Lecture 5: The Chemical Revolution and the Na...

The geological revolution revealed that the Earth is of great antiquity and yet has a history we can read in the land. We will discuss ideas of cyclic and linear time, historical versus physical age estimates, the discovery of geological time, and radiometric dating methods that ...  Show more

What is the nature of life? In this lecture I will review the revolution in biological thinking that has dramatically changed how we view life. I will review such persistent ancient ideas as spontaneous generation and why it took so long to disprove this notion, the impact of the ...  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