Pluto - The Little Dwarf Planet That Could (Or Couldn’t?)
Overview
Pluto, the ninth planet in our solar system (or is it?), has had a bit of a rollercoaster ride over the years. Discovered in 1930, Pluto was considered a full-fledged planet for over seven decades. But in 2006, after much controversy and debate, the International Astronomical Union (IAU) demoted Pluto to the status of a “dwarf planet.”
Appearance
Pluto is relatively small, measuring just 1,473 miles in diameter - smaller than the United States! It has five known moons and a reddish-brown color, which some have likened to a “dirty snowball.” But don’t let its small size fool you - Pluto has a heart of gold (or at least, nitrogen, methane, and carbon monoxide).
Discovery
Pluto was discovered by American astronomer Clyde Tombaugh in 1930 while he was working at the Lowell Observatory in Flagstaff, Arizona. Tombaugh was actually looking for “Planet X,” a hypothetical planet beyond Neptune that was thought to be causing gravitational disturbances in the outer solar system. While Pluto ended up not being the elusive Planet X, Tombaugh’s discovery was still groundbreaking.
Controversy
Poor Pluto has been at the center of quite a bit of controversy over the years. Some scientists believed that it shouldn’t be considered a planet at all, arguing that it didn’t meet all three criteria of being a true planet (orbiting the sun, having a spherical shape, and clearing the neighborhood of its orbit of debris). Others felt that Pluto was simply the ninth planet in our solar system, plain and simple.
Ultimately, the IAU voted to reclassify Pluto as a “dwarf planet” in 2006, a decision that was met with both support and protest. Some felt that Pluto had been unfairly stripped of its planet status, while others felt that the new classification was scientifically sound.
Trivia
- Pluto is named after the Roman god of the underworld, not the lovable Disney dog.
- Because Pluto is so far from the sun, one year on Pluto (the time it takes to complete one orbit around the sun) is equivalent to almost 248 Earth years.
- NASA’s New Horizons spacecraft flew by Pluto in 2015, giving us our first up-close look at this little dwarf planet.
- Despite its small size, Pluto has more moons than any other planet in our solar system.
Conclusion
In the end, whether or not you consider Pluto to be a “true” planet is up for debate. But one thing is for sure - this little dwarf planet has captured our imaginations and sparked our curiosity about the outer reaches of our solar system. Plus, who wouldn’t love a planet named after the god of the underworld?