Astronomy current events question: searching for "Planet 9" in NASA Cassini data

Astronomy 210L, spring semester 2016
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!)

Julien Guillaume, "Searching for Planet 9" (February 23, 2016)
www2.cnrs.fr/en/2715.htm

Analysis of radio data from NASA's Cassini spacecraft may detect __________ perturbing Saturn's orbit.
(A) the sun's magnetosphere.
(B) dark matter.
(C) gravitational waves.
(D) cosmic background radiation.
(E) an undiscovered ninth planet.

Correct answer: (E)

Student responses
Sections 30678, 30679, 30680
(A) : 3 students
(B) : 2 students
(C) : 4 students
(D) : 5 students
(E) : 21 students