SCI-103 Introductory Astronomy Exam #1 Spring 2013
This is a take home exam. You must turn the exam in at the very beginning of your class on Tuesday, Feb 12.
No late exams will be accepted unless authorized prior to the due date/time.
Name_____________________
Class Meeting Time_____________
Grade Summary (To be completed by the Instructor)
HW #1_____________ (out of 20 points)
HW #2_____________(out of 20 points)
HW #3_____________(out of 20 points)
Extra-Credit Work _________________
Exam #1 ___________ (54 points total)
Grade So Far _______
This is a pretty meaningless measure of your performance in the course as a whole given
that we were only 3 weeks into the course, but it does say something as to your success in
learning the new material.
Answer the following Multiple Choice Questions by circling the correct response.
1) Imagine that you are visiting Antarctica on a cruise to see penguins. You step outside at night and look at
the stars. Where would you look to see the South Celestial Pole?
A) North, near the horizon (0 altitude)
B) Near the zenith (90altitude)
C) North, near 43 altitude
D) Northwest, in the direction towards the U.S.A.
E) The SCP cannot be seen from this location.
2) During Spring Break you and your friends plan to travel south to Cancun, Mexico for a week of sun and fun.
You arrive in Cancun on a clear night. You look up at the stars and notice that they appear different that the
stars you see in Syracuse, NY. Which of the statements below is true regarding the appearance of the stars
in Cancun? Circle all that are true.
A) Polaris will appear higher in the sky than as seen in Syracuse.
B) The circumpolar region will appear smaller compared to its size in Syracuse.
C) Stars will complete one cycle in the same time as seen in Syracuse.
D) You can see stars in the southern sky that are not visible from Syracuse.
3) The long exposure image of star trails shown
below was taken while looking toward the east.
From which of the locations listed below was the
image obtained?
A) Sydney, Australia (Latitude 34 S)
B) Lima, Peru (Latitude 12 S)
C) Quito, Equador (Latitude 0 N)
D) Canary Islands (Latitude 29 N)
E) Berlin, Germany (Latitude 52 N)
EASTERN HORIZON
4) Which of the following locations is closest to the
north celestial pole?
A) RA = 14 h
dec = -85
B) RA = 0 h
dec = -43
C) RA = 23 h
dec = +43
D) RA = 14 h
E) RA = 8 h
dec = +85
dec = -2
5) Which of the following coordinates in your local horizon system (in Syracuse, NY at 43 N) is closest to the
zenith?
A) Az. = 180, Al. =43
D) Az. = 35,
Al. = 2
B) Az. = 273, Al. =52
E) Az. = 3,
Al. = 48
C) Az. = 90,
Al. = 90
6) Imagine that you are observing the stars at an observatory located outside El Paso, Texas (latitude =
32N). You may find the diagram below helpful.
S
N
A) At what altitude would Polaris appear above the northern horizon?
B) Would a star with a declination of +60 be circumpolar? Explain.
C) What would be altitude of the Celestial Equator looking south?
D) Would you be able to observe stars as far south as -50 declination? Explain.
E) Where would the celestial equator intersect the horizon?
Questions 7 and 8 below address the apparent motion of the stars as seen by an observer in El Paso, Texas. A
map of the United States below indicates the location of this city.
Syracuse, NY
El Paso, TX
7) If a particular star passed through the meridian in Syracuse, NY, how many hours before that same star
crossed the meridian in El Paso TX (see map at the beginning of the problem)?
A) 1 hr
C) 3 hr
E) 5 hr
B) 2 hr
D) 4 hr
8) In each of the boxes below, sketch carefully the apparent motion of the stars as seen in El Paso Texas
looking north, east and south. Include all quantitative information and timescales regarding the apparent
motions. Use the margins to record any notes regarding the apparent motions you think are relevant.
60
50
40
Altitude
30
20
10
Apparent Motion of the Stars Looking North
Apparent Motion of the Stars Looking East
Apparent Motion of the Stars Looking South
Answer the following six questions referring to the Whole Sky Map below.
All Sky Map
B
C
East
A
Celestial Equator
West
Ecliptic
D
12 Hr RA
6 Hr RA
0 Hr RA
18 Hr RA
12 Hr RA
9) What is the name of the point labeled C? ________________________________
10) When the Sun is at point B where will it rise along the local observer’s horizon? (Assume a northern
hemisphere observer.) Justify your answer using properties (rules) of the celestial sphere.
11) At which of the labeled points A through D will the Sun be above the horizon for the shortest time for an
observer at Syracuse, NY?
12) What is the declination of the Sun at the point labeled D? ________________________
13) At which of the labeled points will the Sun set to the south of west?_________________
The date is Dec 22. You observe that the Sun sets that day along the horizon as shown in figure below.
14) One week later will the Sun set at
A. the same location along the horizon,
B. to the right of the location shown above, or
C. to the left of the location shown above?
The image below illustrates the path of the Sun across the sky on three different days as seen from Syracuse,
NY.
A
B
East
C
South
West
15) Which of the paths labeled A, B or C, could represent the path of the Sun on Mar 22?
A) A
D) More information is needed to
B) B
answer the question
C) C
E) None of the above.
16) Which of the paths labeled A, B or C, could represent the path of the Sun the Winter Solstice?
A) A
D) More information is needed to answer the
B) B
question
C) C
E) None of the above.
17) Which of the paths labeled A, B or C, could represent a day with 9 hours of daylight?
A) A
D) More information is needed to answer
B) B
the question
C) C
E) None of the above.
18) The image to the right illustrates the shadow cast by a vertical pole
placed in the northern hemisphere of the Earth at noon on September
22. One week later, would the shadow cast by the pole be shorter, the
same length or longer? Explain in a few sentences.
To the Sun
The image below shows the Sun at the meridian.
Sagittarius
E
S
W
19) What constellation did the Sun rise in on the day the image above was taken?
A. Virgo
D. Ophiuchus
B. Libra
E. Sagittarius
C. Scorpius
20) We have presented in the class the concept of the Sun as a moving star to explain its apparent annual
motion. Equivalently, the apparent annual motion of the Sun could be explained by the real motion of the
Earth. In a few sentences explain why the solar day is a different length from the sidereal day using the
aspects of the real motion of the Earth.
21) The concept of the celestial sphere is ancient appearing in the oldest records of astronomical writings. In
spite of its ancient beginnings, the celestial sphere concept is still taught today as a core component in
celestial navigation classes for mariners and pilots. In a brief essay (10 to 20 sentences), describe the
celestial sphere. Include its “geography”, its relation to the Earth’s geography, its apparent motion and any
quantitative information pertaining to the apparent motion of the celestial sphere. Use the next page to write
your essay on.
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The Celestial Sphere Essay
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Name__________________________
Solve the following problems showing your work.
22) The average distance between the stars in the disk of the Milky Way galaxy is about 3.26 light years. How
many Suns could fit side-by-side in the average distance between the stars in the disk of the Milky Way
galaxy?
23) If the Earth were scaled down to the size of a golf ball (diameter = 4.27 cm), what would be the distance
from the Sun to Pluto (actual distance of 40 AU)?
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24) If astronauts were to travel to the nearest star past the Sun, Proxima Centauri, using a spacecraft that
travelled at commercial airliner speeds (1,000 km/hour or 278 m/s), how much time would be required to
make the journey? The distance to Proxima Centauri is 4.3 ly. Express your answer in seconds and in
years.
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Astronomy Formula and Constants Sheet for Exams
Conversions
Formulas
A
L

2D
360 
Main Sequence Lifetime t 
M
1010 yr
L
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