Pluto in size of Charon and Pluto has prompted some astronomers to call it a double dwarf planet. The system is also unusual among planetary systems in that each is tidally locked to the other, which means that Pluto and Charon always have the same hemisphere facing each other. From any position on either body, the other is always at the same position in the sky, or always obscured. This also means that the rotation period of each is equal to the time it takes the entire system to rotate around its barycenter. In 2007, observations by the Gemini Observatory of
Exploration of Pluto launched in 2030, marking the 100th anniversary of Pluto's discovery, and spending 7-8 years traveling to the Pluto system. The Fusion-Enabled Pluto Orbiter and Lander was a 2017 phase I report funded by the NASA Innovative Advanced Concepts (NIAC) program. The report, written by principal investigator Stephanie Thomas of Princeton Satellite Systems, Inc., describes a Direct Fusion Drive (DFD) mission to Pluto. A fusion reactor would be used to send a 1000 kg orbiter and lander to the Pluto system in only four years (more than twice as fast as "New Horizons"). Global Aerospace Corporation presented a Pluto lander concept