For 10 points, name this dwarf planet that forms a binary system with Charon, formerly the ninth planet.
One moon of this body was nearly named Vulcan due to an endorsement from William Shatner. This object was the most notable nearby object discovered by the use of a blink comparator. The existence of this object was inferred from observations made by Percival Lowell, and its name was suggested by the 11-year-old Venetia Burney, though it was actually discovered by Clyde Tombaugh. This object, the destination of the New Horizons probe, exhibits at 2:3 orbital resonance with Neptune, whose orbit it occasionally intersects when viewed from above the ecliptic. For 10 points, name this dwarf planet that forms a binary system with Charon, formerly the ninth planet.
One moon of this body was nearly named Vulcan due to an endorsement from William Shatner.
Pluto