Astronomy quiz question: Cancer and Pyxis centered above southern horizon

Astronomy 210 Quiz 1, spring semester 2019
Cuesta College, San Luis Obispo, CA

The diagram at right shows the southern horizon as seen by an observer at 12 AM in San Luis Obispo, CA. Ignore daylight saving time. What date is this?
(A) February 1.
(B) May 1.
(C) August 1.
(D) November 1.

Correct answer (highlight to unhide): (A)

As read off from a starwheel, Cancer and Pyxis will be centered above the southern horizon at 12 AM on February 1.

(On May 1 Cancer would be just above the west horizon at 12 PM. On August 1 Cancer and Pyxis would be centered above the horizon at 12 PM. On November 1 Cancer would be just above the east horizon at 12 AM.)

Section 30674
Exam code: quiz01n1aR
(A) : 23 students
(B) : 0 students
(C) : 12 students
(D) : 0 students

Success level: 66% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.23

Section 30676
Exam code: quiz01sRmB
(A) : 36 students
(B) : 0 students
(C) : 4 students
(D) : 0 students

Success level: 79% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50

Astronomy quiz question: Leo rising

Astronomy 210 Quiz 1, fall semester 2018
Cuesta College, San Luis Obispo, CA

The diagram at right shows the northeastern horizon as seen by an observer on January 5 in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see the stars in daylight. What time is this?
(A) 1:00 AM.
(B) 4:00 AM.
(C) 8:00 AM.
(D) 10:00 PM.

Correct answer (highlight to unhide): (D)

When Leo is placed above the northeast-east horizon on a starwheel, on the perimeter of the dial January 5 lines up with 10:00 PM.

Section 70158
Exam code: quiz01S1ri
(A) : 1 student
(B) : 4 students
(C) : 5 students
(D) : 28 students

Success level: 74% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.40

Section 70160
Exam code: quiz01nHa0
(A) : 0 students
(B) : 2 students
(C) : 0 students
(D) : 17 students

Success level: 89% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.20

Astronomy quiz question: Canis Minor rising?

Astronomy 210 Quiz 1, spring semester 2018
Cuesta College, San Luis Obispo, CA

The constellation Canis Minor is just above the east horizon, as seen by an observer at 9 PM in San Luis Obispo, CA. Ignore daylight saving time. What date is this?
(A) February 15.
(B) April 15.
(C) June 20.
(D) December 20.

Correct answer (highlight to unhide): (D)

As read off from a starwheel, Canis Minor will be just above the east horizon at 9 PM on December 20.

(At 9 PM Canis Minor will be high up in the sky, along the meridian on February 15; at 9 PM Canis Minor will be just above the west horizon on April 15; at 9 AM Canis Minor will be just above the east horizon on June 20.)

Section 30674
Exam code: quiz01n0rK
(A) : 1 student
(B) : 0 students
(C) : 3 students
(D) : 21 students

Success level: 84% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.43

Section 30676
Exam code: quiz01S1Bn
(A) : 2 students
(B) : 4 students
(C) : 4 students
(D) : 35 students

Success level: 78% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.39

Astronomy quiz question: last constellation to set

Astronomy 210 Quiz 1, fall semester 2017
Cuesta College, San Luis Obispo, CA

The diagram at right shows the positions at 11:00 PM of constellations Cygnus, Aquila, and Hercules as seen by an observer in San Luis Obispo, CA. Ignore daylight saving time. Within the next 24 hours, __________ will be the last constellation to completely set below the horizon.
(A) Cygnus.
(B) Aquila.
(C) Hercules.
(D) (There is a tie.)
(E) (None of these constellations will completely set below the horizon.)

Correct answer (highlight to unhide): (A)

As read off from a starwheel, Hercules is above the south horizon as shown at 11:00 PM on September 25. Advancing time forward (while keeping the date on September 26 once the time is after midnight) indicates that Cygnus will be the last of these three constellations to set, approximately eight hours later the following day.

