Astronomy current events question: dusty protoplanetary disks

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!)

Whitney Clavin, "Pulverized Planet Dust May Lie Around Double Stars," August 23, 2010
http://www.nasa.gov/mission_pages/spitzer/news/spitzer20100823.html

Hot dusty disks surrounding close binary star systems observed by the Spitzer Space Telescope may be caused by:
(A) disrupted star formation.
(B) magnetic field storms.
(C) planets that have collided.
(D) telescope software glitches.
(E) lack of liquid coolant.

Correct answer: (C)

Student responses
Sections 70178, 70186, 70200
(A) : 7 students
(B) : 9 students
(C) : 46 students
(D) : 0 students
(E) : 1 student