20180310

Astronomy midterm question: waxing moon rising at night after dinner?

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

The following excerpt from a novel[*] describes a rising moon:
Jane Ann Holder took her time going home after dinner. Everything about the night was fraught with memory and emotion. Turning on Van Buren Street, she saw a waxing moon rise over Deeds Hill.
Discuss why this description would be implausible, and how you know this. Support your answer using a diagram showing the positions of the sun, the moon, Earth, and an observer on Earth, along with any assumptions that you may have made.

[*] James Howard Kunstler, The Witch of Hebron, Grove/Atlantic (2010), p. 31.

Solution and grading rubric:
  • p:
    Complete diagram and reasoning, and thus concludes that a waxing moon cannot be seen rising at night (6 PM-6 AM) going home after dinner (5 PM-9 PM?). May instead demonstrate that only a waning moon would be able to rise at night.
  • r:
    Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors.
  • t:
    Contains right ideas, but discussion is unclear/incomplete or contains major errors. May have based argument on highest overhead instead of rising times, and/or may have rising time six hours after highest overhead time instead of six hours before.
  • v:
    Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. At least attempts to draw a moon phase diagram and apply rise/overhead/set times.
  • x:
    Implementation/application of ideas, but credit given for effort rather than merit. Discussion not clearly based on a moon phase diagram.
  • y:
    Irrelevant discussion/effectively blank.
  • z:
    Blank.
Grading distribution:
Section 30674
Exam code: midterm01nND4
p: 13 students
r: 1 student
t: 3 students
v: 4 students
x: 4 students
y: 0 students
z: 0 students

Section 30676
Exam code: midterm01sNuB
p: 25 students
r: 3 students
t: 9 students
v: 8 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 3825):

Another sample "p" response (from student 2025):

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