Section 70158
Exam code: quiz01S3aN
(A) : 24 students
(B) : 9 students
(C) : 5 students
(D) : 0 students
(E) : 2 students

Success level: 51% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.39

Section 70160
Exam code: quiz01nMm5
(A) : 19 students
(B) : 1 students
(C) : 3 students
(D) : 0 students
(E) : 4 students

Success level: 61% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.44

Astronomy quiz question: time for Pisces to set

Astronomy 210 Quiz 1, spring semester 2017
Cuesta College, San Luis Obispo, CA

The diagram at right shows the positions on March 21 of the sun and the zodiac constellations Aries and Pisces for an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. On this day, the last part of the constellation Pisces will completely set below the horizon __________ later.
(A) three hours.
(B) six hours.
(C) nine hours.
(D) 12 hours.

Correct answer (highlight to unhide): (C)

As read off from a starwheel, Pisces is above the south horizon as shown at 12:00 PM on March 21. (Also since the sun is also centered on the south horizon, on the meridian, this must be 12:00 PM). Advancing time forward (while keeping the date at March 21) indicates that Pisces will completely set nine hours later that same day.

Section 30674
Exam code: quiz01nK0n
(A) : 0 students
(B) : 5 students
(C) : 17 students
(D) : 1 student

Success level: 76% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.17

Section 30676
Exam code: quiz01s7vN
(A) : 2 students
(B) : 10 students
(C) : 34 students
(D) : 1 student

Success level: 73% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.54

Astronomy quiz question: first star to set?

Astronomy 210 Quiz 1, fall semester 2016
Cuesta College, San Luis Obispo, CA

The diagram at right shows the positions on August 30 of the constellations Leo, Cancer, and Hydra for an observer in San Luis Obispo, CA. Also shown are the stars Regulus and Alphard. Ignore daylight saving time. Assume you can see stars in daylight. Within the next 24 hours, the star __________ will eventually set first, below the horizon.
(A) Regulus.
(B) Alphard.
(C) (There is a tie.)
(D) (Neither of these stars will set below the horizon.)

Correct answer (highlight to unhide): (B)

As read off from a starwheel, Regulus and Alphard will be above the east horizon as shown at 7:00 AM on August 30. Advancing time forward (while keeping the date at August 30) indicates that while they rose at about the same time earlier that day, Alphard will set first (around 4:30 PM), while Regulus will set approximately two hours later (around 6:30 PM) that same day.

Section 70158
Exam code: quiz01swE3
(A) : 9 students
(B) : 21 students
(C) : 3 students
(D) : 10 students

Success level: 50% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.25

Section 70160
Exam code: quiz01n4Ps
(A) : 7 students
(B) : 15 students
(C) : 4 students
(D) : 5 students

Success level: 47% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.34

Astronomy quiz question: Lyra will rise from which horizon?

Astronomy 210 Quiz 1, spring semester 2016
Cuesta College, San Luis Obispo, CA

The diagram at right shows the positions on February 14 of the constellations Cygus, Cepheus and Lyra for an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. After setting, the constellation Lyra will eventually rise on the __________ horizon.
(A) northeast.
(B) east.
(C) southeast.
(D) southwest.
(E) west.
(F) northwest.

Correct answer (highlight to unhide): (A)

As read off from a starwheel, Lyra will be just about to set on the northwest horizon at approximately 5:00 PM on February 14. Lyra will subsequently rise approximately 1:00 AM on February 15 from the northeast horizon.

Section 30674
Exam code: quiz01n0iR
(A) : 13 students
(B) : 4 students
(C) : 1 student
(D) : 1 student
(E) : 1 student
(F) : 1 student

Success level: 62% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.67

Section 30676
Exam code: quiz01sk4r
(A) : 34 students
(B) : 6 students
(C) : 3 students
(D) : 4 students
(E) : 1 student
(F) : 5 students

Success level: 65% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.53

Astronomy quiz question: time for Boötes to rise to zenith

Astronomy 210 Quiz 1, fall semester 2015
Cuesta College, San Luis Obispo, CA

The diagram at right shows the positions on September 1 of the constellations Ursa Minor and Boötes for an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. The constellation Boötes will be at its highest point in the sky __________ later.
(A) five hours.
(B) seven hours.
(C) nine hours.
(D) 12 hours.

