James Webb's near-infrared observations revealed contrasting changes in the double ring system of the centaur Chariklo. The inner ring has become significantly denser — likely it is constantly replenished with material. The outer ring, on the contrary, is almost invisible in infrared light, whereas it was previously clearly visible. This could mean loss of material, i.e. the outer ring may be temporary, or its transparency varies with wavelength, just as cloud visibility changes at different sunsets. Such complexity of small body rings had not been observed before.
Using the most powerful space telescope, James Webb, astronomers peeked into the cosmic dressing room and saw how the rings of asteroid Chariklo are changing. By observing a passage in front of a star—when the body casts a mini-eclipse on a distant star, a standard method for finding planets around other stars—they discerned: the inner ring grew denser, as if more partners had joined the dance, while the outer almost dissolved into darkness.
Both rings are made of cosmic dust and ice, but they behave differently. The inner one is constantly replenished by ejections from Chariklo's surface—energetic steps that keep the dance alive. The outer, conversely, thins out, yielding to the starlight. This suggests that such ring systems are not an eternal show, but rather a fleeting performance. Chariklo, the centaur hybrid, turns out to be far more changeable than previously thought: its rings live and vanish faster than those of planets.
🎯 From Earth, Chariklo's rings are invisible to any telescope—they reveal themselves only through brief 'winks' of stars as the asteroid passes in front of them.