Ian Johnston, who you'll recognise from the programme, explains the science at the heart of the Geek's schemes:
You might get a lot of thrust, but it's at the expense of control. Fireworks, moonshots - and Geeks - rely on the same rocket science.
Content last updated: 22/09/2006
Two members of the Life team go in search of penguins in their natural environment. See what they find on Deception Island.
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