How old is the Earth? In this lecture I review the ideas of cyclic and
linear time, and how this determines whether or not the question of the
age of the Earth is meaningful. I then review various ways people have
tried to estimate the age of the Earth, starting with historical ages
that equate human history with the physical history of Earth. We then
lo ... Show More
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
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