Astronomy quiz question: in the penumbra of the Moon

Astronomy 210 Quiz 2, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

[4.0 points.] An observer is located on the surface of the Earth, and this observer is also located in the penumbra of the Moon. What type of eclipse is seen by the observer?
(A) A total lunar eclipse.
(B) A partial lunar eclipse.
(C) An annular solar eclipse.
(D) A partial solar eclipse.
(E) A total solar eclipse.

Correct answer: (D)

Assuming that the umbra of the Moon never does pass over the observer (for which this would be response (E), a total solar eclipse), this will be only a partial solar eclipse. If the observer were in the "negative shadow" of the Moon (out past the umbra), then an annular solar eclipse would be observed (response (C)). Responses (A) and (B) correspond to the Moon itself being in the umbra or penumbra of the Earth, respectively.

Student responses
Section 70160
(A) : 5 students
(B) : 10 students
(C) : 0 students
(D) : 15 students
(E) : 3 students

"Difficulty level": 51%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.78