Take a good look at the latest picture of Pluto because it shows the face of the dwarf planet that will not be seen during next week's historic flyby. The US space agency's New Horizons probe was less than 2.5 million km from the diminutive world on Saturday and closing in fast. Come Tuesday, it will be grabbing shots from an altitude of just 12,500km. But the newly published image, showing Pluto's "spots", is of the hemisphere that will soon rotate out of view. It will not be seen again until after New Horizons has gone behind the 2,300km-wide dwarf,...