or the beautiful Horsehead Nebula. The red light you see behind the horse's head is from interstellar HYDROGEN gas, that has been LIT UP, like a gas lamp, by very energetic ultraviolet radiation from nearby stars. The dark head of the horse is caused by very THICK interstellar dust BLOCKING the light from behind.

First SlidePrevious SlideHomeInformation About The PresentationNext SlideLast Slide