A few days ago I posted a video by José Francisco Salgado showing the sky over telescopes in Chile. He's just put up another one, this time showing the motion of the sky over several observatories: "Sidereal Motion".
Sidereal motion is literally the movement of the stars; the apparent rising and setting caused by the rotation of the Earth. You don't notice it second-by-second as you watch the sky, but over minutes and hours the inevitability of our planet's angular momentum makes itself known. José also has breathtaking images of observatories
as well as a website
linking to his work. He has an artist's eye for the heavens, and his creations are truly lovely.