Rings aren’t exclusive to giant planets: Chariklo, an icy body only about 250 kilometres across—shorter than Tasmania is long—carries two narrow rings, and Webb observations suggest they are changing
Recent observations from the James Webb Space Telescope suggest that the rings surrounding the small icy body Chariklo are changing in opacity. While the findings indicate potential physical changes, researchers note that light interaction with small grains could also explain the data.
Why it matters
This discovery challenges previous assumptions that ring systems are exclusive to giant planets and provides new insights into the dynamics of small solar system bodies.
Webb data indicate Chariklo's dense inner ring grew more opaque while its tenuous outer ring faded, though wavelength-dependent grain behaviour remains an alternative explanation.
Published September 14, 2026 · How we edit
Chariklo is an unlikely place to look for a ring system. The icy Centaur is about 250 kilometres across, smaller than the roughly 286-kilometre length given for Tasmania in a Tasmanian government fact sheet . Yet two narrow rings orbit well beyond its surface.
A paper published in Science Advances on 9 September 2026 reports that those rings may be changing over timescales measured in years. A Webb occultation observed in 2022 found the dense inner ring about 50 per cent more opaque than earlier measurements, while the outer ring appeared about 60 per cent less opaque than it did in 2017. Their radial positions were essentially unchanged.
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