164 Module Introduction
“There are at least as many galaxies in our observable Universe as there are stars in our galaxy.”
Martin Rees
Lord Rees of Ludlow
Astronomer
(1942 -)
This module presents an overview of the islands of stars found throughout the Universe: the galaxies. Like many objects we have discovered, galaxies vary in characteristics such as size, shape, and age.
Objectives
Upon completion of this module, the student will be able to:Upon completion of this module, the student will be able to:
- Define what a galaxy is and the broad characteristics of galaxies, including galaxy types.
- Explain the history of observing galaxies.
- Recognize Hubble’s Law and its implications in astronomy.
- Differentiate among galaxy-related objects, including Quasars, Blazars, galactic grouping, WIMPs, gravitational lensing