The new observations were made using the Very Large Telescope of the Southern European Observatory in Chile, and the sharp sharpness of the images has helped scientists learn more about the mass and 3D shape of the asteroid. This information could shed more light on how the asteroid and its two moons formed.
The closest to Earth, Kleopatra is 200 million miles away.
Two studies that include observations published Thursday in the journal Astronomy & Astrophysics. One focused on the shape of the asteroid, while the other looked more closely at the mass of the asteroid as well as its moons.
“Kleopatra is truly a unique body in our solar system,” Franck Marchis, lead author of the 3D shape study, said in a statement. “Science is advancing a lot thanks to the study of strange extreme values. I think Kleopatra is one of those and understanding this multiple asteroid complex can help us learn more about our solar system.”
Marchis is a senior planetary astronomer at the SETI Institute in Mountain View, California, and is also affiliated with the Laboratoire d’Astrophysique in Marseille, France.
The asteroid is unusually located in the main asteroid belt between Mars and Jupiter and orbits the sun. Kleopatra’s radar observations 20 years ago revealed its shape: two lobes connected by a thick neck.
Marchis and his team discovered two small moons orbiting the asteroid in 2008 and were named AlexHelios and CleoSelene, in honor of Cleopatra’s children.
The instruments of the Very Large Telescope captured images of Kleopatra between 2017 and 2019. This allowed astronomers to see Kleopatra and its moons from different angles for a better understanding of its 3D shape. Scientists determined that one of the asteroid’s lobes is larger than the other. And it is about 269 kilometers long, which is about half the length of the English Channel.
The researchers also used the observations to better understand the orbits of Kleopatra’s two moons.
“This had to be resolved,” Miroslav Brož, author of the study of the moons and researcher at the Astronomical Institute of Charles University in the Czech Republic, said in a statement. “Because if the orbits of the moons were wrong, everything would go wrong, including Kleopatra’s mass.”
The findings of the latest study of the moon allowed researchers to determine how the asteroid’s gravity influences the movements of the moons. Astronomers were also able to calculate the mass of the asteroid, which is 35% lower than previously estimated.
The density of Kleopatra is less than half that of iron, which means that although the asteroid is likely to have a metallic composition, it is probably a porous asteroid with debris batteries. Debris stack asteroids are a cluster of space rocks held together by gravity and usually form after the pieces accumulate again after a massive impact, as if a larger asteroid were hit by another rock. spatial.
The fact that Kleopatra is an asteroid with debris could also explain why it has two moons. The asteroid rotates so fast that it is possible for the material to rise from the surface if Kleopatra is struck or struck by something, even something small. Pieces could have broken Kleopatra in the past, forming the moons AlexHelios and CleoSelene.
The Extremely Large Telescope (ELT) of the Southern European Observatory, which is expected to begin making observations from Chile in 2027, could provide even more details about the strange asteroid.
“I can’t wait to point the ELT towards Kleopatra, to see if there are more moons and to refine their orbits to detect small changes,” Marchis said.