Her e at the university of Arizona we make the largest mirrors in the world. So astronomy is limited by light gathering power. When you want to look far in the universe or look for faint stars or exoplanets, you have to gather as much light as possible. So the push is on to build bigger and bigger telescopes and we're building the mirrors for those big telescopes right here. Here. [MUSIC] The mirror behind me is one of what will be 7 mirrors, all of this size, that will go together like flower petals with a central piece to make the biggest telescope in the world. Basically, a 24 meter optical telescope called the giant Magellan telescope that's destined for Chile. And we, University of Arizona and Stewart Observatory, we're 10% partners. This is a billion dollar project, this is big science in every sense of the word. My name is Chris Impey, I'm a University distinguished professor of astronomy at the University of Arizona and I've been here for almost 30 years doing research on super massive black holes and distant galaxies and teaching astronomy. This online course, Astronomy, Exploring Space and Time, is the culmination for me of teaching to a very wide audience to try and convey the excitement of astronomy and especially the research that's going on right now, which is all around us at Steward Observatory. So this course is an overview of astronomy. Nothing is left out. We're talking about everything from comets to cosmology and we're talking about how we know what we know. That's important. How can we prove or understand the universe 13.7 billion years ago in the big bang, how do we know what it's like inside a star? How do we know there are planets that might have water on them light years away? So the method of science shows us that we can use evidence, remote information, remote sensing, light and other electromagnetic radiation to learn these things. And then we talk about the tools and these are the amazing new tools of astronomy, these huge telescopes and also huge detectors. And so the progress of the class goes inside out, you know. It starts from our neighborhood and works out through the solar system to twins of our solar system, and perhaps, earth clones that we might be finding into the architecture of the Milky Way and all the exotic end states of stars, which are interesting to a lot of people. Black holes and neutron stars, places where relativity is dominant and where space and time are warped and distorted and then out into the universe of galaxies, and then talk about the whole thing. Cosmology, the study of the universe, as a single entity. [MUSIC] These tools are very sophisticated and very expensive. This giant Magellan telescope will, in the end, cost about a billion dollars, so this is big science. But astronomy really starts with curiosity. It starts with something that costs nothing. It's built into every human brain, the curiosity of where we come from, what is our position in the universe, and what's the nature of the universe? So I hope everyone enjoys this class and interacts with me and the material and gets a flavor of modern astronomy. [MUSIC]
