Lecture 09: Eclipses of the Sun and Moon

What time is it? Telling time is the oldest practical application of astronomy. Today's lecture is the first of a 2-part lecture on the astronomical origins of our methods of keeping time and making calendars. This lecture reviews the divisions of the year into the solstices, equ ...  Show more

How do we make calendars? This lecture explores the astronomical origins of our calendars. We start by discussing lunar and solar calendars and their hybrids in history and tradition (for example, the Islamic Lunar Calendar and the Hebrew Luni-Solar Calendar), and then describe t ...  Show more

Welcome to the Astronomy 161 Lecture Podcasts. This is a brief message from me explaining the podcasts, and welcoming new and old listeners. University. Lectures will begin on Wednesday, 2006 Sept 20, and run through Friday, 2006 December 1. New lectures will appear shortly befor ...  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

Before we can begin our exploration of astronomy, we 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. We will first re-introduce the basic metric system, explaining how t ...  Show more