All About the Universe

The universe is composed of all visible and invisible matter and energy. It is approximated that the universe began 13.7 billion years ago, but like much of what we know about the vast expanse of space, we are not certain. While the universe is believed to be flat, it remains undecided whether or not it is infinite.
One of the most important recent discoveries is that ours is an expanded universe. Supported by the findings of Hubble, the observations of redshift helped us to make this discovery. Redshift refers to the process whereby all visible light bends towards the red end of the spectrum.
The origin of our universe is most popularly explained with the Big Bang theory. This idea states that everything around us was once condensed in a state of massive density and temperature. As space expands, so does our universe. Over the course of billions of years, the planets and galaxies we know of and the ones we don’t have been slowly moving outward.
While the expansion of our universe is widely accepted, the future of it is not. Respected scientists argue for both extremes. The universe may continue to expand forever, or it may eventually slow down enough to collapse. Read about more theories like the Big Crunch, Big Rip, Big Freeze and Heat Death of the Universe theory.
/SPACE.com