2017-03-10 Fri

It’s not just Saturn that have rings! The rings of Uranus were discovered on March 10, 1977, by James L. Elliot, Edward W. Dunham, and Jessica Mink.

In just one year, nine distinct rings were identified. Two additional rings were discovered in 1986 in images taken by the Voyager 2 spacecraft, and two outer rings were found in 2003–2005 in Hubble Space Telescope photos.

These rings are extremely dark and they are probably composed of water ice with the addition of some dark radiation-processed organics. The majority of Uranus's rings are opaque and only a few kilometres wide. The rings of Uranus are thought to be relatively young, and not more than 600 million years old.

But do you know when Uranus was discovered?

In 1781 March William Herschel chanced upon an unknown object which at first he took to be a comet. But which was later recognized to be a new planet – the first planet ever discovered, since it was unknown to ancient astronomers on account of its faintness.

Herschel’s discovery doubled the known size of the Solar System overnight. It made him an international celebrity and ensured him the patronage of the King of England, George III. Here’s a stamp which was issued to commemorate the event of finding a new planet and honouring Herschel.