Star death

We study star death . Stellar evolution is in CM Chapter 20. There is a general discussion in Sec. 20.1. The stages in the life of a solar mass star are discussed in CM Sec 20.2. The death of a solar mass star is in CM Sec. 20.3. The evolution of more massive stars is in CM Sec. 20.4. We will not cover the material on evolution of stars in binary systems in CM Sec. 20.6.

The end stages of stellar evolution are discussed in CM Sec. 20.3 (white dwarfs); 22.1 and 22.2 (neutron stars); and 22.5 and 22.8 (black holes).

I hope that we have time to go over some of the main things that we have learned.

First, a main goal of the class has been to improve everyone's critical thinking skills. The "critical" part is demanding that ideas (theories) be supported by evidence and recognizing what evidence supports a theory or falsifies it. The "thinking" part is using available information plus logic to reach a conclusion, often with the help of a calculation. This is not so easy, but over the course of a four year university education, it is possible to get a lot better at it.

We have learned a lot about stars. Looking at the night sky, everything seems unchanging and peaceful. But it is not so. The time scale for changes is mostly longer than a human lifetime, but every star has a history. Furthermore, sometimes big things happen in just one second.

Not everything is known about astronomy. You will discover some real mysteries if you take ASTR 123. Two big mysteries are
  1. Most of the matter in the universe is "dark matter" that creates a gravitational force but is otherwise invisible. We don't know what the dark matter is.
  2. There also seems to be "dark energy" throughout the universe. The dark energy is causing the expansion of the universe to accelerate. We don't understand the nature of the dark energy.

ASTR 122 course home page

Updated 19 November 2007

Davison E. Soper, Institute of Theoretical Science, University of Oregon, Eugene OR 97403 USA