You have to decide which chapter each question comes from and whether that chapter will be on your exam. Be very careful.

Previous Page of Astronomy Exam Questions

1. (10 points)

a) What is the typical distance between stars in our neighborhood of the galaxy?

b) About how many stars are in our galaxy?

c) About how far away is the Andromeda Galaxy?

d) About how long does it take light to travel between the Earth and the Moon?

e) About how long does it take light to travel between the Earth and the Sun?

2. (8 points)

a) Make a sketch showing the Earth, the Sun and the path the Moon takes around the Earth. On the sketch show and label the location of the Moon when it is a full moon. Indicate the direction that the Moon goes around the Earth and the direction that the Earth rotates.

b) On your sketch show where you would be standing on Earth if you were looking at the Moon highest in the sky. Label this “me”.

c) What is the time of day or night when the full Moon is highest in the sky? Briefly explain how you arrive at your answer.

3. (7 points)

In a paragraph or two explain how satellites work? Why don’t they fly off into space, and more importantly why don’t they come crashing down and hit the Earth?

4. (5 points)

a) In approximately what year did Kepler publish his three laws concerning the motion of the planets?

b) Kepler’s first law describes the shape of the orbits of the planets. What is Kepler’s first law? (It has more than one part.)

5. (2 points) Pick the statement which is the most accurate:

a) The Sun goes around the Earth once every day?

b) The Earth goes around the Sun once every day?

c) The Sun goes around the Earth once every year?

d) The Earth goes around the Sun once every year?

6. (2 points) Several decades ago astronauts landed on the Moon. They were able to walk on the Moon without drifting off into space because a) the gravity of the Earth extends all the way to the Moon and that held them to the Moon, b) they wore strong magnets on their boots, c) the Moon has its own gravity which pulled them toward the surface of the Moon, d) they wore special heavy boots, or e) they had ropes with hooks to hold them to the surface of the Moon. Pick one

7. (2 points) Place the following in the order in which they made their contributions to astronomy:

a) Keith Richards, b) Copernicus, c) Ptolemy, d) Kepler, e) Newton.

8. (2 points) Which has a longer wavelength, red light or green light?

9. (2 points) Which has a longer wavelength, x-rays or ultraviolet light?

10. (10 points)

a) Make a sketch showing the spectrum of a black body. Be sure to label both axes on your graph. We will assume that the peak of your black body spectrum is in the middle of the visible light range.

b) Place a second curve on your spectrum for a black body hotter than the first black body you just put on the sketch, and label this curve hot.

c) Assuming the first black body you sketched would appear white, what would the appearance of the second black body be? Would it appear white also, pink-white or blue-white? Briefly describe how you arrive at your answer.

11. (2 points) The spectrum of the Sun is a) just a black body spectrum, b) a black body spectrum with some absorption lines, c) a black body spectrum with some emission lines, or d) a combination of emission lines and absorption lines. Pick one.

12. (2 points) During the production of an absorption-line spectrum an electron a) stays in one energy level, b) moves to a higher energy level, c) moves to a lower energy level, or d) moves to a higher energy level and then moves to a lower energy level. Pick one.

13. (2 points) Which will be a better telescope for astronomical purposes a) a refracting telescope with a 5 inch lens and a magnification of 200, b) a reflecting telescope with 12 inch mirror and a magnification of 100. Pick one.

14. (2 points) Which of the following does not easily pass through the Earth’s atmosphere: a) visible light, b) radio waves, c) x-rays, or d) microwaves. Pick one only.

15. (2 points) The Hubble Space Telescope is one of the best astronomical telescopes in the world because a) it is the largest telescope in the world, b) it is above the Earth’s atmosphere, c) it gathers more light than any other telescope in the world, or d) it has the most expensive mirrors and lenses of any telescope ever made. Pick one.

16. (10 points)

a) What two elements make up most of the Sun?

b) What is the approximate temperature of the photosphere of the Sun?

c) What is the spectral type (O, B< A, F, G, K, or M) of the Sun?

d) About how old is the Sun?

e) What is the name of the outer atmosphere of the Sun, the top layer? It is very thin, whispy glowing gas, and is quite hot.

17. (10 points) Suppose the hydrogen fusion rate in the core of a main sequence star speeds up for some reason. List the steps following this speeding which eventually lead to the decrease of fusion in the core and thus lead to stability. The star is still a main sequence star at the end of the period of adjustment. Give all the steps, in a logical order. (You can make a list of phrases, they do no have to be complete sentences.)

