Astronomy current events question: metal ions in Mars' upper atmosphere

Astronomy 210L, spring semester 2017
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!)

Bill Steigerwald and Nancy Jones, "NASA's MAVEN Reveals Mars Has Metal in its Atmosphere" (April 10, 2017)
nasa.gov/press-release/goddard/2017/metal-mars

Metal ions detected by NASA's MAVEN spacecraft detected in Mars' upper atmosphere may have come from:
(A) tiny meteoroids.
(B) its past volcanoes.
(C) the solar wind.
(D) the greenhouse effect.
(E) seasonal sandstorms.

Correct answer: (A)

Student responses
Sections 30679, 30680
(A) : 14 students
(B) : 6 students
(C) : 3 students
(D) : 0 students
(E) : 4 students