Many people are still upset that Pluto was demoted from being a planet. But definitions of various celestial objects are fairly fluid. So whether it is an asteroid or moon or planet is up for debate.
The Hubble Space Telescope has spotted clouds and storms on the solar system's ice giants.
A body at least twice as massive as the Earth smashing into Uranus could have made it lopsided, shows research.
New experimental results on methane may help us to uncover whether Uranus really is the coldest planet.
The Voyager space probes sent back some amazing images of the planets in the outer Solar System, and they're still talking to Earth every day via Australia's tracking station.
How a bunch of pebbles could have created Jupiter, Saturn, Neptune and Uranus.
Space scientists have a busy decade ahead with plans to visit Jupiter, Mars, Mercury and other interplanetary bodies all on the cards.