Why do some of the stars not move in this time-lapse video?

This beautiful time-lapse video was taken from the world's highest revolving restaurant atop a mountain in the Swiss Alps. It shows the stately procession of stars as they move through the night sky. So why are some stars not moving? » 4/11/12 10:52am 4/11/12 10:52am

A Haunting Photograph of the Fall Equinox From Space

The September equinox occurred this morning at 5:05 am EDT, marking the official start of Fall for those of us in the Northern Hemisphere. Twice a year, during the latter halves of March and September, every person on Earth experiences the effects of an equinox in the form of a 12-hour day followed by a 12-hour night. » 9/23/11 10:59am 9/23/11 10:59am