Hobbies And Interests
Planetary Objects
For a long time, both Neptune and Pluto were considered planets. Neptune was discovered in 1846 and Pluto was discovered in 1930. Both objects were considered planets until 2006, when astronomers, saying that Pluto had not "cleared the neighborhood" around its orbit, downgraded it to a dwarf planet, leaving only eight traditional planets.
Alternate Positions
Pluto and Neptune occasionally switch positions in relation to the sun, the only planetary objects to do so. Pluto, normally farther from the sun than Neptune, sometimes moves closer to the sun than Neptune. This occurred most recently from 1979 to 1999, and will occur next in the year 2227.
Proximate Orbits, But Not Distance
Compared with other planets, the orbits of Pluto and Neptune run close together. Their orbits cross on occasion, but because the orbits are on different planes, there is no chance of a collision. They never come within 1.2 billion miles of each other. For every three times Pluto orbits the sun, Neptune orbits only once.
Moons
Although Pluto is extremely small (estimated at 1,500 miles in diameter), like Neptune, it has moons. Pluto's largest moon is Charon, estimated to be over 700 miles in diameter. In 2005, astronomers discovered two smaller additional satellites circling Pluto, and named them Hydra and Nix. Neptune, a much larger planetary body, has 13 moons. The largest, Triton, measures over 1,600 miles across, making it larger than Pluto. Triton is estimated to be one of the coldest places in the universe, at around 400 degrees below zero.