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Astronomy quiz question: IAU classification of Earth's moon (with a moon?)

Astronomy 210 Quiz 4, spring semester 2014
Cuesta College, San Luis Obispo, CA

Listed below are the minimal qualifications established by the International Astronomical Union for a planet:
I. Orbits the sun.
II. Shape "rounded-out" by gravity.
III. Cleared/dominates orbit around sun.
In the (highly unlikely) event that Earth's moon were to capture a small asteroid such that it has a small moon of its own in orbit around it, which qualification(s) would change for Earth's moon?
(A) I only.
(B) II only.
(C) III only.
(D) Both I and II.
(E) Both II and III.
(F) Both I and III.
(G) I, II, and III.
(H) (None of the above choices.)

Correct answer (highlight to unhide): (H)

Even if Earth's moon would capture a small asteroid in orbit around it, Earth's moon still would not orbit the sun directly (qualification I); would remain rounded in shape (qualification II); and would still not dominate its orbit around the sun (qualification III); thus none of these qualifications for Earth's moon would be affected by Earth's moon being able to capture a small asteroid.

Section 30674
Exam code: quiz04n6rD
(A) : 2 students
(B) : 1 student
(C) : 4 students
(D) : 3 students
(E) : 0 students
(F) : 0 students
(G) : 1 student
(H) : 13 students
(No responses : 1 student)

Success level: 53% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.73

Section 30676
Exam code: quiz04snr7
(A) : 3 students
(B) : 6 students
(C) : 5 students
(D) : 2 students
(E) : 0 students
(F) : 1 student
(G) : 0 students
(H) : 22 students

Success level: 59% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.82

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