Maggie Aderin-Pocock explores our chances of finding life elsewhere in the universe. (R)
Watch from start
4/4 What may the digital future hold? Computers as tiny as the fluff in our pockets?
BBC Radio 4 Extra
1/2 Douglas Adams considers a global explosion in communication from a virtual world.
Andrea Sella returns to the Italian landscape of his childhood to see how it has changed.
BBC Radio 4
6/12 Looking at one of Fred Dibnah's favourite activities - restoring engines and chimneys. (R)
BBC Two except Scotland
3/3 A portrait of the beauty and surprising wildlife of Scotland's Cairngorms National Park. (R)
BBC Two Scotland only
Would you risk your life for a stranger?
BBC World Service