Light and Dark (2013)

The central premise of this series is that what the human eye can see is only a fraction of the vast amount of matter and energy that exists out in the Universe: our best estimate is that more than 99% of all the stuff that’s out there is hidden in the dark. So how do we know it’s there?
E1 Light: Professor Jim Al-Khalili tells the story of how we used light to reveal the cosmos.
E2 Dark: Prof Jim Al-Khalili investigates the 99 per cent of the cosmos that is hidden in the dark.
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