Which planet is named for the Roman god of the underworld?

When this distant, icy world was discovered in 1930 by Clyde Tombaugh at the Lowell Observatory, its naming was put to a public vote. The winning suggestion came from an 11-year-old girl in Oxford, England, named Venetia Burney. She proposed the name of the Roman god of the underworld, reasoning that such a dark and remote world, far from the sun's warmth, was a fitting home for the deity who ruled over the dead. Her grandfather relayed the idea to astronomers, who unanimously approved.

The name was a perfect fit, not just for its mythological ties to a cold and gloomy realm, but for another clever reason. The first two letters, P-L, also served as a tribute to Percival Lowell, the astronomer who had predicted the existence of a "Planet X" beyond Neptune and had founded the very observatory where the discovery was made.

For decades, it was known as the ninth planet in our solar system. However, in 2006, the International Astronomical Union reclassified it as a "dwarf planet." This change in status was due to the discovery of other similar-sized objects in its orbital path. Despite the reclassification, its name remains a testament to a young girl's classical knowledge and the frigid, dark conditions at the edge of our solar system.