Cluster of rock and ice a sweltering 77K, we're told

Astronomers have measured the temperature of one of Uranus’s rings, dubbed Epsilon, for the first time.

Uranus, our Solar System's far-flung icy electric-blue-colored ball, is circled by 13 rings.

They were only recently discovered, as early as 1977, due to their faintness.

In 2017, fresh images of the mysterious planet were captured by the Atacama Large Millimeter Array and Very Large Telescope, both in Chile, that highlighted the thermal energy, or lack thereof, in its rings.

A paper to be published this month in the Astrophysical Journal (here’s the free arXiv version) describes a study of those images, and concludes Epsilon is a chilly 77 kelvin, about the same temperature as the boiling point of liquid nitrogen.

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