Cosmic Perspectives from Amid the Stars:
Astronomy Blog

"The cosmos is within us. We are made of star-stuff. We are a way for the universe to know itself." -Carl Sagan When Carl Sagan delivered his famous quote on his TV series “Cosmos,” he wasn’t just being poetic; he was making a literal statement. We are literally made of material that comes from stars. But how? Let’s dive into the meaning of this famous quote.

There is an estimated septillion stars in the observable universe (that’s a one followed by 24 zeroes). They’re everywhere you look and come in all sorts of varieties. Every star is unique, but they all follow a similar life cycle. A star is a ball of gas, usually hydrogen and helium, that is so dense, it can fuse that hydrogen into heavier elements, creating energy. Depending on its size and rate of fusion, a star can live anywhere from a few million years to trillions of