picture of the asteroid Kleopatra obtained from the Keck II telescope. To the left of the "raw" image, right after processing. In the latter image are clearly visible in the form of highly elongated and Kleopatra, top right, the two small bright spots marked 1 and 2. These are the two small satellites with a diameter of about 8 km.
French and U.S. researchers have investigated the asteroid is named after the Egyptian queen. It is not a piece of rock, but is made of materials together by gravity. The two fragments, detached in an impact, as have been baptized the twins had to be Marco Antonio.
by the famous Egyptian queen is not in common only the name but also two twin sons. The asteroid Cleopatra it has two small moons, probably fragments that have broken off after a collision 100 million years ago. The discovery is reported by the University of Berkeley and in an article published in the journal Icarus and is about a group of French and American astronomers are also ready to give an appropriate name to the two small satellites: Cleoselene and Alexhelios , the names of the twins had to Cleopatra by Mark Antony, Cleopatra Selene II and Alexander Helios.
Images of the asteroid Kleopatra radar data obtained from different rotational phases. Its shape is impressive, it resembles in all respects to a "dog bone".
Thanks to observations with other telescopes, including Keck II in Hawaii, as well as determine the presence and the orbits of the two moons were also confirmed the peculiar form of Cleopatra, like a big dog bone. The presence of satellites has also enabled us to estimate the mass density of the asteroid, surprisingly been below expectations: it is not therefore a single compact, as expected from asteroids of this size, As a collection of fragments held together by mutual gravitational attraction.
For Franck Marchis, an astronomer at the University of Berkekey involved in the research, just this structure explains the two moons and the bone shape. According to the reconstruction worked with his colleagues, about 100 million years ago, the collision with another asteroid did Cleopatra quickly turn on itself because of its compactness and low rotation of this vortex, over the next million years assumed an elongated shape, throwing out several pieces including the current 'two moons.
The group of astronomers are now continuing the observations looking for other large asteroids with satellites, so to be able to calculate the density and determine its internal structure. This is a search that may have important consequences because the more you will like Cleopatra, more adjustments will be made to existing models for the formation of rocky bodies that populate our solar system.
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