Oh, what the heck. After posting the video earlier showing the Earth rotating around the sky, I might as well show you the original video, since it really is so beautiful. This time lapse shows the sky spinning over the Very Large Telescope observatory in Chile, one of the finest observatories in one of the darkest sites on the planet.
A couple of things I want to point out: at 1:10 into the video, you see the Milky Way rising majestically over the mountains, and you can see a faint, whitish glow stretching diagonally across the field of view, at an angle to the galaxy. That’s called the zodiacal light, and is caused by the reflection of sunlight by dust in the plane of our solar system. It’s probably due to eons of collisions grinding asteroids into dust; they tend to orbit the Sun in the same plane as the planets. It’s actually a disk of dust, but since we’re in it, we see it as a line across the sky. It’s pretty faint, and you need dark skies to spot it.
I also love the shots of the observatories shooting orange lasers out their domes (here’s a gorgeous hi-res photo of it). They’re fending off attacks by the Goa’uld, Ori, and Wraith using those to help counteract atmospheric distortion; the laser hits a layer of sodium atoms high in the atmosphere and causes them to glow. This creates a bright artificial star in the telescope’s view, which jiggles and wiggles as the atmosphere roils. The way the "star" moves can be counteracted by the telescope, sharpening up the image it makes. This tech, called adaptive optics, has revolutionized high-resolution ground-based astronomy. It has also given the VLT the ability to make incredibly sharp and gorgeous images; see for yourself.
Don’t forget to watch the companion video to this, too. It’ll change your perspective. Literally.
Video credit: Stéphane Guisard and Jose Francisco Salgado/ESO.