Pluto Facts

Pluto Facts
Astronomers, scientists who study the stars, have now said that Pluto is not a real planet but a dwarf planet. This is because it behaves more like a planet than an asteroid or a moon, but only in some ways. So in our Solar System the number of true planets now stand at 8. Scientists often refer to Pluto and its moon, Charon as a double-planet system.
Interesting Pluto Facts:
A dwarf planet like Pluto orbits the Sun and has enough mass to become a sphere (shaped like a smooth ball).
Pluto can't be called a planet because it doesn't have enough mass to attract passing asteroids or meteors into itself. Pluto doesn't behave like a moon and orbit a bigger planet.
Pluto and Charon are both made up of rock and ice. They are thought to have been captured together by the Sun from the Kuiper belt beyond Pluto.
Dwarf planets are smaller than the Solar System's smallest planet, Mercury. So far scientists have recorded 3 dwarf planets in our Solar System. They are Pluto, Eris and Ceres.
Scientists believe there may be hundreds of dwarf planets in our Solar System.
Pluto has an orbit around the Sun that is like a giant oval (we call this elliptical). It travels at an average speed of 10,444 mph (16,809 km/h).
Pluto's average distance from the Sun is 3,665 million miles (5,899 million km). At this distance the Sun would look like a bright star.
Pluto's year, which is the time taken to complete one orbit around the Sun, is 248 Earth years. For 20 years of its orbit Pluto is closer to the Sun than Neptune.
A day on Pluto is 6.4 Earth days which means that it rotates slower than Earth.
Pluto's diameter is 1,430 miles (2,302 km) across which means that it is two thirds smaller than Earth's Moon.
The Earth is 456 times more massive than Pluto.
Pluto's volume is also much smaller than that of Earth. 167 Pluto's would fit into the space of one Earth.
The Average surface temperature of Pluto is -378oF (- 228oC).
Pluto has one moon called Charon which is half the size of Pluto. The distance between them is 12, 200 miles (19, 640 km).
Charon takes the same time to rotate on its axis as Pluto does. This means Pluto's moon never rises and sets like our Moon and always has the same side facing Pluto.
Pluto rotates on its axis from east to west. Only Pluto, Venus and Uranus out of all the objects in the Solar System do this.
Unlike the others planets of the Outer Solar system, Pluto has no rings.
In 2005 two new moons were discovered orbiting Pluto. They are called Nix and Hydra. In 2011 and 2012 two more tiny moons were discovered.
When Pluto moves closer to the Sun the frozen Methane and Nitrogen on its surface creates a thin atmosphere. As the planet moves further away from the Sun, the atmosphere that hasn't escaped into space is refrozen on the surface.
The Space probe, New Horizons was launched January 19, 2006 and on the way to Pluto it flew past Jupiter on February 28, 2007. It will arrive at Pluto in 2015. It will go on into the Kuiper Belt and finish its mission in 2026.
The New Horizons space probe carries a special piece of scientific equipment, a dust detector. It was designed and built by students.

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