What is an artificial star?
A) a meteor
B) the unseen member of a binary star system
C) a satellite orbiting Earth
D) a point of light in Earth's atmosphere created by a laser for the purpose of monitoring atmospheric fluctuations
E) a possible source of dark matter in the universe
Question 2
Approximately how many neutrinos pass through your body each second?
A) about 1023
B) about a thousand trillion
C) about one thousand
D) None; they are blocked by the Earth's atmosphere.