10. Neptune - Voyager's Last Planet

Voyager 2, launched in 1977, has already passed by the giant planets Jupiter, Saturn and Uranus, all of which have provided plenty of surprises. Voyager has now passed Neptune, sending back remarkable new information about the outermost planet. In this programme, Patrick Moore is joined by Dr Garry Hunt and other experts from the American team to summarise what has been discovered about this lonely, remote world.