In order to understand how we study the universe, we need to talk a little bit about light. Light is a form of energy. Its wavelength tells us its energy and color. Spectroscopy allows us to analyze those colors and determine an object’s temperature, density, spin, motion, and chemical composition.
Forget the big bang. The real moment of creation was the Cosmic Dawn - the moment of first light. This is the scientific version of the story of Genesis. The big bang gets all the credit for creating our universe. But in fact, the universe it gave was dark and boring. There were no stars, no galaxies, just a vast, black fog of gas - the cosmic dark ages. But, after a hundred million years of nothing, came a dramatic moment of transformation - the Cosmic Dawn. It's the moment the first stars were born, the moment that lit up the Universe, and made the first structure and the first ingredients of life. This was the real moment of creation. Astronomers are now trying to witness the cosmic dawn. For the first time they have the tools to explore the very first stars of the universe and to tell the scientific story of our creation.
In this talk-show with the popular astrophysicist Neil deGrasse Tyson, Bill explores a variety of topics, including the nature of an expanding, accelerating universe (and how it might end), the difference between “dark energy” and “dark matter,” the concept of God in cosmology and why science matters.
Finding alien life on a distant planet would be amazing news - or would it? If we are not the only intelligent life in the universe, this probably means our days are numbered and doom is certain.