20141005

Astronomy quiz question: position of moon during October 2014 total lunar eclipse

Astronomy 210 Quiz 3, fall semester 2014
Cuesta College, San Luis Obispo, CA

Observers in San Luis Obispo, CA will see a total lunar eclipse in October 2014.[*] During the total lunar eclipse, the moon will be located in:
(A) the moon's umbra.
(B) the moon's penumbra.
(C) the moon's negative shadow.
(D) Earth's umbra.
(E) Earth's penumbra.

[*] http://eclipse.gsfc.nasa.gov/OH/OHfigures/OH2014-Fig03.pdf.

Correct answer (highlight to unhide): (D)

During a total lunar eclipse, light from the sun that illuminate the full moon would be completely blocked by Earth, when the moon is completely within Earth's "complete shadow," or its umbra. (Note that since the textbook shows but does not specifically name the moon's antumbra, it is referred to as the moon's "negative shadow" for the purposes of discussion in this class.)


Section 70158
Exam code: quiz03s8tE
(A) : 5 students
(B) : 2 students
(C) : 2 students
(D) : 23 students
(E): 7 students

Success level: 57% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.81

Section 70160
Exam code: quiz03n6n4
(A) : 5 students
(B) : 4 students
(C) : 1 student
(D) : 19 students
(E): 5 students

Success level: 57% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.49

No comments: