Astronomy Picture of the Day

Explanation: Scroll right and watch the universe evolve. Above is a computer simulation depicting the evolution of our entire universe. On the far left is a slice of the universe soon after the Big Bang - over 10 billion years ago. As time progresses toward the right, the initially smooth universe can be seen becoming more and more clumpy. The vertex near the far right marks the present day. The largest slice of the universe actually surveyed is simulated to the vertex's right. This artificial universe, called a Hubble Volume, was designed to mimic what humanity might see were we to have powerful enough telescopes. By comparing different computer simulations to reality, we might be able to better tell what kind of universe we live in.