If not, you really REALLY ought to. Amazing stuff. I can barely get my head round how people are clever enough to piece together all those clues, let alone how people were plotting the future 2 millennia ago.
It's basically about a shipwreck artefact that was found in 1900. Scientists have been trying to work out what it does for 100 years. Basically it plots the movement of the universe to the exact day. Awesome stuff.
It's on iPlayer until Sunday.