18. (15 points)

a) Make a sketch of a Hertzsprung-Russell diagram. Be sure to label the axes. Show and label the main sequence, red giants, and white dwarfs.

b) Indicate which main sequence stars will eventually evolve into black holes and label them “B.H.”

c) Indicate which main sequence stars will eventually evolve into white dwarfs and label them “W.D.”

d) If a main sequence star does not evolve into either a black hole or a white dwarf, what does it evolve into at the very end of its life?

19. Once iron is produced in the cores of large Red Giants something different happens to the fusion process.

a) (5 points) What makes iron and nuclei with larger masses than iron different from smaller mass nuclei when it comes to fusion?

b) (10 points) In a paragraph or two describe what happens to the core of a star once iron stars fusing. Describe the events that eventually produce a supernova. (There are a number of events which lead to the supernova. Be sure to mention the formation of neutrons, rebounding, neutrinos, and what produces the very large amount of fusion which makes a supernova one of the largest explosion in the universe.)

20. (15 points)

a) In a sentence or two what is a black hole?

b) Is it possible to orbit a black hole? Explain.

c) What would happen to your body if you got too close to a black hole? (Try not to use the word “suck”. You would not necessarily get sucked into the black hole. Being sucked into the black hole is not the answer I am looking for.)

21. (5 points) In a few sentence where were the heavy metals that we find on Earth produced. What was the event which produced them and how did it happen that they became a part of the Earth.

22. (10 points)

a) Make a sketch showing the top view of the Milky Way Galaxy. Show and label the nucleus and a few spiral arms.

b) Make a sketch showing the edge view of the Milky Way Galaxy. Show and label a few globular clusters, and the nucleus.

c) On your edge view sketch you made for part b show and label the approximate location of the Sun.

23. (10 points)

a) What is a “standard candle”?

b) How is a standard candle used to determine distances to galaxies?

c) Give an example of two types of standard candles?

24. (2 points) The cosmic horizon is a) the farthest distance that one can observe things in the universe because of the finite speed of light, b) the minimum distance from a black hole that one can still escape from the gravitational pull of the black hole, c) the distance beyond which we see nothing because of the expansion of the universe, or d) the time of the Big Bang. Pick one.

25. (2 points) Olber’s paradox a) is the name applied to the puzzle as to why there are so many chunks of frozen material just outside our solar system, b) is explained by the fact that the universe is not infinitely old and by the fact that the universe is expanding, c) is explained by the fact that there is dark matter in the universe which absorbs light from very distant stars, or d) is explained by the fact that there was a time when the universe underwent rapid expansion. Pick one.

26. (2 points) If our universe is spherical then a) it is finite and has no edge, b) it is infinite in size and has no edge, c) the universe will expand forever, or d) it has four spatial dimensions. Pick one.

27. (2 points) At the time of the Big Bang the universe was a) dense and cold, b) cold and not dense, c) dense and hot, or d) hot and not dense. Pick one

28. (2 points) Cosmic background radiation is light which originated a) when galaxies formed just after the Big Bang, b) just as the universe became transparent, c) when the first stars formed in the universe, or d) at the very beginning of the Big Bang. Pick one.

29. (10 points)

a) Which planets are mostly made of gas? Name them in order of increasing distance from the Sun.

b) Which planets are mostly made of rocky material? Name them in order of increasing distance from the Sun.

c) Most (but not necessarily all) of the moons of Jupiter and Saturn are made of a) mostly frozen stuff or b) mostly rocky stuff. Pick one.

d) Which moon of Jupiter is made mostly of rocky stuff?

e) Which planets have moons which are large enough to be spherical?

30. (10 points) Here it is! In a paragraph or two with a fine figure to help you description, what is the greenhouse effect? (In your description be sure to mention the types of electromagnetic waves involved, and the names of the two greenhouses gasses that we have in the Earth’s atmosphere. Do not use the words “bounce” or “trapped” or any related words!)

31. (10 points) In a paragraph or two what are maria (on the Moon) and how were they formed? Feel free to include a sketch if you like.

33. (5 points)

a) What is the nucleus of a comet made of? Brief description?

b) Why does a comet become visible only when it gets close to the Sun?

34. (5 points) In the Drake equation we are asked to make an estimate of the typical lifetime of a technologically advanced civilization (one capable of communicating over stellar distances.) In your estimate how long do you think the typical technologically advanced civilization last? Explain how you arrived at your answer. If you pick a small number of years (say less than 100,000 years) why don’t you think it will last longer? If you pick a large number of years (over 100,000 year) what makes you think these civilizations will not destroy themselves with careless use of their knowledge.

This page prepared by C. Hartley, Director of the Ernest B. Wright Observatory at the Department of Physics at Hartwick College in the City of Oneonta, NY. More things from C. Hartley at his home.

All text, graphics and photgraphs copyright ©2003 by C. Hartley unless otherwise noted.