Astronomy current events question: Eris vs. Pluto

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

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)

Kelly Beatty, "Eris Gets Dwarfed (Is Pluto Bigger?)," November 7, 2010
http://www.skyandtelescope.com/news/106861063.html

Astronomers in Chile recently observed dwarf planet Eris __________, which may indicate that it is slightly smaller than dwarf planet Pluto.
(A) passing in front of a star.
(B) during a continent-wide power outage.
(C) eclipsed by Pluto.
(D) using infrared and radio waves.
(E) bombarded by an impactor.

Correct answer: (A)

Student responses
Sections 70178, 70186, 70200
(A) : 51 students
(B) : 2 students
(C) : 8 students
(D) : 2 students
(E) : 1 student