Correct answer (highlight to unhide): (B)

On September 1 Ursa Minor and Boötes will have the positions shown above the north-northeast-east horizon at 9:00 AM. Using a starwheel to advance the time hourly starting from 9:00 AM on September 1, Boötes will be at the highest point in the sky (the zenith) at 4:00 PM, which is approximately seven hours later.

Section 70160
Exam code:
(A) : 6 students
(B) : 16 students
(C) : 2 students
(D) : 7 students

Success level: 52% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.76

Astronomy quiz question: time for Aquila to rise to zenith

Astronomy 210 Quiz 1, fall semester 2015
Cuesta College, San Luis Obispo, CA

The diagram at right shows the positions on September 1 of the constellations Cygnus and Aquila for an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. The constellation Aquila will be at its highest point in the sky __________ later.
(A) five hours.
(B) seven hours.
(C) nine hours.
(D) 12 hours.

Correct answer (highlight to unhide): (A)

On September 1 Cygnus and Aquila will have the positions shown above the northeast-east horizon at 4:00 PM. Using a starwheel to advance the time hourly starting from 4:00 PM on September 1, Aquila will be at the highest point in the sky (the zenith) at approximately 9:00 PM, which is five hours later.

Section 70158
Exam code: quiz01sC4r
(A) : 29 students
(B) : 2 students
(C) : 6 students
(D) : 8 students

Success level: 65% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.67

Astronomy quiz question: last zodiac constellation to set

Astronomy 210 Quiz 1, spring semester 2015
Cuesta College, San Luis Obispo, CA

The diagram at right shows the positions on April 25 of the zodiac constellations Sagittarius, Scorpius, and Libra for an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. Within the next 24 hours, __________ will be the last zodiac constellation to completely set below the horizon.
(A) Sagittarius.
(B) Scorpius.
(C) Libra.
(D) (There is a tie.)
(E) (None of these zodiac constellations will completely set below the horizon.)

Correct answer (highlight to unhide): (A)

Using a starwheel to advance the time hourly from 1:00 AM on April 25, Libra will completely set below the horizon at approximately the same as Scorpius, then Sagittarius will be the last to completely set approximately 10-11 hours later.

Section 30674
Exam code: quiz01nW0r
(A) : 23 students
(B) : 1 student
(C) : 7 students
(D) : 3 students
(E) : 8 students
(No response: 1 student)

Success level: 56% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.29

Section 30676
Exam code: quiz01Su8L
(A) : 24 students
(B) : 7 students
(C) : 11 students
(D) : 6 students
(E) : 7 students

Success level: 46% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.53

Astronomy quiz question: Cepheus to highest position in sky

Astronomy 210 Quiz 1, fall semester 2014
Cuesta College, San Luis Obispo, CA

The diagram at right shows the position of the constellation Cepheus as seen on December 31 by an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. Cepheus will be at its highest point in the sky __________ after the view shown at right.
(A) 5 hours.
(B) 7 hours.
(C) 9 hours.
(D) 12 hours.

Correct answer (highlight to unhide): (A)

Using a starwheel (planisphere), the sky as shown is 10:00 AM on December 31. Cepheus will be above Polaris at 3:00 PM on the same day, December 31, approximately five hours later.

Section 70158
Exam code: quiz01s7e8
(A) : 28 students
(B) : 7 students
(C) : 3 students
(D) : 4 students
(No response: 1 student)

Success level: 64% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.69

Astronomy quiz question: diurnal motion of sun versus zodiac constellations

Astronomy 210 Quiz 1, spring semester 2014
Cuesta College, San Luis Obispo, CA

[Version 1]
The diagram at right shows positions of constellations and the sun, as seen at 12:00 PM by an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. Which will set first on this date?
(A) The sun.
(B) Sagittarius.
(C) (There is a tie.)
(D) (Neither will set, as they are circumpolar.)

