L.H.C (Large Hadron Collider) at CERN

A small portion of the Large Hadron Collider's 27 km tunnel. What you see in this picture are the two ultra-high vacuum tubes (10^-13 atm) inside which the particles beams (protons) are travelling, in opposite direction. They make the 26.659 km round trip (16.565 miles) about 11'245 times per second, at 99.99% of the speed of light. More information here.

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