Astronomers have made a fascinating new discovery regarding the object known as Chiron, located in the region between Jupiter and Uranus. Recent observations indicate that Chiron is undergoing significant changes, including the formation of a ring system, visible in real time. Chiron, which has a unique jelly-donut shape and measures approximately 210 kilometers (130 miles) at its widest point, continues to intrigue scientists with its unusual characteristics.
This discovery was made possible by data gathered during a stellar occultation event on September 10, 2023, when Chiron briefly passed in front of a distant star. During this event, astronomers were able to observe not only the dimming of the star”s light caused by Chiron but also by several structures surrounding it. Chrystian Pereira from the National Observatory in Brazil explained, “When Chiron passed in front of a distant star, its light was dimmed not only by the main body but also by multiple structures surrounding it, allowing us to map this system in unprecedented detail.”
As a result of this event, researchers recorded three distinct signals corresponding to rings orbiting Chiron at distances of 273, 325, and 438 kilometers. It is believed that the two inner rings might be too close to Chiron to avoid being influenced by its gravitational pull. Additionally, the data unveiled a broader disk-like structure ranging from 200 to 800 kilometers, along with a newly identified faint signal at approximately 1,380 kilometers.
This latest study builds upon findings from earlier observations, including a 2023 analysis led by Amanda Sickafoose from the Planetary Science Institute. Both research teams concur that the ongoing observations indicate substantial changes occurring in the vicinity of Chiron. Notably, it seems that the disk structure may have formed recently, possibly around 2021, when Chiron experienced a brightening event that suggested material was being ejected, akin to comet behavior.
Pereira”s team remarked, “We are seeing the aftermath of a recent event. The material ejected by Chiron appears to be gradually settling in the object”s equatorial plane, being shaped by gravitational resonances and collisions, forming the rings we see today. It”s as if we”ve found the missing link, observing an intermediate stage in the formation of a ring system.”
Despite its relatively small size compared to planets, Chiron serves as a natural laboratory for understanding the dynamics of ring systems. Insights gained from studying Chiron may enhance our understanding of similar structures around other celestial bodies, such as Quaoar, Haumea, and Chariklo.
The findings from this observation have been published in The Astrophysical Journal Letters, presenting a unique opportunity to observe the formation of a ring system around a small celestial body. Researchers suggest that Chiron may provide an invaluable observational window into an intermediate phase of ring system evolution, potentially clarifying the processes behind the formation of ring systems around small bodies in the Solar System.
