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ASTR 101 Deming Spring 2002 EXAM I
MULTIPLE CHOICE QUESTIONS (2 pts. each)
Choose the BEST answer using what you have learned in ASTR 101. Indicate your
choice on the scantron sheet.
1. The planet that did not seem to fit well into either the jovian group or the terrestrial
group was
A. Mercury
B. Venus
C. Uranus
D. Neptune
E. Pluto
2. The “Powers of Ten” video shown in class and the “Introductory Chapter” in the
textbook represent our galaxy as having _____________________ shape.
A. a spiral
B. an elliptical
C. a circular
D. a star-shaped
E. an unknown
3. In the future, an astronaut on the Moon looks at the Earth and observes that the
Earth’s phase is first quarter. What is the phase of the Moon as seen from Earth?
A. new
B. first quarter
C. gibbous
D. crescent
E. last quarter
4. If a lunar eclipse occurs and is visible from College Park,
A. it must be night and new moon.
B. it must be night and full moon.
C. it must be day and new moon.
D. it must be day and full moon.
E. the Moon must rise at midnight.
5. The Earth's Moon is said to be in synchronous rotation. What does this term mean?
A. The Moon does not rotate; it only revolves.
B. The Moon only rotates; it doesn't revolve.
C. The Moon rotates once per revolution,
D. The motion of the Moon is synchronized with the motions of the moons of
outer planets.
E. The times of moonrise and moonset are so accurate that you can synchronize
your watch by them.
6. In the diagram below, the star labeled ___________ is Polaris, the North Star.
DIAGRAM WILL BE PROVIDED IN DISCUSSION SECTION
7. Kepler's third law states that the relationship between orbital period and semimajor
axis of the orbit of a planet is P2 = a3. To use this equation as written P must be
expressed in _____ and a must be expressed in _____.
A. perihelion; aphelion
B. years; kilometers
C. days; kilometers
D. years; astronomical units
E. days; astronomical units
8. Which of the following statements is NOT true of circumpolar stars?
A. They neither rise nor set.
B. They are always near the zenith.
C. Over 24 hours they circle around the NCP (or SCP).
D. They are always above the horizon.
E. As your latitude increases, there are more circumpolar stars.
9. How were the five naked eye planets noticed and recognized by ancient
astronomers?
A. These planets are the five brightest objects in the night sky.
B. Planets are observed to "twinkle."
C. Planets were observed to move with respect to the stars.
D. The epicycle of each planet is easily visible.
E. These planets always were observed to lie on the celestial equator.
10. The 5,200 year old tomb at Newgrange in Ireland shows an alignment with
A. the sun on the winter solstice.
B. the zenith passage of Polaris.
C. the moon on the vernal equinox.
D. the sun on the vernal equinox.
E. the North Celestial Pole.
11. What is meant by differentiation of a planet?
A. This term comes from calculus and was used by Newton to derive Kepler's
laws.
B. This term is used to describe the list of differences between the planets.
C. Each planet is unique.
D. This process leads directly to the formation of satellites.
E. During formation, the densest materials sank toward the core of each planet.
12. The declination of a star refers to its position from the
A. zenith.
B. ecliptic.
C. celestial equator.
D. vernal equinox.
E. autumnal equinox.
13. Planets near the Sun are composed of mainly rock and iron. How does solar system
formation theory account for this?
A. The Sun's magnetic field attracted all of the iron in the nebula toward the inner
solar system.
B. The forming sun's heat prevented other substances such as ices to condense
near it.
C. The planets that today are far from the Sun were captured.
D. The planets that today are near the Sun were captured.
E. All of the planets were captured, so the densest ones are closest to the Sun
due to gravity.
14. The numerous craters that we see on the solid surfaces of Mercury and the Moon
are evidence that
A. these bodies were so hot after they formed that volcanoes were widespread.
B. the Sun was so hot that it melted these bodies and made them boil forming
craters.
C. these bodies were originally a mix of water and rock, and as the water boiled
hollow pockets were created in the rock.
D. they were bombarded early during their history by debris leftover from
formation.
E. plate tectonics occurred on both of these worlds.
15. The Giant Impact Theory described in class accounts for the
A. formation of the Pacific Ocean.
B. extinction of the dinosaurs.
C. formation of the Sun and planets.
D. formation of the Earth’s Moon.
E. beginning of the Universe.
16. We know a lot about the Earth’s interior primarily from
A. the study of seismic waves.
B. deep mines dug to explore the mantle and core.
C. studying faults (cracks) in the Earth’s crust.
D. sea floor drilling.
E. the book “A Journey to the Center of the Earth” by Jules Verne.
17. Suppose that you are sitting in a boat floating in the middle of an ocean. You just
catch sight of Polaris near the horizon. You know that your location is
A. near the North Pole.
B. near the South Pole.
C. near the equator.
D. near latitude 39 degrees north.
E. near latitude 39 degrees south.
18. The Voyager I space probe has reached the speed necessary to escape from the
Sun's gravity. It currently is 10 billion kilometers from Earth. Its engine suddenly
malfunctions and is no longer operational. What would happen next to Voyager I?
