What features of the telescopic view of the Andromeda Galaxy, ...

[s.tung]

What features of the telescopic view of the Andromeda Galaxy, M-31, are also visible to the naked eye for our similar Galaxy?
 
  What will be an ideal response?

Question 2

The outflow channels on Mars indicate a flood period in the history of Mars. During this time, based on the width and depth of the remaining riverbed, it is thought that the flow rate must have been:
 
  A) just a small trickle, barely more than a stream of water.
  B) moderate, about the flow rate of the Ohio River.
  C) fairly large, about the flow rate of the current Colorado River.
  D) significantly large, about the flow rate of the Amazon River.
  E) enormous, as much as 100 times the flow rate of the Amazon River.

[Ahnyah]

Answer to Question 1

In Andromeda, we see a tilted disk of stars, which in our home Galaxy is seen as the band of light stretching across the sky as the Milky Way. We lie inside this disk, so the band appears fairly narrow. Dust clouds and spiral arms are visible in the disk of M-31, and we also can make out portions of three arms with the naked eye, and nearby dust clouds visually create gaps in the band of distant star light.

Answer to Question 2

E