When radiation from an object passes through the interstellar medium:
A) the object appears dimmer
B) the object appears bluer
C) the object appears bluer and dimmer
D) the object appears redder and dimmer
E) the object's apparent velocity changes

Question

Quizplus · Accepted Answer

When radiation from an object passes through the interstellar medium, it undergoes a process called interstellar reddening. This is because the interstellar medium contains dust grains that scatter blue light more effectively than red light, which causes the object to appear redder. Additionally, some of the light may be absorbed by the dust, making the object appear dimmer. Therefore, the correct answer is D: the object appears redder and dimmer.

When Radiation from an Object Passes Through the Interstellar Medium