... Observing springtime deep-sky objects with a large telescope . ... In the Large Hadron Collider, two streams of protons travel in opposite directions at near light-speed before they collide with each other. Does this mean that the two particle streams are moving at nearly twice the speed of light relative to each other? ... Get instant access to subscriber content on Astronomy.com! ... If you are already registered on Astronomy.com, please log in below. ...