Astronomy current events question: solar system edge discovery

Astronomy 210L, Fall Semester 2009
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!)

Clara Moskowitz, "Mystery Emissions Found at Solar System Edge," October 15, 2009
http://www.msnbc.msn.com/id/33332042/ns/technology_and_science-space/

What did the NASA Interstellar Boundary Explorer probe recently find at the edge of the solar system?
(A) Rapidly deteriorating heliosphere.
(B) Large planetoid that will pass close by in late 2012.
(C) Ion trails left by the Pioneer 10/11 and Voyager 1/2 probes.
(D) Ribbon of energetic neutral particles.
(E) Diffuse shell of dark matter.

Correct answer: (D)

Student responses
Sections 70178, 70186, 70200
(A) : 3 students
(B) : 3 students
(C) : 6 students
(D) : 43 students
(E) : 0 students