The PIís Perspective: Encounter Planning Accelerates
Back in 2005 and 2006, when Plutoís second and third moons (Nix and Hydra) were discovered, searches by astronomers for still more moons didnít reveal any. So the accidental discovery of Plutoís fourth moon by the Hubble Space Telescope in mid-2011 (during a search for Plutonian rings) raised the possibility that the hazards in the Pluto system might be greater than previously anticipated. Those concerns were amplified when Hubble discovered a fifth moon in 2012. As a result of those discoveries, the New Horizons science and operations teams began to more carefully scrutinize the true level of hazards to our spacecraft at closest approach and devise mitigation strategies to make sure the encounter with Pluto would be successful.