The Romans named the five planets closest to the Sun after their most important gods. These were the only planets that were bright enough for them to see.

Later, when telescopes were used, other planets were discovered. Astronomers decided to continue naming the planets after Roman Gods with one exception - Uranus. Uranus was named after the Greek god of the sky. According to myth, he was the father of Saturn and the grandfather of Jupiter.

Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. Uranus is similar in composition to Neptune, and both have different bulk chemical composition from that of the larger gas giants Jupiter and Saturn. For this reason, scientists often classify Uranus and Neptune as "ice giants" to distinguish them from the gas giants.

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