When Edwin Hubble discovered that objects exist outside of the Milky Way galaxy and that the universe is expanding, he shed new light on the field of astronomy. At the same time, he created a plethora of questions. How big is the universe? How old is it? Did it always exist?
Wherever astronomers looked, the universe was beautiful and strange. New classes of celestial objects were found that had been unimaginable just a few shorts years ago. Today, we are still trying to unravel the mysteries that we have encountered, and we still wonder what mysteries are yet to be discovered.
lifecycle of a star