Reflection nebula are bluer than the stars that illuminate them. ...

[stock]

Reflection nebula are bluer than the stars that illuminate them. The Earth's sky is bluer than the Sun. Is this a coincidence? Explain why or why not.
 
  What will be an ideal response?

Question 2

What was the Ptolemaic model?
 
  A) an Earth-centered model of planetary motion published by Ptolemy
  B) the Earth-centered model of the cosmos in which the Earth was surrounded by seven perfect spheres, one each for the Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn
  C) a Sun-centered model of planetary motion published by Ptolemy
  D) the first scientific model to successfully predict solar and lunar eclipses

[Leostella20]

Answer to Question 1

Both arise for the same physical reason: blue light scatters more easily than red light, either by dust (as in reflection nebula) or by molecules (as in the Earth's atmosphere). Thus the red light passes more directly through the nebula, or the atmosphere, while the blue light scatters and gives the nebula, or the atmosphere, its bluer color. Therefore, it's no coincidence.

Answer to Question 2

A

[stock]

Excellent

[bblaney]

Gracias!