Alan Stern, principal investigator for the New Horizon mission, reveals his biggest surprise so far as the probe closes in on Pluto. (Recorded 12 July 2015.)
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Putting Pluto’s geology on the map
To help mission scientists understand the diversity of Pluto’s terrain and to piece together how the dwarf planet’s surface has formed and evolved over time, NASA’s New Horizons mission scientists have started constructing geological maps. The base map for this interpretation is a mosaic of 12 images obtained by the spacecraft’s Long Range Reconnaissance Imager (LORRI).

Pluto’s close-up, now in colour
This enhanced colour mosaic combines some of the sharpest views of Pluto that NASA’s New Horizons spacecraft obtained during its 14 July flyby, revealing features smaller than half a city block on the dwarf planet’s surface. The wide variety of cratered, mountainous and glacial terrains seen here gives scientists and the public alike a breathtaking, super-high-resolution colour window into Pluto’s geology.