 asteroids imaged by ESO’s VLT 42 of the largest objects in the asteroid belt, located between Mars and Jupiter (ESO/M Kornmesser/Vernazza et al/MISTRAL/PA) (ESO/M. Kornmesser/Vernazza et al)

“Only three large main belt asteroids – Ceres, Vesta and Lutetia – have been imaged with a high level of detail so far, as they were visited by the space missions Dawn and Rosetta of Nasa and the European Space Agency, respectively,” said study lead Pierre Vernazza, from the Laboratoire d’Astrophysique de Marseille in France.

“Our ESO observations have provided sharp images for many more targets, 42 in total.”

Astronomers intend to image more asteroids in better quality once the new Extremely Large Telescope (ELT) is finished, though the kit will not be up and running until some time later this decade.