An international group of astronomers may be planning to add three planets to the solar system.
No, it's not science fiction. It's a draft resolution set to be presented to the International Astronomers meeting Wednesday in Prague.
On the agenda is a universal definition of a planet.
If the resolution is passed next week, Pluto's largest moon and two other heavenly bodies would join the nine existing planets.
One, the asteroid Ceres, had been considered a planet in the 1800s, but was demoted. Some astronomers have suggested Pluto should be demoted as well.
But the current proposal would end that debate, by defining a planet as any round object that orbits the sun and meets a certain size.
The astronomers will hold two brainstorming sessions before voting on a resolution.