[ad_1]
September 9 (UPI) – The European Southern Observatory’s very large telescope has provided astronomers with their best view to date of Cleopatra, the “dog bone” asteroid.
Using the high-resolution images captured by the VLT, astronomers were able to precisely constrain the shape and mass of the asteroid.
The latest research – detailed in two articles, published Thursday in the journal Astronomy & Astrophysics – may offer clues to the origin and evolution of Cleopatra and her two moons.
“Cleopatra is truly a unique body in our solar system,” said Franck Marchis, who led the investigation, in a statement.
“Science is making a lot of progress by studying weird outliers. I think Kleopatra is one of them and understanding this complex and multiple asteroid system can help us learn more about our solar system. “said Marchis, senior planetary astronomer at SETI. Institute in Mountain View, California.
Cleopatra’s bony form, two lobes connected by a thick neck, was first revealed by radar observations captured 20 years ago.
In 2008, Marchis and his research partners spotted Cleopatra’s two moons. They named the couple AlexHelios and CleoSelene, after two of the Egyptian queen’s three children.
The researchers characterize the dimensions of Cleopatra using images captured by the VLT’s SPHERE instrument between 2017 and 2019. As Cleopatra spins, astronomers were able to capture images of the asteroid from different angles.
The high-resolution images allowed scientists to build an accurate 3D model of the asteroid, revealing its outlines and volume. Research also confirmed that one of Cleopatra’s lobes was larger than the other.
In addition to limiting the size and shape of Cleopatra, the SPHERE data also showed earlier estimates of the orbits of the asteroid’s two moons to be in error.
“This had to be resolved,” said Miroslav Brož, researcher at Charles University in Prague, Czech Republic. “Because if the orbits of the moons were wrong, everything was wrong, including Cleopatra’s mass.”
Scientists used the new observations and the new model to estimate the influence of Cleopatra’s gravity on lunar orbits.
The calculations, in turn, allowed the researchers to determine the mass of the asteroid, revealing that it was 35% less than first approximations.
Kleopatra is believed to be made up of various metals, but its low density suggests that it is very porous and likely a conglomerate of rocks and rubble.
Because the rubble pile spins at such a high speed – almost fast enough for the entire structure to fall apart – scientists suspect that even minor impacts would be enough to loosen the materials, which is probably why Kleopatra got it. its two moons.
As revealing as the images from the VLT have proven, astronomers are eager to capture even higher definition images using the extremely large telescope, which is expected to capture “first light” in 2026.
“I can’t wait to point the ELT at Cleopatra, see if there are more moons, and refine their orbits to detect small changes,” Marchis said.
[ad_2]
Source link