Bell Question 11/09/11 1.Describe the life cycle of a star the size of our sun. (5 pts.)

Three types of Galaxies

A spiral galaxy has a nucleus of bright stars and flattened arms that spiral around the nucleus.

Elliptical galaxies have various shapes and are extremely bright in the center and do not have spiral arms.

An irregular galaxy has no particular shape, and is fairly rich in dust and gas.

Evidence for the Big Bang cosmic background radiation - uniformly detected from every direction in space; considered a remnant of the big bang.

What the Universe is Made of 4% Stars and planets 23% Dark Matter – doesn’t give off light but has gravity 73% Dark Energy - ??? May be a force that opposes gravity

1. What accounts for different stars being seen in the sky during different seasons of the year? A. Stellar motion around Polaris B. Earth’s rotation on its axis C. Earth’s revolution around the sun D. Position north or south of the equator

1. What accounts for different stars being seen in the sky during different seasons of the year? A. Stellar motion around Polaris B. Earth’s rotation on its axis C. Earth’s revolution around the sun D. Position north or south of the equator

2. How do stellar spectra provide evidence that stars are actually moving? F. Dark line spectra reveal a star’s composition. G. Long exposure photos show curved trails. H. Light separates into different wavelengths. I. Doppler shifts occur in the star’s spectrum. Chapter 30

2. How do stellar spectra provide evidence that stars are actually moving? F. Dark line spectra reveal a star’s composition. G. Long exposure photos show curved trails. H. Light separates into different wavelengths. I. Doppler shifts occur in the star’s spectrum. Chapter 30

3. What happens to main sequence stars when energy from fusion is no longer available? A. They expand and become supergiants. B. They collapse and become white dwarfs. C. They switch to fission reactions. D.They contract and turn into neutron stars. Chapter 30

3. What happens to sun-like main sequence stars when energy from fusion is no longer available? A. They expand and become supergiants. B. They collapse and become white dwarfs. C. They switch to fission reactions. D. They contract and turn into neutron stars. Chapter 30

4. Which type of star is most likely to be found on the main sequence? F. a white dwarf G. a red supergiant H. a yellow star I. a neutron star Chapter 30

4. Which type of star is most likely to be found on the main sequence? F. a white dwarf G. a red supergiant H. a yellow star I. a neutron star Chapter 30

5. Evidence for the big-bang theory is provided by A. cosmic background radiation B. apparent parallax shifts C. differences in stellar luminosity D. star patterns called constellations Chapter 30

5. Evidence for the big-bang theory is provided by A. cosmic background radiation B. apparent parallax shifts C. differences in stellar luminosity D. star patterns called constellations Chapter 30