How many planets do we have now?

When many of us grew up, there were nine planets in the Solar System. It was like a fixed point in our brains. As kids, memorizing this list was an early right of passage of nerd pride: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. read more

For those of us who believe dwarf planets should be counted as a subclass of planets, the latest status is that our solar system now has 13 planets: four terrestrial planets, four jovian planets, and five dwarf planets. read more

Other dwarf planets include Ceres, Haumea, Makemake, and Eris. With an atmosphere, stark surface features, and at least five moons, Pluto is the most complex dwarf planet we know, and one of the most surprising solar system planets. read more

"We are sampling the galaxy to understand how many planets there are and how far out we have to search in order to find potentially habitable planets like Earth," Natalie Batalha, the Kepler mission scientist at NASA's Ames Research Center, said in the announcement. read more