Correct answer (highlight to unhide): (A)

Generally objects low in the southern sky, located to the east of the meridian will set after objects that lie on or towards the west of the meridian. (This can be demonstrated using a planisphere (starwheel) for Sagittarius and Scorpius, as the sun would take approximately one month to move to the next zodiac constellation, and will remain within Scorpius during this date.)

Section 30674
Exam code: quiz01nYe3
(A) : 11 students
(B) : 6 students
(C) : 10 students
(D) : 3 students

Success level: 38% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.43

[Version 2]
The diagram at right shows positions of constellations and the sun, as seen at 12:00 PM by an observer in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. Which will set first on this date?
(A) The sun.
(B) Libra.
(C) (There is a tie.)
(D) (Neither will set, as they are circumpolar.)

Correct answer (highlight to unhide): (B)

Generally objects low in the southern sky, located to the west of the meridian will set before objects that lie on or towards the east of the meridian. (This can be demonstrated using a planisphere (starwheel) for Scorpius and Libra, as the sun would take approximately one month to move to the next zodiac constellation, and will remain within Scorpius during this date.)

Section 30676
Exam code: quiz01SLo3
(A) : 7 students
(B) : 32 students
(C) : 5 student
(D) : 1 student

Success level: 73% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.33

Astronomy final exam question: Comet C/2012 S1 ("ISON") just before perihelion

Astronomy 210 Final Exam, fall semester 2013
Cuesta College, San Luis Obispo, CA

An observing guide to spotting Comet ISON was published[*] before it fragmented and vaporized during its close pass to the sun. Explain how this diagram is consistent with the fact that Comet ISON was closer to the sun than Mercury[**] for late November 2013. Support your answer using a diagram showing the positions of the sun, Comet ISON, Mercury, and an observer on Earth.

[*] Joe Rao, "Comet ISON's Thanksgiving Sun Encounter: An Observer's Guide," November 23, 2013, http://www.space.com/23713-comet-ison-observers-guide-thanksgiving.html.
[**] "0.084 AU—Comet ISON’s forecasted distance from the sun on November 28, 2013, Mercury is 0.39 ± 0.09 AU from the sun," http://www.cometisonnews.com/distance/.

Solution and grading rubric:

• p = 20/20:
  Correct. Correct and complete diagram, with the sun, Mercury, Comet ISON, and an observer on Earth); shows and discusses how Comet ISON would be closer to the sun than Mercury on this diagram, consistent with the sunrise view given.
• r = 16/20:
  Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. Diagram and/or explanation has minor errors.
• t = 12/20: Contains right ideas, but discussion is unclear/incomplete or contains major errors. Problems with either diagram or discussion. At least understands that Mercury and Comet ISON must be just above the sun when the sun is at (or just below) a horizon.
• v = 8/20:
  Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Diagram and discussion problematic.
• x = 4/20:
  Implementation/application of ideas, but credit given for effort rather than merit. Misconceptions or non-relevant concepts.
• y = 2/20:
  Irrelevant discussion/effectively blank.
• z = 0/20:
  Blank.

Grading distribution:
Section 70158
Exam code: finals0oB
p: 15 students
r: 3 students
t: 10 students
v: 4 students
x: 4 students
y: 2 students
z: 1 student

A sample "p" response (from student 0527):

Astronomy midterm question: Cancer rising at 9:00 PM?

Astronomy 210 Midterm 1, fall semester 2013
Cuesta College, San Luis Obispo, CA

An observer in San Luis Obispo, CA watches the constellation Cancer rising at 9:00 PM. Ignore daylight saving time. What date is this?
(A) March 5.
(B) July 5.
(C) October 8.
(D) December 5.

Correct answer (highlight to unhide): (D)

Placing the constellation Cancer on the east/northeast horizon of a planisphere ("starwheel")--where it would be rising--then looking at the date that lines up with 9:00 PM shows that it is December 5.

