“Normally,” rings around a planet are created from the remnants of meteors, moons, and even left over from the planet’s own formation. These remnants that make up the rings are maintained by the gravitational pull of the planet. Bodies in space are not expected to suddenly learn how to develop their own rings; however, this is not the case in NASA’s latest discovery.
Uncovering the mysterious development of a new structure forming in space
For decades, researchers have been studying the formation of rings around planets like Saturn in an attempt to understand what criteria have to be met in order to make and sustain these rings. It was believed that rings were unique to Saturn, but over the years, with the constant development of technology and equipment, scientists found that rings are found on other objects too.
The planets were all gas giants with deep gravitational wells, which made researchers suspect that these had to be the requirements to achieve a formation of rings around a planet. This discovery has revealed that even small bodies in space can acquire rings without having to be a gas giant or having a huge amount of gravitational potential.
A body in space that is not a gas giant has rings around it, and scientists uncover how they formed
The discovery was made by observing the Centaur’s celestial objects. A small body that orbits between Neptune and Jupiter is named 2060 Chiron, which has qualities of both a comet and an asteroid. An observational campaign in 2023 utilized a technique called stellar occultation to understand Chiron and its environment. Stellar occultation is a technique where a body is observed when it passes in front of a star and temporarily blocks it, so that the planet is easier to observe and get accurate measurements.
When the data came back after being thoroughly analyzed, it revealed that not only does Chiron have rings, but it is actively making them. Astronomers detected several features on Chiron :
Faint probable moon dust: located much further out, around 1,380km from the center of Chiron
A “broad, disc-like structure” radiating outward between 200 and 800km from the center of Chiron, and within this structure, three rings.
Outer ring (C3): located on the edge of the dense region with a radius of 438km, it is the outermost dense concentration
Middle ring (C2): visible separation from the inner ring, it is distinctly positioned within the disc,c C1, 325km from the center, and not connected inner ring.
Inner ring (C1): sharpest gradient with a high-density material located closest to the nucleus,eus located 273km from the center.
Chiron’s history and the likelihood of the rings around it forming
Chiron was originally discovered in 1977 by Charles Kowal, and it was the first identified Centaur. At first, it was classified as an asteroid due to its distance and lack of comet characteristics and movements. It was later observed to experience a coma, which is a cloud of gas and dust surrounding the nucleus. It exhibited both characteristics of a comet as well as an asteroid, leading to researchers naming it two different names: asteroid 2060 Chiron and comet 95P/Chiron.
Researchers unveiled that the material on Chiron most likely blasted off when underground ice suddenly vaporized and that some of these remnants settled into orbit. The theory is that over time, the debris flattened and its shape turned into a disc, and collision between particles smoothed the motion of the material. It was also theorized that the gravitational pull was defining the material deposition into ring-like bands.
What is the significance of this discovery, and what comes next?
This is the first time that scientists are observing a body that can create its own rings; this discovery will give them more insight into how the other planets’ rings might’ve come about in their early formation stages. Chiron’s rings are developing quite fast, allowing researchers to witness how rings can evolve, form, and maybe even disappear. The lesson that is taken away from NASA and all the discoveries that the institution makes is: always expect the unexpected, and that anything can change in space.