Site posts AP article. May Illuminate Missing Mass One of the strangest predictions of Einstein's theory of general relativity is that large amounts of matter can bend rays of light. That is to say, light, just like each of us, is subject to the laws of gravity. This strange effect of physics is allowing astronomers and astrophysicists to peer out to the very edges of our universe. The discoveries they are making are letting us study how galaxies formed in the earliest days of the universe and may ultimately allow us to predict our universe's fate.
Site describes history as well as applications of gravitational lensing.
Billions and billions of stars and galaxies gleam mysteriouslyin the night sky, inspiring philosophical thoughts. Because of their pull on our imagination, stars and their evolution have been the focus of much of astronomy. Yet almost equally compelling is the blackness between them. Site lays out the evidence, structure and current theories about dark matter in a readable way. According to a report published in January 1999, small ghost galaxies, dense clumps of dark matter whose stars have burned out, may lurk unseen throughout the universe.