A. It will stop immediately.
B. It will slow down and quickly come to a stop.
C. It will slow down and be pulled back toward the Sun.
D. It will continue to move at the same speed in a straight line.
E. It will continue to move but be drawn into a large elliptical orbit around the
Sun.
19. The Apollo astronauts on the Moon (as shown in the video in class) wore spacesuits
because they needed
A. protection from the harsh conditions found on the Moon.
B. oxygen to breathe since the Moon has no atmosphere.
C. a heavy spacesuit to prevent them from floating since the Moon has no
gravity.
D. all of the above answers are correct
E. only answers A and B are correct
20. Which of the following could NEVER be seen from College Park at midnight?
A. Mercury
B. Mars
C. Jupiter
D. a waxing gibbous moon
E. a waning gibbous moon
21. According to Kepler's model of the solar system, retrograde motion is caused by
A. epicycles.
B. the Earth's rotation.
C. the difference in orbital speed of Earth and other planets.
D. the changing speed of the Sun.
E. the daily turning of the celestial sphere.
22. Astronomers are convinced that liquid water was present on Mars in the past
because
A. huge subsurface deposits of ice have been seen with X ray telescopes.
B. during each Martian summer large lakes form as the polar ice cap melts.
C. there is a huge amount of water vapor in the Martian clouds.
D. spacecraft have photographed features on the surface showing water erosion.
E. we have observed dark vegetation growing along the canals.
23. Bill travels to another planet with twice the Earth's radius. You know that Newton
expressed gravity as F = G m M / r2 . Bill weighs 160 lbs on Earth, what would Bill
weigh on this planet?
A. 40 lbs.
B. 80 lbs.
C. 160 lbs.
D. 320 lbs.
E. 640 lbs.
DIAGRAM WILL BE PROVIDED IN DISCUSSION
24. Which telescopic observation did Galileo make that was the most damaging to the
geocentric theory?
A. the phases of Venus
B. the lunar mountains
C. Jupiter’s great spot
D. Saturn’s ring
E. sunspots
25. The volcanoes on Mars are much larger than the volcanoes on Earth because Mars
A. is older than Earth.
B. has no atmosphere.
C. has a strong magnetic field.
D. has two moons instead of one.
E. lacks plate motion.
SHORT ANSWER QUESTIONS (50 PTS.)
Answer these questions as completely as you can using what you have learned in
ASTR 101. Put your answers directly on these pages. Be sure to indicate name and
section on next 4 pages.
26. a) Hipparchus discovered precession. What is precession? Give two effects that
astronomers notice as a result of precession. (4 pts.)
b) A video was shown during lecture that showed the “Sun Dagger.” Describe the
astronomical significance of this site. (4 pts.)
c) Give 2 observations that support the theory of continental drift. (2 pts.)
27. a) Make a sketch showing the positions and orientations of the Sun and Earth
during December. Be sure to label your sketch for clarity. (4 pts.)
b) Compare December weather in College Park, Maryland (latitude = 39 o N) and in
Valdivia, Chile (latitude = 39o S). Explain any differences. (4 pts.)
c) How did Mrs. Deming demonstrate that the weight of a body doesn’t affect its
gravitational acceleration (falling rate)? (2 pts.)
EXTRA CREDIT (2 pts. maximum)
Recently an occultation occurred (unfortunately it was cloudy so we couldn’t observe it).
Describe what happened during this event.
28. a) The geocentric theory of Aristotle and Ptolemy was believed for centuries. How
was the geocentric theory so convincingly supported by Greek scientists? (4 pts.)
b) Describe Tycho Brahe’s observations. How did they contribute to eventually
understanding the true arrangement of the Solar System? (3 pts.)
c) Kepler revised the Copernican heliocentric theory during the early 1600s. What is the
major difference between the theories of Copernicus and Kepler? (2 pts.)
d) The most abundant gas in Earth’s atmosphere is ______________________. (1 pt.)
29. a) Make a labeled sketch showing how the greenhouse effect is produced.
Explains what happens at crucial points on your sketch. (5 pts.)
b) List the dominant greenhouse gas for Earth and for Venus. Compare the surface
atmospheric pressure on these two planets. (4 pts.)
c) Describe the technique used by astronomers to map the surface of Venus. (3 pts.)
30. Use the following diagram to answer the following questions:
DIAGRAM WILL BE PROVIDED IN DISCUSSION SECTION
a) The Moon is at the position labeled B. Sketch the Moon as it would appear to you on
Earth. (1)
b) The phase of the Moon in part a is ____________________________. (2)
c) Estimate the time the moon would rise in part a? (1)
d) What position (in the sketch above) would the moon have to be at to observe
earthshine easily? ___________ (1)
e) Why does the Earth have relatively few impact craters compared to the Moon? (3
pts.)
EXTRA CREDIT: Does Mars have a greenhouse effect? Explain your answer. (2)