The solar system would have 12 planets instead of nine, if a draft resolution presented on Wednesday to the International Astronomical Union (IAU) gets approved.

The definition of a planet has been increasingly challenged in recent years as large celestial bodies were found in the outskirts of our solar system.

The debate intensified when astronomer Michael Brown, of the California Institute of Technology, announced the discovery of a celestial object larger than Pluto in July 2005. He nicknamed the new find "Xena".

The IAU kicked off a 12-day meeting in Prague on Monday to come up with a universal definition of what qualifies as a planet.

Many scientists at the meeting argued that Pluto should be excluded from the family of the solar system planets. They believe Pluto is odd in many ways: it is smaller than Earth's moon, and with its elongated orbit and funky orbital plane, it is different from traditional planets.

However, a special panel in the IAU has reached agreement on how to define a planet, reaffirming the status of the controversial Pluto. The new definition, if passed, would increase the number of planets in the solar system from nine to 12.

The new lineup would include 2003 UB313, the farthest-known object in the solar system, nicknamed Xena; Pluto's largest moon, Charon; and the asteroid Ceres, which was a regarded as a planet in the 1800s before it was demoted.

Source: Xinhua