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

2MASS Survey Infrared Map of the Milky Way
[Credit: Two Micron All Sky Survey Project]

Unit 4: "Island Universes"
The Milky Way & External Galaxies

Having completed our overview of stellar structure and evolution, we are now ready to explore the Milky Way Galaxy and continue on to other "external" Galaxies. Galaxies are vast systems of billions of stars that populate the Universe.

We will begin our discussion with an historical overview of our discovery of the nature of the Milky Way, and the discovery that the other "spiral nebulae" were in fact other "milky ways"; vast galaxies of stars like our own. This requires that we address and then attempt to solve (with varying degrees of success) the problem of measuring distances beyond the reach of trigonometric parallaxes.

We will then move on to a discussion of the modern view of the structure of galaxies, beginning with an examination of our Galaxy and its nearby cousin, the Andromeda Galaxy. From there we will treat galaxies in general, and end with a discussion of groups and clusters of galaxies, look at what happens when pairs of galaxies collide, and examine the active galaxies & quasars which will prove to be beacons lighting our way across much of the observable Universe.


The Cosmic Distance Problem (Feb 6)

The Milky Way (Feb 7)

"The Realm of the Nebulae" (Feb 8)

A Tale of Two Galaxies: The Milky Way & Andromeda (Feb 9)

Spiral Galaxies (Feb 10)

Spirals & Ellipticals & Irregulars (Feb 13)

Groups & Clusters of Galaxies (Feb 14)

When Galaxies Collide: Interacting Galaxies (Feb 15)

Active Galaxies & Quasars (Feb 16)

Quiz 3: Friday, February 17 (in class)
Lecture Podcasts Lecture Audio Podcasts

Associated Readings in Universe are listed at the top of each of the lectures.

[ Return to Astronomy 162 Main Page | Go back to Unit 3 | Go forward to Unit 5 ]
Updated: 2006 February 19
Copyright Richard W. Pogge, All Rights Reserved.