The most detailed telescope images yet of the asteroid Cleopatra – named after the ancient Egyptian queen – show its strange “dog bone” shape, and astronomers say their studies of it could yield clues about the solar system.
The latest observations of the asteroid, more than 125 million miles from Earth in the main asteroid belt between Mars and Jupiter, allowed scientists to more accurately measure the shape and mass of the unusual Cleopatra — and it turned out to be about a third lighter than expected, giving clues to its formation and formation.
said Frank Marches, chief planetary astronomer at the SETI Institute in California and lead author of New study Cleopatra published this month in the Journal of Astronomy and Astrophysics. “Cleopatra and other exotic asteroids are natural laboratories to challenge our knowledge of the solar system and make us think outside the box.”
Cleopatra was discovered in 1880 and derived its name from the original spelling of Cleopatra in the Greek alphabet. It is relatively large for an asteroid and has been observed by ground-based telescopes for decades to determine its orbit around the Sun. Its strange shape was only confirmed by radar about 10 years ago.
Latest images from the powerful European Southern Observatory very large telescope In northern Chile, it gives more detail about its peculiar shape – with two large lobes connected by a thick “neck”, so clearly resembling a bone.
Cleopatra lies approximately 160 miles away – the size of New Jersey – and weighs more than 3,300 trillion tons. It rotates about every five hours, and astronomers speculate that if it were spinning much faster, its lobes might spin apart.
Marches said that Cleopatra’s unusual shape is evidence of her formation. “It’s likely to be a loose-fitting asteroid, made from the rubble of ferrous material,” he said in an email.
Researchers believe it may have formed from the debris of a larger asteroid collision that occurred billions of years ago.
A team led by Marches announced in 2008 that their observations showed Cleopatra also had two small moons, each a few miles apart, and named it AlexHelios and CleoSelene after two sons of Egyptian queens.
It is not unusual for asteroids to have moons, or to form “binary systems” where two asteroids orbit each other. Marches said that at least 15 asteroids in the main belt are known to have moons, and more than 400 pairs of orbiting asteroids have been found.
Recent observations, he said, have allowed astronomers to make detailed measurements of the moons’ orbits around Cleopatra, indicating that they are ancient clumps of rubble emanating from the main asteroid — in other words, Cleopatra may have “born” children.