Textbook Notes (368,460)
Canada (161,892)
Astronomy (194)

Chapter 21 Summary Cosmic Perspective

1 Page
Unlock Document

Astronomy 1021
Chris Racknor

CHAPTER TWENTY ONE Galaxy Evolution We can study galaxy evolution by looking back through time and at great distances we see galaxies as they were when the universe was young and nearby we see mature galaxies as they exist today these observations along with theoretical modeling are helping us understand the lives of galaxies Galaxies probably all began as protogalactic clouds but they do not always evolve peacefully some galaxies suffer gargantuan collisions with their neighbours often with dramatic results The tremendous energy outputs of quasars and other active galactic nuclei including those of radio galaxies are probably powered by gas accreting onto supermassive black holes the centres of many present day galaxies must still contain the supermassive black holes that once enabled them to shine as quasars How We Observe the Life Histories of Galaxies Todays telescopes enable us to observe galaxies of many different ages because they are powerful enoygh to detect light from objects with lookback times almost as great as the age of the universe we therefore assemble family albums of ga
More Less

Related notes for Astronomy 1021

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.