Observations made by the Hubble Space Telescope have revealed that the Kuiper Belt object (148780) Altjira consists of not two but three bodies. This discovery supports one of the theories for the formation of the Solar System.
There are many three-body systems in the Universe, including the closest star to the Sun, Alpha Centauri. Some astronomers have long suspected that the Kuiper belt is no exception — and the Hubble telescope has helped confirm that assumption.
The discovery was made in the process of studying the trans-Neptunian object Altjira, located at a distance of 6.65 billion kilometers from Earth. Until recently, it was thought to be a double object, one with a diameter of about 250 kilometers and the other with a diameter of 220 kilometers.
However, while analyzing data collected over 17 years of observations by the Hubble telescope and Keck Observatory, scientists suspected that the inner object was actually two bodies that were so close together that they could not be distinguished at such a great distance.
“Over time, we noticed a change in the orientation of the outer object’s orbit, indicating that the inner object was either highly elongated or actually composed of two separate bodies,” said Darin Ragozzine, one of the study’s co-authors.
The results of the subsequent simulation showed that the triple system was the best option. The discovery has important implications for confirming the theory of the formation of Kuiper belt objects. According to it, the three small bodies did not form as a result of a collision in the “densely populated” Kuiper belt, but formed as a single system directly from the gravitational collapse of matter in a disk of matter around the young Sun about 4.5 billion years ago. This means that Altjira may be far from the only triple system in the Kuiper belt.
Earlier we reported on how astronomers discovered analogs of the Kuiper belt in other stars.
According to Phys.org
