You might also be interested in....

Space and time on Earth are regulated by the prime (Greenwich) meridian, 0'. Before the 1880s more than 25 prime meridians were in use, resulting in problems of global measurement that engaged geographers, astronomers and navigators.

Join a science journalist to explore the geology, geography and scenery of Icelandic volcanoes: from a world-changing 18th century eruption, to the latest ‘earth fires’ in 2014.