Facts About Pluto


If ever Pluto could narrate its own story, it would go something like this…

“There I was, wandering quietly in the sea of cosmos, humming to the sound of my own whistle until they found me. I knew nothing then: neither the light nor the show, but to my own surprise, I was referred as a planet. An identity is what a long lost craves for! They gave me one, named me Pluto, bright lights and photographs, mention among the greats of Earth, recognition and remembrance in every little one’s mind is what I received. They loved me the most and I loved it. For 75 years it went on, the glory and the fame, till they stripped me off my planetary status; I wasn’t big enough for the ride, they said. A dwarf I am now, planet they call me still, as if it’ll hurt less. Distant and cold they have left me along the corners of the solar system they call it their own. From rags to riches to rags again, they know lesser about me still, but curious they are more, than before. Rise I will to the riches again, is the promise I make; New Horizons (read facts) will open up a new world for them, more than what they can take.

Read on to know more about what is known about me: Pluto – The Former Planet”

Fast Facts

Discovered By: Clyde Tombaugh
Discovered In: 1930
Distance From Sun: 5,906,440,628 km
Distance From Earth: 4284.7 x 106 km (Minimum) and 7528.0 x 106 km (Maximum)
Mean Radius: 1,151 km
Equitorial Circumference: 7,231.9 km
Volume: 6,387,259,783 km3
Mass: 1.3 x 1022 kg
Density: 2.050 g/cm3
Surface Area: 16,647,940 km2
Surface Gravity: 0.66 m/s2
Length of Day: -6.387 Earth days (retrograde)/-153.29280 hours (retrograde)
Length of Year (Orbital Period): 247.92065 Earth years/90553.02 Earth days
Number of Moons: 3
Number of Provisional Moons: 1
Average Orbit Velocity: 16,809 km/h
Orbit Inclination: 17.14 ˚
Orbit Circumference: 36,529,978,039 km
Temperature: -233 ˚C (Maximum) and -223 °C (Minimum)

Interesting And Fun Facts About Pluto

    • From 2006, Pluto began to be classified as a dwarf planet. However, earlier, for a period of almost 75 years, it was classified as a planet, 9th from the Sun, after Neptune.
    • Apart from being a dwarf planet, Pluto is also a member of icy objects that orbit around the Kuiper Belt, which is a disc shaped region beyond the orbit of Neptune.
    • Pluto is the much smaller than any of the eight official planets in our solar system. In fact, it is even smaller than Earth’s Moon, being only about of two-third its diameter.
    • Because of being so small in size with very low density, Pluto’s mass is only one-sixth of Earth’s Moon.
    • Since Pluto’s density, is only 2.3 g/cm3, it is believed that the planet’s composition is combination of rock and water ice: 70% and 30% respectively. Plus, the bright areas of the planet are believed to be covered with nitrogen in iced form along with smaller proportions of solidified methane, ethane and carbon monoxide.
    • Pluto’s mass is more (by a factor of 20) than that of its cousin Ceres, another dwarf planet that resides in the asteroid belt between Mars and Jupiter.
    • It takes Pluto 248 years to complete an orbit around the sun. Because of its elliptical orbit, Pluto goes as far as 49.3 Astronomical Units (one Astronomical Unit equals the mean distance between Earth and the Sun: 150 million km) from the sun.
    • 1979 to 1999 was the golden period for scientists studying this distant planet as for these 20 years, Pluto was closest to the Sun. In fact, in the year 1989, Pluto came as close as 29.7 AU, being actually closer to the Sun than Neptune.
    • It was Pluto’s elliptical orbit because of which it was so near. To the very least, it after 230 years that Pluto will come so close to the Sun for a period of another 20 years, beating Neptune.
    • Science believes that when Pluto comes this close to Sun, the ice on its surface melts and rises to temporarily form a thin layer of atmosphere.
    • Pluto’s gravity is only about 6% of Earth’s. Due to this, the atmosphere that forms on Pluto extends to higher altitude when compared to Earth’s atmosphere. However, when Pluto moves farther and farther from the sun, the bulk of its atmosphere is believed to freeze over.
    • Pluto has rather a large moon, Charon, which is almost half its size. Discovered back in 1978, Charon is so big that the duo is referred to as a double dwarf planet system. Charon is only 19,640 km away from Pluto and was discovered by American astronomers James Christy and Robert Harrington.
    • In the year 1994, when Pluto was closest to Earth (about 30 AU), The Hubble Space Telescope photographed Pluto and Charon; images revealed that Pluto is reddish in appearance whereas Charon, greyer, signifying that both entities have different surface compositions.
    • The most interesting thing about Charon is that, when seen from Pluto, it neither sets nor rises, but lingers over the same spot, showing the same face to the dwarf planet. This concept is known as Tidal Locking.
    • Two more moons, albeit tiny, were discovered by scientists through The Hubble Space Telescope when preparing for the New Horizons Mission in the year 2005. These two moons, named Nix and Hydra, are two to three times farther away from Pluto than Charon.
    • The most fascinating thing about the moons of Pluto is that they are named after mythological figures linked with the underworld. Charon – the river Styx boatman who ferries souls in the underworld. Nix – mother of Charon and goddess of darkness. Hydra – nine headed serpent guarding the underworld.
    • Pluto too is named after the Roman god of Underworld and there’s an interesting theory that goes behind it. In 1930 when Pluto was discovered, it was an 11 year old girl, Venetia Burney of England who suggested to her grandfather that the new planet be named after the Roman god of underworld. The grandfather too took to the name and forwarded it to the Lowell Observatory and was selected.
    • Like the planets Venus and Uranus, Pluto too rotates backward, from east to west. This concept of backward rotation is known as Retrograde Rotation. If one were able to set foot on Pluto, they will see Sun rising from the west and setting in the east.
    • Research is inconclusive as to whether or not Pluto has a magnetic field. Because of its miniature size and slow rotation, experts believe that it may have very little or no magnetic field.
    • In January 2006, a spacecraft named New Horizons was launched which, if everything goes well, is expected to reach Pluto in 2015.
    • It is impossible to spot Pluto with the naked eye. And even when seen with a telescope (unless it’s not Hubble or lesser equivalent), Pluto will appear as a star.
    • 134340 – This is the number assigned to Pluto in the minor planet catalogue.