NAME _____________________________ LAB Section # __________________
Astronomy 1001, Midterm #1 - Feb. 28th Dr. Robert D. Gehrz - Spring 2005
Read Instructions Carefully:
The essay questions of this exam may be graded by more than one person, so it is imperative that your NAME BE LEGIBLY WRITTEN ON EACH PAGE OF THE ESSAY PORTION!
1. MARK THE ANSWERS YOU CHOOSE ON THIS TEST AS IT IS YOUR ONLY
OPPORTUNITY TO CHECK WHICH ANSWERS YOU GOT RIGHT OR
WRONG. This will not be done for you at a later time in the departmental office.
Exams will be returned to the alphabetical boxes in the North wall of the Physics
building approximately 3-4 days after the exam.
2. Print your NAME, ID # and SECTION # on your answer sheet where appropriate. Your
SECTION # should read 02. All three items are necessary for the proper scoring and
computer transfer of your scores.
3. Use a pencil, make your marks dark and neat, and erase thoroughly.
4. There is only one answer to each question. Choose the best answer.
5. You may use this test for scratch paper.
6. One page (two sides) of notes is allowed for the exam.
I. Multiple Choice (3.2 pts. each)
1. How are lunar craters formed?
a. Pieces of the Moon fall off, leaving holes in its surface
b. Solid bodies such as asteroids strike the Moon's surface
c. Craters are extinct volcanoes
d. Both a and c
2. Astronomers wish to build larger and larger telescopes because larger telescopes:
a. allow fainter objects to be seen.
b. allow smaller angles (more detail) to be resolved.
c. give higher magnification of the image.
d. both (A) and (B).
3. The earth's core is much more dense than the crust or mantle. This fact can be used to infer what about the earth's history?
a. The metals accreted first and then the silicates
b. The earth accreted by collisions of asteroid-like bodies and comet nuclei
c. The entire planet was molten at one time
d. The sun heated the earth more in the past than now
4. What causes a solar eclipse?
a. The moon's shadow falls on a small portion of the earth
b. The earth covers the sun, as viewed from the moon
c. The sun's shadow covers the earth, as seen from moon
d. The earth's shadow falls on the full moon
5. A planet's average density is equal to its __________ divided by its ___________.
a. mass, surface area b. volume, mass c. mass, volume d. mass, radius
6. List the regions of the electromagnetic spectrum from short to long wavelengths.
a. Gamma rays, X-rays, Ultraviolet, Visible light, Infrared, Radio waves
b. Radio waves, Infrared, Visible light, Ultraviolet, X-rays, Gamma rays
c. Gamma rays, X-rays, Infrared, Visible light, Ultraviolet, Radio waves
d. Radio waves, Ultraviolet, Visible light, Infrared, X-rays, Gamma rays
7. Relative to the horizon, as seen from the northern hemisphere, the stars daily:
a. rise in the east and set in the west
b. rise in the west and set in the east
c. move mostly in a northward direction
d. move mostly in a southward direction
8. Why is the Moon's surface cratered but the Earth's is not?
a. The Moon was bombarded with large rocks, but the Earth was not
b. Meteors bounce off the Earth's atmosphere
c. The Earth's surface once had craters like the Moon's, but they were obliterated by erosion and plate tectonics
d. Human activity on Earth has wiped out all traces of craters
9. Which of the following properties of the Jovian (Giant) planets distinguish them from the terrestrial (earth-like) planets ?
a. Low average density b. Ring systems c. Fast rotation d. all of the above
10. What is the celestial equator?
a. A band of constellations through which the planets and Sun appear to move
b. The line that the sun traces across the celestial sphere
c. The extension of the Earth's equator on the celestial sphere
d. The cycle of lunar phases
11. For the terrestrial planets to form, the planetesimals had to:
a. accrete to make the proto-planets
b. move in from the asteroid belt
c. collide and fragment each other into smaller pieces
d. melt from radioactive decay and then reform
12. Why does Mars go into retrograde motion?
a. The rotation of the Earth
b. The Earth overtakes Mars as it orbits the sun
c. Mars moves around the Earth
d. The Earth move around Mars
13. Which of the following is a contribution that Copernicus made to astronomy?
a. He determined the size of the Earth
b. He discovered epicycle
c. He developed the first successful heliocentric model of the solar system
d. He was the first person to point a telescope at the sky
14. What is the ecliptic?
a. A band of constellations through which the planets and Sun appear to move
b. The line that the sun traces across the celestial sphere
c. The extension of the Earth's equator on the celestial sphere
d. The cycle of lunar phases
15. The gravitational force exerted by the Sun on the Earth is ____ the gravitational force exerted
by the Earth on the Sun.
a. greater than b. less than c. equal to d. unrelated to
16. What is the phase of the moon for a lunar eclipse?
a. New b. First quarter. c. Full Moon. d. Third quarter
17. Which concept below was NOT part of Kepler's laws?
a. The planet orbits are ellipses
b. The closer a planet is to the Sun, the faster it moves
c. Retrograde motion required use of epicycle
d. The sun lies at one focus of all elliptical planetary orbits
18. The earth’s crust is broken into large plates that are in motion on its surface by the
a. moon’s gravitational pull
b. rotation of the Earth
c. rolling convective motions of the Earth’s mantle
d. precession of the earth’s axis of rotation
19. What is the celestial sphere?
a. The Sun
b. The Moon
c. The Earth
d. An imaginary sphere surrounding the Earth, where all the stars lie
20. The large number of craters on the lunar highlands compared to those on the maria is evidence that the
a. surface of the maria is liquid and craters quickly disappear there
b. material composing the highlands is very soft and easily cratered
c. maria are much younger than the highlands
d. maria are much older than the highlands
21. Which of the following (A-D) are examples of an object accelerating?
A. an object at rest
B. an object in motion in a straight line at a constant speed
C. an object in motion in a straight line with increasing speed
D. an object moving in a circle at constant speed
a. A only
b. All but A
c. C only
d. Both C and D
22. One reason we infer that the earth's core is metallic is that:
a. the average density is greater than the surface density
b. the surface density is greater than the average density
c. most of the continents are made of metals
d. earthquakes can only occur if the core is metallic
23. How many times does the Moon rotate about its axis during one orbit around the Earth?
a. 0 b. 1 c. 14 d. 28
24. During a total lunar eclipse, the moon is a faint coppery red color because:
a. The moon glows due to its surface heat
b. Red light is refracted into the Earth’s shadow by the atmosphere of the Earth
c. The earth does not completely cover the sun as viewed from the moon
d. Both a and b
e All of the above
25. What type of spectrum is emitted by a heated solid object (such as the filament of an
incandescent bulb)?
a. Continuous b. Emission line c. Absorption line d. None of the above
NAME _____________________________ LAB Section # __________________
Astronomy 1001, Midterm #1 - Feb. 28th Dr. Robert D. Gehrz - Spring 2005
II. Short Essays (16 pts each)
1. Explain in your own words what physical conditions and processes make the surface of the planet Venus so much hotter than expected for its distance from the sun.
2. State in your own words and explain the meaning of Newton’s three laws of force and his law of gravity.
3. State in your own words and explain the meaning of Kepler’s three laws of planetary motion.
NAME _____________________________ LAB Section # __________________
Astronomy 1001, Midterm #1 - Feb. 28th Dr. Robert D. Gehrz - Spring 2005
4. Show with the aid of labeled diagrams how refracting and reflecting telescopes bring rays of light to a focus.
5. Four theories have been proposed to explain the presence of our moon: capture, coeval (simultaneous formation), fission, and giant impact. Briefly discuss the pros and cons of each.