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British astronomer William Herschel had discovered solar system's seventh planet — Uranus, 237 years ago, on March 13, 1781. However, the discovery was one of its kind as the ice giant was repeatedly mistaken as a star. After all, as Albert Einstein said: "Anyone who has never made a mistake has never tried anything new."

Herschel was surveying stars of at least magnitude eight (the sequence starts with the brightest being magnitude -1 and then goes to 0, 1, 2, 3, 4, 5, 6,7, 8, 9...so on, according to stargazing.net) in 1781 when he stumbled up a very faint object. To his surprise, the barely visible object moved in front of the fixed stars — which indicated that it was much closer to the earth. Herschel, initially thought that he had discovered a comet and presented his observation to Royal Society, the oldest national scientific institution in the world.

After other astronomers studied it, it was concluded it is actually a planet orbiting our Sun.

Astronomers also learned that Uranus, which is the third-largest planet in our solar system, was spotted as early as 1690, according to earthsky.org, but was always dismissed as a star.

Some interesting facts about Uranus:

1. The planet takes 17 hours and 14 minutes to complete one rotation [Rotation can be defined as the circular movement of an object around a center/axis]. It rotates in a retrograde direction, which is opposite to the way Earth and most other planets rotate.

2. For revolution around the Sun, Uranus takes 84 Earth years [our planet takes only 365 days].

3. Uranus has 27 known moons, which are named after characters created by William Shakespeare and Alexander Pope. Some of them are Oberon, Titania, Miranda, Cordelia, and Umbriel.

4. Uranus has 13 known rings and they are believed to be made of debris from moon or moons, which were broken probably after collisions with objects such as a comet or asteroid

5. Uranus was visited only by one planetary mission — Voyager 2. In 1986, it flew by the planet at a distance of 81,500 km and captured pictures of its moons and rings.