Tonight, your telescope shows you RXJ1800, a galaxy, very near in the sky to the bright star Vega. What can you conclude from this observation?
A) RXJ1800 and Vega will drift apart from each other on the sky, over a matter of nights.
B) Vega and RXJ1800 must be very close to each other, less than a few light years.
C) Vega orbits the center of mass of RXJ1800.
D) RXJ1800 and Vega will set in the west, at very similar times.

Question

Quizplus · Accepted Answer

RXJ1800 and Vega appear near each other in the sky due to their positions relative to Earth, not because they are close in space. They will set in the west at similar times due to Earth's rotation.

Tonight, Your Telescope Shows You RXJ1800, a Galaxy, Very near in the Sky