Images from the 5-Meter Telescope at Mount Palomar Are Not

Multiple Choice

Images from the 5-meter telescope at Mount Palomar are not as clear as they were when the telescope was first put into operation over 60 years ago. Why is this?

A) The quality of the mirror has degraded significantly over time.
B) Precession has changed the positions of a number of important targets so that they are no longer accessible from Palomar.
C) The telescope was recently damaged by an earthquake.
D) Light pollution has increased significantly in the past 60 years.