Read the Module Learning Objectives. Read the assigned text chapter including review questions etc at the end of the chapter. Then open and play the Power Point lecture. Next, have this downloaded module question document open with the Power Point lecture window open. The questions approximately follow the order of the lecture topics. Play the lecture again. When you reach the material covering a given question, pause the lecture, then open and use any interactive animation link preceeding that question.Some are very specific to the question. Others provide background to the questions. After doing these things, see if you can answer the question. Type or write notes directly into your downloaded or printed document. You should then be ready to take the Module Assessment quiz.
Module 12 Questions
Click to see processes near the center of our Milky Way Galaxy
1 A black hole of about ________ solar masses has been identified in the center of our galaxy. Its mass was estimated using the orbit ________ of a star orbiting around it.
A 30; size and period.
B 3 million; size and period.
C 30; orbit size.
D 3 million; size.
E 3 millon, period.
Click for active figure of accretion disk formation in star/black hole pair.
2 Jets are found in our Milky Way Galaxy emanating from
A terrestrial planets.
B jovian planets.
C planetary rings.
D accretion disks.
3 The most notable feature of Seyfert galaxies is
A the spiral arms.
B the supernova rate.
C the mass.
D the bright nucleus.
Click to see the giant E galaxy M87 in optical visual and x-ray wavelengths.

Click for interactive figure of twin radio galaxy beams and how they are affected by motion through intergalactic medium
Cleck to see active galaxies in radio, x-rays and visually.
.
4 The most notable feature of radio galaxies is
A jets of emission.
B lobes of radio emission far from the galaxy.
C accretion disk.
D all of the above.
5 Active galaxies are thought to have _______in their centers.
A massive black holes.
B the Local Group.
C a cluster of galaxies.
6 Astronomers who discovered quasars found that they show ________ of their spectral lines and are thus probably much ________ than nearby galaxies.
A large red shifts, farther away.
B large blue shifts, farther away.
C no wavelength difference, nearer.
D large red shifts, nearer.
E large blue shift, nearer.
7 Jet-shaped regions of radio and optical emission have been observed in
A quasars.
B radio galaxies.
C the 3° Kelvin radiation.
D both a and b.
8 One explanation of the dark sky Olber's Paradox is that light can reach us only from objects in space out to a distance in light years _______ the age of the universe in years.
A much less than.

B much greater than.
C equal to.
D less than or equal to.
E greater than or equal to.
9 How old is the universe since the Big Bang? Pick the best answer according to radioactive dating in the solar system, light travel times to most distant galaxies, time reversal of the
Big Bang expansion, and observations of the 3 degree K radiation.
A 1400 years.
B 14,000 years.
C 14,000,000 years.
D 14,000,000,000 years.
10 From the distances (D) of galaxies and their speeds (V) away from our galaxy, the age of the universe is approximately
A DV.
B D/V.
C V/D.
D 1/(DV).
11 By means of optical and radio telescopes astronomers can see light emitted from distant objects as they
A are right now.
B will be in the distant future.
C were in the distant past.
D All of the above.
E None of the above.
Click to see shift of peak of cosmic background radiation emission with time due to cosmic expansion is shown with schematic galaxies. You can pause then advance with buttons.
12. The 3° Kelvin radiation is thought to have originated in
A nearby galaxies today.

B gravitational repulsion.
C white dwarfs.
D the Big Bang long ago.
E the liquid cores of asteroids.
13. The observed 3° Kelvin radiation
A has a continuous thermal spectrum.
B has almost the same intensity over the whole sky.
C has its peak in the microwave spectral region.
D originated from a gas at a temperature of about 3000 K.
E All of the above are true.
14. In Big Bang cosmology, the critical density is ______
A the value needed for nuclear fusion of H nuclei.
B the value needed for nuclear fusion of He nuclei.
C just the value so gravity will not overcome the expansion.
D None of the above.
These interactive figures show the formation of elements in the universe. These should help with the next few questions.
Click through a first three minutes of the universe. Particles and reactions are shown and described until formation of light elements (primarily H and He).
Click to see an interactive animation of element formation in high mass versus low mass stars.
Click to view states of stellar evolution for low medium and high mass stars.
15 Astronomers believe that the hydrogen atoms in your body were created
A in the planets.
B inside exploding stars.
C in the sun.
D in the big bang.
E in neutron stars.
16 Astronomers believe that the Helium nuclei in the Sun were created

A in the planets.
B inside exploding stars.
C in the sun.
D in the big bang.
E in neutron stars.
17 Astronomers believe that the iron atoms in your body were created
A in the planets.
B inside exploding stars.
C in the sun.
D in the big bang.
E in neutron stars.
Click to see animations and description of ordinary matter, dark matter and dark energy as revealed with x-ray telescopes.
18 Astronomers calculate that there ________ mysterious dark matter as ordinary matter
A 5 times as much.
B 2 times as much.
C an equal amount of.
D 1/5 as much.
E 1/10 as much.
Click to learn about general relativity, dark energy and black holes.
Click for part II of above video.
19 The present-day recession of the galaxies away from one another ________ dark energy.
A is being accelerated (or speeded up) due to.
B is being decelerated (or slowed) due to.
C is not being affected.
20 Evidence for a very early "super rapid" inflation of the universe is based on ________ .

A 3 degree K features.
B Type I supernova estimates of galaxy distances.
C both of the above.
21 Planets around stars formed very early in the history of the universe
A will form from materials rich in Hydrogen and Helium.
B will form from materials deficient in elements necessary for life.
C Both of the answers are true.