Download Astronomical Constants

SCI-103 Introductory Astronomy Exam #1 Spring 2014
Name_____________________
Class Meeting Time_____________
Grade Summary (To be completed by the Instructor)
HW #1_____________ (out of 20 points)
HW #2_____________(out of 40 points)
HW #3_____________(out of 25 points)
Quiz #1 ____________(out of 28 points)
Exam #1 ___________ (67 points total)
Grade So Far _______
Answer the following Multiple Choice Questions by circling the correct response.
1) During Spring Break you and your friends plan to travel north to Fairbanks, Alaska to see the northern
lights. You arrive in Fairbanks 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 Fairbanks? 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.
2) 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)
3) The Moon appears to cycle around the zodiac once every________.
A. 365.25 days
D. 24 hours
B. 29.5 days
E. 23 hours 56 minutes
C. 27.3 days
4) Which of the statements below about the apparent path of the Moon through the stars is the true statement?
A) The Moon drifts eastward through the stars on the ecliptic following the path of the Sun.
B) The Moon’s path through the stars is westward along the ecliptic completing once cycle every 365.25
days.
C) The Moon’s path through the stars is eastward closely following the ecliptic, but the Moon does not
return to exactly the same place in the sky after one sidereal period as the Sun does.
D) The Moon’s path through the stars is generally eastward, but is interrupted by occasional retrograde
motion.
The date is Mar 22. You observe that the Sun sets that day along the horizon as shown in figure below.
5) 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?
6) Imagine that you are observing the stars at an observatory located outside Washington, D.C. (latitude =
39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?
7) If a particular star passed through the meridian in Syracuse, NY (43N,76W), how many hours before that
same star crossed the meridian in Kiev, Ukraine (50N, 30E)?
A) 3 hr
C) 5 hr
E) 7 hr
B) 4 hr
D) 6 hr
Use the two images below, which were obtained from the Solar Heliospheric Observer (SOHO) spacecraft, to
answer the following question. The Sun is located behind the circle drawn on the mask and the bright object to
the right is a planet. The images were taken approximately four days apart with the earlier picture on top.
Eastward
Westward
Image obtained on May 12
Image obtained on May 16
8) The planet is approaching which of the planetary configurations listed below?
A. Maximum Elongation
C. Opposition
B. Conjunction
D. Quadrature
9) Put the phases of the Moon in chronological order, from earliest to latest, starting with waxing crescent.
A
Earliest: ______,
B
C
______,
______,
D
______,
E
______ : Latest
Questions 5 and 6 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
Miami, FL
10) In each of the boxes below, sketch carefully the apparent motion of the stars as seen in Miami, FL 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
11) What is the name of the point labeled B? ________________________________
12) 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.
13) At which of the labeled points A through D will the Sun be above the horizon for the shortest time for an
observer at Johannesburg, South Africa?
14) What is the declination of the Sun at the point labeled B? ________________________
15) At which of the labeled points will the Sun set to the North of west?_________________
16) If the Moon is at the position shown and the date is December 22, what phase is the Moon in?
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
17) Which of the paths labeled A, B or C, could represent the path of the Sun on Jun 22?
A) A
D) More information is needed to
B) B
answer 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 southern hemisphere of the Earth at noon on December 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
19) Which of the statements listed below best represents the apparent relationship between the Sun and the
Superior Planets?
A) The Superior Planets are never seen at opposition to the Sun.
B) The Superior Planets have a maximum elongation and appeared “tied” to the Sun.
C) The Superior Planets only go retrograde when in opposition to the Sun.
D) The Superior Planets only go retrograde when in conjunction to the Sun.
The image below shows the Sun at the meridian.
Sagittarius
E
S
W
20) 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
21) 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.
22) Lunar phase today is Waning Crescent. The moon is in the zodiac sign Cancer.
A) Approximately how days from today to the next Full Moon? __________
B) Approximately how many days from today will the Moon again be in the zodiac sign of
Cancer?_________
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23) Which of the angles listed below represents the maximum elongation of Venus?
A) 23½ 
C) 45
B) 28
D) 180
Solve the following two problems showing your work.
24) How many Earths could fit side-by-side in the distance between the Sun and Earth?
25) If the Sun were scaled down to the size of a golf ball (diameter = 4.27 cm), what would be the distance from
the Sun to the center of the Milky Way Galaxy (actual distance 28,000 ly))
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26) The sketch to the right shows the Moon in a certain phase.
A) Name the phase of the Moon shown. __________ ___________
B) Estimate the number of days till the next Full Moon
_______________ Days
C) Circle the position of the Moon on the diagram below that corresponds to the phase shown above.
Sun Light
Earth
27) Circle the seven planets of the ancient world from the alphabetic list presented below.
Earth
Jupiter
Mars
Mercury
Moon
Neptune
Pluto
Saturn
Sun
Uranus
Venus
28) In one sentence describe how these “planets” appeared to be different from all the other stars. (Two
differences are required for full credit)
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29) In the figure below label the positions of a planet at opposition, conjunction, quadrature and maximum
elongation. The position of the Earth (  ) and Sun (  ) are shown on the figure.


30) Use the graph provided below, on which an imaginary planet’s motion has been plotted over several
months, to answer the next question.
May 15th
Path of the
imaginary
planet
March 21st
April 22nd
March 1st
March 31st
April 12th
April 5th
80
100 120
140
160 180 200
60
55
50
45
40
35
30
25
20
15
10
5
220 240 260
31) For how many days would this planet have appeared to move with retrograde motion?
A) 10 days
A) 17 days
B) 12 days
B) 32 days
C) 15 days
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Astronomical Constants
Quantity
Value
astronomical unit (A.U.) 149,597,870.691 kilometers
light year (ly)
9.460536207× 1012 km = 63,240 A.U.
parsec (pc)
3.08567802× 1013 km = 206,265 A.U.
sidereal year
365.2564 days
tropical year
365.2422 days
Gregorian year
365.2425 days
Earth mass
5.9736× 1024 kilograms
Sun mass
1.9891× 1030 kg = 332,980 × Earth
mean Earth radius
6371 kilometers
Sun radius
6.96265 × 105 km = 109 × Earth
Sun luminosity
3.827× 1026 watts
Physical Constants
Quantity
Value
speed of light (c)
299,792.458 kilometers/second
gravitational constant (G)
6.6726× 10-11 m3 /(kg sec2)
Boltzmann constant (k)
1.380658 × 10-23 Joules/Kelvin
Stefan-Boltzmann constant () 5.67051× 10-8 J/(m2 K4 s)
Wien's law constant
2.897756× 106 nanometers Kelvin
Planck constant (h)
6.6260755× 10-34 Joules second
9.1093898× 10-28 grams
electron mass
= 5.48579903× 10-4 amu
1.6726231× 10-24 grams
proton mass
= 1.007276470 amu
1.6749286× 10-24 grams
neutron mass
= 1.008664904 amu
3.3435860× 10-24 grams
deuterium nucleus mass
= 2.013553214 amu
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