Some of the most defining features of the planets in our solar system include Mars's redness, Jupiter's giant red spot, and Saturn's magnificent rings. The others don't have much to make them stand out from the rest. But we are discovering new things about them as time passes.
Recently, astronomers have seen a warm glow on Uranus's rings, which are very difficult to see as it is. These were detected using some very powerful telescopes which observe infrared wavelengths and electromagnetic radiation.
The new images taken by the Atacama Large Millimeter/submillimeter Array (ALMA) and the Very Large Telescope (VLT) allowed the team for the first time to measure the temperature of the rings: a cool 77 Kelvin, or 77 degrees above absolute zero -- the boiling temperature of liquid nitrogen and equivalent to 320 degrees below zero Fahrenheit.
The observations also confirm that Uranus's brightest and densest ring, called the epsilon ring, differs from the other known ring systems within our solar system, in particular the spectacularly beautiful rings of Saturn.
(Image credit: UC Berkeley image by Edward Molter and Imke de Pater)