The Thin Blue Line

Image for The Thin Blue LineNot currently available on BBC iPlayer

Duration: 1 hour

Professor Brian Cox reveals how something as flimsy as an envelope of gas - an atmosphere - can create some of the most wondrous sights in the solar system. He takes a ride in an English Electric Lightning and flies 18 km up to the top of earth's atmosphere, where he sees the darkness of space above and the thin blue line of our atmosphere below. In the Namib desert in south-west Africa, he tells the story of Mercury. This tiny planet was stripped naked of its early atmosphere and is fully exposed to the ferocity of space.

Against the stunning backdrop of the glaciers of Alaska, Brian reveals his fourth wonder: Saturn's moon Titan, shrouded by a murky, thick atmosphere. He reveals that below the clouds lies a magical world. Titan is the only place beyond earth where we've found liquid pooling on the surface in vast lakes, as big as the Caspian Sea, but the lakes of Titan are filled with a mysterious liquid, and are quite unlike anything on earth.

  • Photo: Brian prepares for take off

    Photo: Brian prepares for take off

    Brian Cox sitting in a Lightening Jet preparing to fly 18KM above the surface of the earth.

  • Photo: NASA control room

    Photo: NASA control room

    Inside the NASA control room where all communication with the Mars Rovers takes place.

  • Photo: The Matanuska Glacier

    Photo: The Matanuska Glacier

    Brian sits on the Matanuska Glacier in Alaska as he prepares to reveal his fourth wonder.

  • Explore the Solar System

    Explore the Solar System

    Watch video clips from classic BBC television programmes about the Solar System. The videos cover topics including the planets, moons and astronauts from series such as The Planets, The Sky at Night and Horizon.

    Learn more about the Solar System with clips from the BBC archive


Brian Cox
Chris Holt
Series Producer
Danielle Peck
Executive Producer
Andrew Cohen


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