In 2006, the International Astronomical Union (IAU), the organization responsible for classifying celestial bodies, reclassified Pluto as a “dwarf planet.”
This was because the definition of a planet at that time required that it must clear its orbit of other debris, and Pluto was found to share its orbit with other objects in the Kuiper Belt, a region of small icy bodies beyond Neptune.
So, Pluto was reclassified as a dwarf planet, a new classification for celestial bodies that are spherical in shape but have not cleared their orbit of other debris.
How many moons does pluto have?
Pluto has five moons, named Charon, Styx, Nix, Kerberos, and Hydra.
How long would it take to get to pluto?
The travel time to Pluto depends on the spacecraft and its speed. Currently, the fastest spacecraft to visit Pluto was NASA’s New Horizons, which launched in 2006 and took 9.5 years to reach Pluto.
Other factors that can affect travel time include the distance from Earth to Pluto (which varies due to their different orbits), the speed of the spacecraft, and the trajectory taken by the spacecraft. But for a rough estimate, a journey to Pluto could take anywhere from 9 to 15 years or more using current technology.
How long does it take Pluto to orbit the sun?
Pluto takes 248.09 Earth years to complete one orbit around the sun. This means that a year on Pluto is 248.09 Earth years long.
What is the color of Pluto?
Pluto is predominantly reddish-brown in color. The reddish hue is thought to be due to the presence of tholins, complex organic molecules that form in Pluto’s atmosphere when ultraviolet light from the sun interacts with nitrogen and methane.
These tholins then fall to the surface and give it the reddish color. In addition to the reddish color, there are also areas of bright white ice, thought to be made of frozen nitrogen and carbon monoxide, and dark regions thought to be made of hydrocarbons.
Planets and dwarf planets
Here is a comparison of planets and dwarf planets:
| Property | Planets | Dwarf Planets |
|---|---|---|
| Definition | A celestial body that orbits the sun and is spherical in shape, and has cleared its orbit of other debris. | A celestial body that is spherical in shape, orbits the sun, but has not cleared its orbit of other debris. |
| Number | 8 (pre-2006) | 5 (currently recognized) |
| Examples | Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune (pre-2006) | Ceres, Pluto, Eris, Haumea, Makemake |
| Size | Ranges from small rocky bodies (e.g., Mercury) to gas giants (e.g., Jupiter) | Generally smaller than planets |
Note: In 2006, the International Astronomical Union reclassified Pluto as a dwarf planet, reducing the number of planets in the solar system from 9 to 8.
