32 Important Facts About Pluto

Last updated on May 4th, 2019

Pluto is a dwarf and not a full-sized planet. With these 32 facts about Pluto (the first Kuiper Belt object to be discovered) let us learn more about it.

1. Discovery: Pluto was discovered in 1930 by Clyde Tombaugh.

Clyde W. Tombaugh. Image credit – Wikipedia

2. Reclassification: Pluto was reclassified as a Dwarf planet in 2006 by the International Astronomical Union. It is called a dwarf planet because of its small size and lack of enough capability to clear debris and object out of its path around the sun (Order of the planets from the SunMercuryVenusEarth, MarsJupiterSaturnUranusNeptune, and Pluto (the dwarf planet)).

3. In 2003, a new object beyond Pluto was discovered by an astronomer — Michael Brown. After the discovery of this new object – Eris – astronomers pondered upon the characteristics that make an object in the sky “a planet”. And they came to a conclusion that Pluto shall be classified as a Dwarf planet henceforth.

4. Called an asteroid: on September 7, 2006, Pluto was assigned the asteroid number 134340 by the Minor Planet Center.

5. Pluto’s gravity: if one weighed 100 pounds on Earth, they would weigh only 7 pounds on Pluto – that’s how weak the planet’s gravity is, as compared to that of the Earth.

Pluto by NASA
This image of Pluto was taken on July 13, 2015, when the spacecraft was 476,000 miles (768,000 kilometers) from the surface. CREDIT: NASA/APL/SwRI

6. Research: the Hubble Space Telescope is playing a key role in providing interesting and important information about Pluto.

7. Far away: the distance between Pluto and the Sun is 40 times the distance between the Earth and the Sun.

8. Kuiper Belt: the orbit of Pluto lies in the Kuiper Belt. There are many other small icy worlds in this region, which are also known as ‘transneptunian objects’ or ‘Kuiper Belt objects.’

Table showing length of the day on the planets

PlanetLength of Day
Mercury1408 hours
Venus5832 hours
Earth 24 hours
Mars25 hours
Jupiter10 hours
Saturn11 hours
Uranus17 hours
Neptune16 hours

9. Five moons: Pluto has five moons – Charon, Nix, Hydra, Kerberos, and Styx.

10. Pluto vs Earth’s Moon: Pluto is 2/3rd the diameter of Earth’s moon and its mass is 1/6th the mass of Earth’s moon.

11. Round the Sun: Pluto takes 248 Earth years to revolve around the Sun. This is the longest orbit time among other planets.

12. Elliptical orbit: Pluto has an elliptical orbit and hence when it is closest to the Sun, its ice changes to gaseous form and forms a thin atmosphere over the planet. Charon, the largest moon of Pluto, takes around 6.4 Earth days to complete a revolution around the planet.

13. Day’s length: one day on Pluto is also 6.4 Earth days.

14. One of the moons – Charon: Charon is tidally locked to Pluto, meaning that its same side faces Pluto all the while both the bodies revolve in the outer space.

15. Distance from the Sun: Pluto can be as far as 49.3 AU from the Sun in its elliptical orbit where it takes 248 years to complete a revolution around the Sun.

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