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Galaxy NGC4414 from HST Astronomy 162:
Introduction to Stars, Galaxies, & the Universe
Prof. Richard Pogge, MTWThF 9:30

Course Introduction:
Light, Matter, & Gravity

Nearly everything we know about the Universe beyond the Earth has been learned from a distance. We cannot yet directly measure a star other than the Sun, or scoop up a bit of its material to study in a laboratory. We have only the light that comes to us from across the vast, effectively unbridgable reaches of space. Because light, Electromagnetic Radiation, is produced by and interacts with ordinary matter, we can decode the message of the light, and learn a great deal about extremely distant objects. It was only when astronomers began to understand the nature of light, how it is produced and how it interacts with matter, that "Classical Astronomy", which was primarily concerned with the positions and motions of the stars, gave way to the modern study of "Astrophysics", which is our study of how stars, galaxies, and the universe work.

In this introductory section, we will start with an overview of the course, and then re-introduce some ideas from Astronomy 161 on the nature of Light, Matter, and Gravitation. These are the basic physical tools we need to "decode" the message of light from space to learn about the physics of objects too distant to touch directly.


Course Introduction (Jan 3)

Light the Messenger (Jan 4)

Matter & Light (Jan 5)

Matter & Gravity (Jan 6)

Associated Readings in Universe:

Chapter 5, and Chapter 4 section 4-7

The links above reproduce the electronic overheads shown in class for each of the lectures. In some cases they have additional text and links covering supplemental material or graphics. Online lecture notes are made available starting the week in which the lectures occur, but some notes may not be accessible until later in the week if I am having problems translating them into a web-accessible form.

Please feel free to print out copies of these lecture outlines in advance of class, so you can follow along with the lecture. Many students find this helps them listen without the pressure of taking down detailed notes of their own, but while still making additional notes in the margins to highlight particularly emphasized points.

Also, see A Note about Graphics if you are curious as to why some of the pictures shown in the lectures are not reproduced with these notes.

Students wishing to explore some of these topics beyond the lecture and textbook using the Internet might want to look at the relevant Selected Astronomical Internet Links for this unit.

[ Return to the Astronomy 162 Main Page | Go forward to Unit 1 ]
Updated: 2006 January 4
Copyright Richard W. Pogge, All Rights Reserved.