Pluto as seen by the Hubble Space Telescope
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Nasa mission about to take first Pluto pictures

The US space agency's mission to Pluto is about to take its first pictures of the mysterious icy world.

The encounter is being billed as the last great exploration of our Solar System.

NASA's New Horizons probe set off nine years ago - before Pluto was demoted to a dwarf planet.

Rebecca Morelle reports.

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