Earth and beyond

our solar system

what if...?

Mercury

Venus

Earth

Mars

Asteroids

Jupiter

Saturn

Uranus

Neptune

Pluto

comets and meteors

Pluto

Pluto - Unique facts:

Pluto was discovered in1930 by a young astronomer called Clyde Tombaugh.

It is the only planet not to have been visited by a spacecraft. It has an unusual orbit around the Sun. The orbit shape is the most squashed (most elliptical) of all the planets. At one stage, Pluto crosses inside the orbit of Neptune, making Neptune the furthermost planet from the Sun for about 20 years.

This last happened between 1979 and 1999, but now Pluto is back again as the most distant planet.

9th nearest planet to the Sun. In other words the furthest.

Smallest planet

Diameter

Mass

Distance from Sun

Orbital time

Rotational period

Major moons

2,274 km

1.27 x 10²² kg

5,913.5 million km

248 Earth years

6.4 Earth days

Image showing our solar system and all it's planets orbital paths

Pluto was the Roman god of the underworld. Perhaps the planet received this name because, being so far from the Sun, it is always cold and dark.

Pluto is a bit small to qualify as a proper planet. Some people think that Pluto could be an escaped moon of Neptune, or a large asteroid. Pluto isn't alone out there in the depths of the solar system, it has a large moon called Charon: no not Sharon!

How does that

compare with the Earth?

Diameter		0.18 the diameter of the Earth
Mass		0.0021 the mass of the Earth
Distance from Sun		39.5 the distance of the Earth from the Sun
Orbit time		Pluto takes 248.6 Earth years to orbit the Sun