(Response (A) is the date that Cancer would be highest overhead at 9:00 PM, and response (B) is the date that Cancer would be setting (on the west/northwest horizon) at 9:00 PM.)

Section 70158
Exam code: midterm1s73W
(A) : 8 students
(B) : 10 students
(C) : 0 students
(D) : 32 students

Success level: 66% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.59

Section 70160
Exam code: midterm1N1t3
(A) : 1 student
(B) : 12 students
(C) : 1 student
(D) : 16 students

Success level: 57% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.54

Astronomy quiz question: Camelopardalis from lowest to highest position in sky

Astronomy 210 Quiz 1, fall semester 2013
Cuesta College, San Luis Obispo, CA

The diagram at right shows positions of constellations and stars near the horizon, as seen at 9:00 PM by an observer in 
San Luis Obispo, CA. Ignore daylight saving 
time. Assume you can see stars in daylight. How many hours will pass 
until the constellation Camelopardalis 
reaches its highest point in the sky?
(A) 1 hour.
(B) 6 hours.
(C) 12 hours.
(D) 24 hours.

Correct answer (highlight to unhide): (C)

Using a starwheel (planisphere), the sky as shown is 9:00 PM on July 20 (or some other start time/date can be selected). Camelopardalis will be above Polaris at 9:00 AM on the next day, July 21, approximately 12 hours later.

Section 70158
Exam code: quiz01n9YE
(A) : 1 student
(B) : 7 students
(C) : 22 students
(D) : 1 student

Success level: 73% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.51

Astronomy quiz question: Arcturus setting versus Spica setting

Astronomy 210 Quiz 1, fall semester 2013
Cuesta College, San Luis Obispo, CA

The diagram at right shows positions of constellations and stars near the horizon, as seen at 8:00 PM by an observer in San Luis Obispo, CA. Ignore daylight saving time. 
Assume you can see stars in daylight. Which star will set first?
(A) Arcturus.
(B) Spica.
(C) (There is a tie.)
(D) (Neither star will set, as they are circumpolar.)

Correct answer (highlight to unhide): (B)

Using a starwheel (planisphere), the sky as shown is 8:00 PM on April 10 (or some other start time/date can be selected). Spica will set first at 5:30 AM the next day (April 11), while Boötes will set later at 8:30 AM.

Section 70158
Exam code: quiz01S0u7
(A) : 4 students
(B) : 37 students
(C) : 2 students
(D) : 3 students

Success level: 80% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.42

Astronomy quiz question: Ursa Major/Cassiopeia position

Astronomy 210 Quiz 1, spring semester 2012
Cuesta College, San Luis Obispo, CA

[Version 1]
Consider the view of the northern horizon shown below, as seen by an observer on February 2 in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. What time is this?
(A) 5:00 AM.
(B) 10:00 AM.
(C) 12:00 PM.
(D) 9:00 PM.

Correct answer: (B)

Response (A) has Cassiopeia at its lowest point in the sky on February 2; response (C) corresponds to the sky on January 1; and response (D) has Cassiopeia to the left (west) of Polaris on February 2.

Section 30676
Exam code: quiz01sH0p
(A) : 1 student
(B) : 39 students
(C) : 2 students
(D) : 6 students

Success level: 83% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.46


[Version 2]
Consider the view of the northern horizon shown below, as seen by an observer on February 2 in San Luis Obispo, CA. Ignore daylight saving time. Assume you can see stars in daylight. What time is this?
(A) 10:00 AM.
(B) 12:00 PM.
(C) 2:00 PM.
(D) 9:00 PM.

Correct answer: (A)

Response (B) corresponds to the sky on January 1; response (C) has Ursa Major at its lowest point in the sky on February 2; and response (D) has Ursa Major to the right (east) of Polaris on February 2.

