The series ends with a look at the fate of the solar system.
Over the next four billion years, as a result of changes in the Sun. the Earth's oceans will boil, Saturn will lose its rings and one of Neptune's moons, Triton, will break apart to form a new ring system. Will the future of humankind depend on finding a solar system with a planet like Earth?
See today's choices.
(Digital widescreen)
CD: The Planets soundtrack is available now on BBC Music label
Reader Offer: buy the BBC hardback book The Planets, for only £17.99. inclusive of P&P; (rrp £19.99). To order call [number removed] or send a cheque, payable to RT Offers, to [address removed]
The end is nigh...: page 6