Astronomers publish pictures of the 42 largest asteroids located between Mars and Jupiter | international | News

Thanks to the European Southern Observatory (ESO) VLT telescope in Chile, a team of astronomers has obtained images of 42 of the largest objects in the asteroid belt located between Mars and Jupiter.

According to experts, Such accurate images of such a large group of asteroids had never been obtained before.

The observations revealed a wide range of strange shapes, from spherical to some similar to dog bones, that help researchers trace the origins of asteroids in our solar system.

For ESO, the detailed images of these 42 objects constitute a breakthrough in asteroid exploration, thanks to ground-based telescopes, and contribute to answering fundamental questions about life or the universe.

So far, only three large belt asteroids, Ceres, Vesta, and Lutetia, have been obtained detailed images, which were visited by the Don and Rosetta space missions of NASA and the European Space Agency (ESA), respectively, explains Pierre Vernazza.

“Our observations at ESO provided sharp images of many objects, 42 in total,” adds Vernazza of the Marseille Astrophysics Laboratory, who led this study published in the Journal of Astronomy and Astrophysics.

Due to the small number of detailed asteroid observations, key features, such as their three-dimensional shape or density, have remained largely unknown.

Between 2017 and 2019, Vernazza and his team set out to fill that gap by conducting a comprehensive study of key objects in the asteroid belt, ESO said in a statement.

Most of the 42 objects in the sample are larger than 100 kilometres.

The team, which includes Spanish scientists, analyzed the two largest objects, Ceres and Vesta, estimated at 940 and 520 kilometers in diameter, while the two smallest asteroids were Urania and Osonia, which have a diameter of about 90 kilometers.

By reconstructing their shapes, the team discovered that the observed asteroids are essentially divided into two families.

Some are almost completely spherical, like Hygiea and Ceres, while others have a more unusual, “elongated” shape, with a “dog bone” asteroid named Cleopatra as the “undisputed protagonist,” ESO details.

By combining shapes with information about their masses, the team found that densities vary greatly across samples.

The four least dense asteroids studied, including Lamberta and Sylvia, have a density of about 1.3 grams per cubic centimeter, which is roughly the density of carbon.

Psyche and Kalliope have the highest density at 3.9 and 4.4 grams per cubic centimeter, respectively, which is higher than that of diamond (3.5 grams per cubic centimeter).

This large difference indicates that the composition of asteroids varies greatly, providing important clues to their origin.

Josef Hanos, from Karlova University explains: “Our observations provide strong evidence for a significant migration of these bodies since their formation. In short, the enormous diversity in composition can only be understood if the bodies originated in different regions of the solar system,” Prague

The results support the theory that less dense asteroids formed in remote areas outside Neptune’s orbit and moved to their current location. (I)