Carl Sagan: "The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of star stuff.

Carl Sagan: "The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of star stuff.

. But the water, the hydrogen, that’s just protons. They were all formed in the Big Bang. So we actually carry about 10 percent of our body weight in us that is Big Bang material. The protons were all recycled numerous times throughout the stars, but the actual protons were made in the hot Big Bang when all the subatomic particles actually came together and formed protons and neutrons. And so that we are not just children of the stars. Actually we are also children of the Big Bang. And I think it’s really nice once in a while to reflect on that and really realize how much we are actually connected to the cosmos.