AY 101-002                                                        Spring 2008
                                   QUIZ #9

Answer each of the following on a computer-gradeable answer sheet. Be
sure to fill in your name and student number (and blacken their circles as 
well). Write your seat number on a corner of the answer sheet.

1. Edwin Hubble demonstrated that other galaxies beyond the Milky Way exist,
   a) by measuring their speeds of rotation from repeated photographs.
   b) by measuring their distances using parallax.
   c) by using red-sensitive photographs to penetrate obscuring dust clouds.
   D) BY FINDING VARIABLE STARS OF A WELL-UNDERSTOOD TYPE IN OTHER GALAXIES.

2. The Hubble classification includes these galaxy types:
   A) ELLIPTICAL, BARRED OR ORDINARY SPIRALS, OR IRREGULAR.
   b) quasars, Seyfert galaxies, or radio galaxies.
   c) clustered, isolated, or interacting.
   d) giant, normal, or dwarf systems.
   
3. If we could see only the "population I" part of our Galaxy, it would
   a) have a round shape.
   b) appear much larger than the actually visible Galaxy.
   C) FORM A THIN, FLATTENED DISK SHAPE.
   d) include both the central bulge and the spiral pattern.

4. As seen from the Sun, stars of Population II
   a) have higher amounts of iron and other metallic elements.
   B) MOVE FASTER THROUGH THE GALAXY THAN POPULATION I.
   c) are more tightly concentrated into spiral arms.
   d) formed later.

5. Herschel's early attempt to probe the size and shape of the Milky Way
   fell far short, because
   a) he had only access to the northern celestial hemisphere.
   b) his telescope could not see faint enough stars.
   c) the kinds of stars in our Galaxy change from place to place.
   D) IT WAS NOT YET KNOWN THAT THERE IS DUST IN SPACE ABSORBING LIGHT.

6. Based on its stellar content and form, the Milky Way is found to be
   a) an irregular galaxy.                C) A SPIRAL GALAXY.
   b) an elliptical galaxy.               d) an emission nebula.

7. The properties of the different stellar populations suggest that
   A) THE MILKY WAY CONTRACTED FROM A HUGE CLOUD OF GAS WHILE FORMING STARS.
   b) the Milky Way acquired most of its gas late in cosmic history.
   c) the Milky Way started as an elliptical galaxy.
   d) Population II stars originated in the galactic center.

8. Evidence that galaxies include vast amounts of dark matter does NOT include
   a) gravitational lensing.
   b) the pattern of orbital velocity with location in spiral galaxies.
   C) THE ABSORPTION OF LIGHT BY PARTICLES IN THE GALAXIES.
   d) Doppler shifts of galaxies within clusters.

9. The strongest evidence for the small size of quasars comes from
   A) THE TIME IT TAKES THEIR BRIGHTNESS TO CHANGE.
   b) how small they appear in telescopes.
   c) comparing their sizes to their surrounding galaxies.
   d) the strength of their radio emission.

10. Mergers between galaxies can
   a) transform the galaxies' structure.
   b) trigger massive bursts of star formation.
   c) sweep the galaxies' gas away into the surrounding space.
   D) DO ALL THE ABOVE.