There are rings in few planets in our solar system. A mission from European Space Agency’s has observed a dwarf planet in our own solar system and made a decisive contribution to the discovery of dense ring of material around it. The dwarf planet in known as Quaoar and it opens a mystery for astronomers to solve: why this material did not coalesced into small moon?
The ring was observed through a series of observations that took place between 2018 and 2021. A ground based telescope was used and astronomers watched Quaoar crossed in front of a succession of distant stars. Such event is known as occultation and observing the light can reveal whether intervening object has atmosphere or not. Quaoar is one of collection of small distant worlds known as trans- Neptunian objects (TNOS). The largest TNOs are Pluto and Eris. With the estimated radius 555 km the Quaoar is orbited y small moon called Weywot which is roughly 80 km in radius. Indeed, the first time the team attempted to observe an occultation with Cheops, which involved Pluto, the prediction was not quite accurate enough, and no occultation could be observed.
While the theoreticians get to work on how the Quaoar rings can survive, the Lucky Star project will continue to look at Quaoar and also other TNOs as they occult distant stars to measure their physical characteristics and see how many others also have ring systems.
