The universe began with a vast explosion that generated space and time, and created all the matter and energy in the universe. Exactly what triggered this sudden expansion remains a mystery.

If the observations of cosmic acceleration featured in the NOVA program "Runaway Universe" are correct, then the universe will probably continue to expand forever. Does this mean that the universe ...

Earth has been around for about 4.5 billion years. The universe has been around for about 13.8 billion years. Taken by themselves, those two numbers probably feel more or less the same. They're ...