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WHAT TO SEE
Before its reclassification, Pluto was the furthest planet from the Sun. From the surface of Pluto, the Sun is so tiny it looks like a bright star in the sky. Pluto is very small, only half the size of Earth's moon.
This remote ball of ice remains a bit of a mystery. The first probe due to visit Pluto won't arrive until July 2015.
Light and dark regions
Telescope images show light and dark regions.
The lighter areas are probably ices of nitrogen, methane, ethane and carbon dioxide. The darker regions may be a result of photochemical reactions driven by cosmic rays, but their exact nature is unknown.
Further investigation will be one of the first tasks for any visitor to Pluto.
LOCAL HISTORY
Pluto was discovered by accident in 1930 by Clyde William Tombaugh. Astronomers had begun to search for a new planet beyond Neptune after calculations of this planet's orbit predicted the existence of a large mass beyond it.
 Find out more about Pluto's larger neighbour, Neptune
The sums later proved to be wrong, but not before astronomers had started their search for a new planet. And before the error in the calculations had been realised, Pluto had already been discovered.
Pluto was named after the Greek god of the underworld, possibly because it is so far from the Sun. The name was suggested by an 11 year old school girl from Oxfordshire.
Planet or dwarf?
Astronomers have disagreed about Pluto in the past, arguing that it should not be called a planet because of its small size and distant location. To resolve the issue, the IAU have confirmed a new scientific definition. To be called a planet, an object must be in orbit round the Sun, it must be large enough that it takes on a nearly round shape, and its orbit must be clear of other planets. For 20 out of every 248 years, Pluto's orbit overlaps with Neptune's orbit, so Pluto is no longer classifiable as a planet. It joins Ceres and Eris in the newly formed category 'dwarf planets'.
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TRAVEL INFORMATION
Journey time · 8 Earth years
1 Plutonian year · 248 Earth years
Time lag · 7.93 hours
Before you leave
Make sure that you wrap up warm. At a chilly -230ºC, Pluto is one of the coldest places in the Solar System.
You might want to make sure you time your trip for the summer months. During the winter, it is so cold that even the atmosphere freezes!
When you arrive
While approaching Pluto, keep an eye out for the unusual feature of its rotation. It rotates in the opposite direction to all the planets.
Pluto's moons
Pluto has one large moon, Charon, and two tiny moons called Nix and Hydra.
There are many moons in the Solar System that spin around on their axis at the same rate as they orbit their planet. Our Moon is like this, which is why we always see the same side of the Moon when we look at it from Earth.
Pluto is the only celestial body that spins at the same rate as its moon orbits. So you can only see Charon from one side of Pluto.
SPOTTING PLUTO FROM THE EARTH
Pluto can't be seen from Earth with the naked eye. It's possible (though tricky) to spot it through a telescope, if you know exactly where to look.
Even powerful Earth-based telescopes aren't strong enough to see Pluto's dark surface in detail. The view from the Hubble telescope shows less detail than you can can see on the Moon from Earth.
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