Pluto was discovered in 1930 and its largest moon Charon (they’re almost better thought of as a double-world system) in 1978. The even smaller Nyx, Hydra, and S/2001 P 1 (provisional name) are all from the last decade. Of all the worlds so far covered, the least is known about Pluto, given its tremendous distance from Earth. It is like Ceres in that it’s classified as a dwarf planet.
Modern Exploration of Pluto and Charon:
- New Horizons (2015?) – NASA flyby mission, the only planned mission to the distant reaches of the solar system. It was launched well over six years ago, and is still about 9 AU from Pluto. It carries seven science instruments, which were tested out during the Jupiter gravity assist maneuver. 2015 will be a good year for planetary science, between New Horizons reaching the Pluto-Charon system and Dawn reaching Ceres.