Section 30674
Exam code: quiz01n3Wb
(A) : 27 students
(B) : 1 student
(C) : 0 students
(D) : 4 students
(No response : 1 student)

Success level: 79% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.22

Astronomy quiz question: low clockwise arc stars

Astronomy 210 Quiz 1, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

An observer in San Luis Obispo, CA notices over several hours that stars are making low clockwise arcs across the sky as they rise and set. Which horizon is this observer facing?
(A) North.
(B) East.
(C) South.
(D) West.

Correct answer: (C)

In San Luis Obispo, CA, an observer facing east or west would see stars rising or setting, respectively. An observer facing north would see stars making stars counterclockwise circles around the north celestial pole.

Section 30676
(A) : 16 students
(B) : 7 students
(C) : 24 students
(D) : 2 students
(No response : 1 student)

"Success level": 52% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.80

Astronomy midterm question: morning star Saturn?

Astronomy 210 Midterm 1, Fall Semester 2010
Cuesta College, San Luis Obispo, CA

[20 points.] Consider a popular online search (wordnetweb.princeton.edu) result for the definition of "morning star":

A planet (usually Venus) seen just before sunrise in the eastern sky.
--http://wordnetweb.princeton.edu/perl/webwn?s=morning%20star

Discuss whether it is possible or impossible for Saturn to also be a morning star, under this definition. Support your answer using a diagram showing the positions of the sun, Saturn, Earth, and an observer on Earth.

Solution and grading rubric:

• p = 20/20:
  Correct. Discusses the possibility of Saturn being in the eastern sky just before (or at) sunrise by drawing a heliocentric diagram with Saturn orbit larger than Earth's orbit, with Saturn near the opposite side of the sun (i.e., just after Earth and Saturn at conjunction), making Saturn visible to a morning observer, (slightly) higher above the same horizon as the rising sun.
  
• r = 16/20:
  Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. Draws Saturn at or just past conjunction, which would place it low in the eastern horizon at sunrise, but claims impossible to see due to brightness of the sun, or generally indicates where Saturn must be located along its orbit to be visible at sunrise, but does not sufficiently place near the eastern horizon.
  
• t = 12/20:
  Contains right ideas, but discussion is unclear/incomplete or contains major errors. Argues possibility or impossibility based on a diagram showing Saturn visible in the western horizon at sunrise, or visible in the eastern horizon at sunset.
  
• v = 8/20:
  Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Problematic diagram with Earth's orbit inside of Venus, Saturn's orbit inside of Earth's.
  
• x = 4/20:
  Implementation/application of ideas, but credit given for effort rather than merit.
  
• y = 2/20:
  Irrelevant discussion/effectively blank.
  
• z = 0/20:
  Blank.
  

Grading distribution:
Section 70160
p: 33 students
r: 1 student
t: 3 students
v: 3 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 3363):

Astronomy quiz question: sidereal motion (2)

Astronomy 210 Midterm 1, Fall Semester 2010
Cuesta College, San Luis Obispo, CA

An observer in San Luis Obispo, CA notices that the constellation Sagittarius is just above the southwest horizon at 9:00 PM on October 5. (Ignore the fact that your starwheel does not include daylight saving time.) Exactly 24 hours later, this constellation will be __________ the southwest horizon.
(A) slightly lower above.
(B) at exactly the same position above.
(C) slightly higher above.
(D) (None of the above choices, as it would not be visible anywhere in the sky.)

Correct answer: (A)

Using a starwheel (planisphere), the position of Sagittarius will shift slightly the next day, as seen by aligning 9:00 PM with October 5, and then aligning 9:00 PM with October 6, resulting in this constellation being slightly lower above the southwest horizon at the same time the next evening. This is caused by Earth's revolution around the sun while simultaneously rotating about its own axis. Response (B) would be true if Earth did not revolve around the sun, and only rotated about its own axis.

Section 70160
(A) : 22 students
(B) : 7 students
(C) : 11 students
(D) : 0 students

Success level: 59% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): -0.05

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• Astronomy quiz question: sidereal motion
  (Fall Semester, 2010).