A Closed Universe Click on image for full size (22K JPG) Courtesy of STScI

Eventually all of the matter in the Universe will collapse into a super dense state and possibly even collapse into an unimaginably massive black hole. Some theorize that the Universe could collapse into the same state that it began as and then blow up in another Big Bang. In this way the Universe would last forever but would continually go through these phases of expansion and contraction, Big Bang and Big Crunch and so on...