With all the talk of exoplanets, we sometimes forget how little we know about the planets and moons in our own solar system. For example, 25 years ago on August 25, 1989, the Voyager 2 spacecraft shined a light on the system as it headed towards the edges of the solar system and beyond. The image above of Neptune's moon Triton was
restored recently by the NASA-funded Lunar and Planetary Institute and turned into a film. Even back then Voyager 2 could see Triton was an active planet with atmospheric plumes. Triton is a little larger than Pluto and most likely started the same as Pluto but was caught in the orbit of Neptune. We should see more of Pluto next July when the New Horizons spacecraft visits the dwarf planet.
