Star may appear fainter due to the interstellar medium. This effect is known as ____________________.
A)interstellar reddening
B)interstellar extinction
C)interstellar absorption line
D)interstellar dust

Question

Quizplus · Accepted Answer

Interstellar extinction is the dimming of a star's light as it passes through the interstellar medium, which includes dust and gas. This causes the star to appear fainter, and is also known as interstellar reddening since the interstellar dust tends to absorb blue light more than red light. Interstellar absorption lines are caused by specific wavelengths of light being absorbed by elements in the interstellar medium, while interstellar dust is the actual material causing the dimming. Therefore, option B (interstellar extinction) is the best choice.

Star May Appear Fainter Due to the Interstellar Medium