How does the interstellar gas change the light of stars passing ...

[tnt_battle]

How does the interstellar gas change the light of stars passing through it, even if no dust is also present?
 
  What will be an ideal response?

Question 2

Why are emission nebulae ideal places to go hunting for brown dwarfs?
 
  What will be an ideal response?

[kjo;oj]

Answer to Question 1

Even the cool, thin atoms of gas will absorb some wavelengths of light, and these absorption lines will be very sharp, compared to the lines from the denser star's photosphere. So we can find the composition of the cool gases with these lines, and from their Doppler shifts, the motions of the gas clouds as well.

Answer to Question 2

These stellar nurseries give birth to a wide range of bodies of different masses, and those of less than 0.08 solar masses will heat up and glow red by gravitational contraction, but never get up to 10 million degrees to reach stage 7 and shine stably on the main sequence. In the Orion Nebula, several such submissive objects are noted.

[tnt_battle]

Thanks for the timely response, appreciate it

[AngeliqueG]

Excellent