If we ever detect life elsewhere, how will we go visit? This lecture
considers the challenges of interstellar travel and colonization. The
problem is one of basic physics (the enormous energy requirements of
star flight) coupled with the vast, irreducible distances between the
stars. I will describe various starship concepts that use reasonable
extrapolat ... Show More
Nov 2009
Lecture 42: The Fermi Paradox
So, Where is Everybody? Interstellar colonization, in principle, is an exponential growth process that would fill the galaxy in a few million years even with a very modest star flight capability. This is a small fraction of the lifetime of the Milky Way Galaxy, so the Galaxy shou ... Show More
44m 58s
Mar 2006
Lecture 44: Life, the Universe, and Everything (Life Part II)
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
45m 56s
Sep 2007
Lecture 02: Astronomical Numbers
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
43m 58s
Sep 2007
Welcome to Astronomy 161 for Autumn Quarter 2007
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, 2007 Sept 19, and run through Friday, 2007 Nov 30. New lectures will appear shortly before 6p ... Show More
7m 35s