The world will be photographed again on July 19. The picture will be a very small picture, reminiscent of this image taken at a distance of about 3.7 billion miles away, from the Voyager in 1990. The pale blue dot at the centre of that image is our planet, which inspired astronomer Carl Sagan to write "Pale Blue Dot". Sagan narrated on this 90 second video, an animation by Joel Somerfield.
