Outer planet
The outer planets are planets in the Solar System that are beyond the asteroid belt. The four planets; Jupiter, Saturn, Uranus and Neptune are gas giants. All four of these planets have planetary rings which are made up of dust and other particles.
Related pages
Moons of Jupiter - Rings of Jupiter
Moons of Saturn - Rings of Saturn
Moons of Uranus - Rings of Uranus
Moons of Neptune - Rings of Neptune
Inner planet
References
More reading
Scott W. Benson - Solar Power for Outer Planets Study (2007) - NASA Glenn Research Center
Trautman and Bethke - Human Outer Planet Exploration (2003) - NASA Langley Research Center and Princeton University
Other websites
Outer Planets Assessment Group (NASA) October 2011 OPAG Presentations
Planetary Science Decadal Survey Mission & Technology Studies
Dwayne Day - Exploration of the Outer Planets - U. S. Centennial of Flight Commission ~2003
Solar System planets