Astronomy current events question: mapping the corona of black hole MAXI J1820+070

Astronomy 210L, spring semester 2019
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!)

Scott Wiessinger, Jeanette Kazmierczak, Erin Kara, and Aurore Simonet, "NICER Charts the Area Around a New Black Hole" (January 30, 2019)
svs.gsfc.nasa.gov/12854

Instruments aboard the International Space Station mapped the environment surrounding the black hole MAXI J1820+070 by detecting __________ originating from its corona.
(A) molten iron.
(B) cosmic rays.
(C) reflected x-rays.  
(D) neutrino emissions.
(E) gravitational waves.  

Correct answer: (C)

Student responses
Sections 30679, 30680
(A) : 0 students
(B) : 7 students
(C) : 19 students
(D) : 5 students
(E) : 12 students