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In the next few days, astronomers will decide whether Pluto is a planet or just an ice dwarf (a random rock floating in the universe). Pluto was discovered in 1930 by US astronomer, Clyde Tombaugh. Its status as a planet has been a topic of intense debate. Unlike other planets in the solar system, its orbit is slanting (not in the same horizontal plane with other planets’ orbiting paths) and is off center to the sun. It’s even smaller than the moon of the Earth!

Pluto moves from 30 to 50 times the Sun-Earth distance over its 248-year orbit. It has two moons in addition to Charon (the smaller object pictured here). The gravity on Pluto is about 6% of Earth’s; the surface temperature -233C.

Astronomers are gathering in the Czech capital, Prague, hoping to define exactly what counts as a planet. The International Astronomical Union (IAU) hopes to settle the question of Pluto, which was first spotted in 1930.

Experts are divided over whether Pluto - further away and considerably smaller than the eight other planets in our Solar System - deserves the title.

The stakes were raised when a bigger planet-type body, known as 2003 UB313, was discovered by a US astronomer.

Any decision to downgrade Pluto would send shockwaves through the scientific community, instantly outdate textbooks, and change how the basics of the Solar System are taught in schools.

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Since 1930, astronomers have become aware of a vast population of small, icy bodies resembling Pluto that orbit the Sun beyond Neptune, in a region called the Kuiper Belt.

This led some astronomers to argue that Pluto belonged with this population of “icy dwarfs”, not with the objects we call planets.

Allowances could once be made for Pluto on account of its size. At just 2,360km (1,467 miles) across, Pluto is significantly smaller than the other planets. But until recently, it was still the biggest known Kuiper Belt Object (KBO).

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One potential outcome of the meeting would be the promotion of 2003 UB313 - nicknamed Xena, after the TV warrior princess - into the exclusive club of “official” planets.

Some observers even believe the new definition of planet could cover other objects smaller than both Pluto and Xena. These include the KBOs Sedna and Quaoar.

Alternatively, Pluto’s status as the ninth planet could also be in danger if the experts decide it no longer makes the grade.

“It could mean the number of planets leaps to 20 or more, or it drops to eight. But I think most people would prefer not to drop Pluto altogether,” Mr Bond told the BBC News website.

Read more on: bbc.co.uk

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