Astronomy current events question: Gliese 710 close approach

Astronomy 210L, Spring 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, "Future Shock From Gliese 710," March 17, 2010
http://www.skyandtelescope.com/news/home/88198587.html

According to researchers, what is predicted to happen when the star Gliese 710 passes 1.3 light years from the sun roughly 1.5 million years from now?
(A) A slight increase in comet impacts on Earth.
(B) Disruption of Earth's orbit around the sun.
(C) A small probability that a binary star system will form.
(D) Massive tides on Earth.
(E) The night sky will no longer be dark enough to see other stars.

Correct answer: (A)

Student responses
Sections 30678, 30679, 30680
(A) : 16 students
(B) : 6 students
(C) : 2 students
(D) : 1 student
(E) : 1 student