1/2 Historic view of Jupiter’s volcanic moon Io from New Horizons, at 2.3 million km. The red dot is glowing magma at the Tvashtar eruption site; the blue plume is fine dust particles lofted hundreds of km high and catching sunlight. A rare, detailed look at Io’s extreme activity from New Horizons’ Jupiter flyby. Io is the Solar System’s most volcanically active body, heated by intense tidal forces from Jupiter. This crescent image captures Tvashtar volcano in full eruption. The blue color comes from sunlight scattering off tiny ejected particles, much like blue smoke. Only the blue (~480 nm) & methane (~890 nm) channels of MVIC were usable: the red and near-IR filters overexposed on Io’s dayside because the instrument was designed for much dimmer Pluto. The high-resolution LORRI grayscale supplied the sharp detail that was then colorized with those two bands. Taken during New Horizons’ Jupiter flyby (closest approach 28 Feb. 2007; this view from the outbound leg on 1 March). The spacecraft obtained multiple views of Tvashtar’s large, structured plume, including the first-ever movie of an Io volcanic plume in motion. A key early result of the mission. At this range the LORRI resolution was roughly 11–12 km per pixel. Merging its sharp panchromatic data with the lower-resolution color information reveals both surface texture and the striking red-hot lava / blue dust contrast—an enduring image of Io’s violent geology.