Lecture 3: Imagining Other Worlds

Modern science was borne of an effort over many centuries to understand the motions of celestial bodies. The Copernican Revolution of the 16th and 17th centuries was the crucial moment in history when we finally understood the nature of celestial motions, and opened the door to t ...  Show more

What is the nature of matter, and how did we come to understand the chemical elements and atomic structure? This lecture is a brief and selective overview of the history of our understanding of the nature of matter and chemistry. We will also introduce spectroscopy and radioactiv ...  Show more

How can we search for extraterrestrial intelligence, and what are we looking for? This second part of a 2-part lecture picks up where we left off yesterday by examining SETI, the Search for ExtraTerrestrial Intelligence, and reviews what we might look for and how. We will use thi ...  Show more

What is Astronomy? What is Science? What is the course all about? Brief introductory remarks after going over course mechanics on the first day of Astronomy 161 for Autumn Quarter 2007. Recorded 2007 Sep 19 in 1000 McPherson Lab on the Columbus campus of The Ohio State University ...  Show more

Are we alone in the Universe? This lecture explores the question of how we might go about finding life on planets around other stars. Rather than talking about speculative ideas, like the Drake Equation or SETI, I am instead taking the approach of posing it as a problem of what t ...  Show more

What are our units of measure in astronomy? To begin our exploration of astronomy, we first need to develop a common language for notating large numbers, and introduce the basic units of length, mass, and time that we will use throughout the quarter. This lecture is a quick revie ...  Show more