Pluto is a dwarf planet that lies in the Kuiper Belt. It’s an area full of icy bodies and other dwarf planets at the edge of our solar system.  Pluto is the biggest object in this region and so some call it King of the Kuiper Belt.”

A dwarf planet is a medium-sized world roughly 2000km wide that orbits a star. In our solar system , 5 known bodies qualify as dwarf planets. They include Pluto. Asteroids are smaller than dwarf planets. These rocky chunks mainly circular between Jupiter and Mars , some do however have elongated orbits near earth.

Comets however are big , dusty snowballs that venture in towards the sun from the chilly reservoirs of icy bodies  , the Kuiper Belt beyond Neptune and the more distant Oort cloud. As they approach the sun and heat up , Comets sprout fuzzy asppriachntmospheres of gas and dust and sometimes a long tail.

The Kuiper Belt

At distances of about 30 and 50 astronomical units from the sun( an astronomical unit is  a unit of measurement equal to 149.6 million kilometers , the mean distance from gbe centre of the earth to the centre of the sun) .


Some interesting facts:

Pluto is only about half the width of the United States. Charon is about half the size of Pluto. Charon is the largest moon compared to the body it orbits (whether planet or dwarf planet) of any moon in the solar system.

Almost all the planets travel around the sun in nearly perfect circles. But Pluto does not. It takes an oval-shaped path with the sun nowhere near its center. What’s more, its path is quite tilted from the nice, orderly plane where all the planets orbit.(Mercury has a slightly lop-sided orbit, although not nearly so much as Pluto’s.)

Compared to most of the planets and their moons, the whole Pluto-Charon system is tipped on its side. Like the planets, Pluto’s spin axis stays pointed in the same direction as it orbits the sun. But unlike all planets except Uranus, Pluto is tipped on its side. The planets’ axes of rotation stand more or less upright from the plane of their orbits.

If you lived on Pluto, you’d have to live 248 Earth years to celebrate your first birthday in Pluto-years.

If you lived on Pluto, you would see Charon from only one side of the planet. Charon’s orbit around Pluto takes about six and one-half Earth days. Pluto’s day (that is, one complete rotation) takes exactly the same amount of time. So, Charon always “hovers” over the same spot on Pluto’s surface, and the same side of Charon always faces Pluto.

At Pluto’s current distance from the sun, the temperature on its surface is about 240 degrees below zero Celsius  (-400° F). It can get even colder as it moves farther from the sun. 

From Pluto, the sun looks like just a bright dot in the sky, the brightest star visible. The light from the sun is as bright on Pluto as the light from the full Moon is on Earth.

If you weigh 100 pounds on Earth, you would weigh only 7 pounds on Pluto!

On January 19, 2006, NASA launched a robot spacecraft on the mission called New Horizons. The spacecraft arrived at Pluto in July 2015, and will continue to study other objects in the Kuiper Belt from about 2018 to 2022.

Pluto is still the largest object in the Kuiper Belt despite being two thirds the size of earth’s moon , it has a thin atmosphere (which can freeze when it is furthest from the sun). It’s surface is covered in methane and water ice and had a reddish colour due to the presence of carbon-based chemicals called tholins. 

It does have a complex system of satellites. Charon , and the far smaller Styx, Nix, Kerberos and Hydra.

Pluto was discovered on this day in 1930! Happy 87th Earth birthday Pluto!


Image credits: NASA & google