How much fainter are the faintest stars you can see with a 10-inch telescope and a CCD camera that can integrate for 10 minutes compared to what you can see with your naked eye?
A) 30 billion times fainter
B) 30 thousand times fainter
C) 30 million times fainter
D) 30 trillion times fainter

Question

How much fainter are the faintest stars you can see with a 10-inch telescope and a CCD camera that can integrate for 10 minutes compared to what you can see with your naked eye?
A) 30 billion times fainter
B) 30 thousand times fainter
C) 30 million times fainter
D) 30 trillion times fainter

Quizplus · Accepted Answer

A standard 10-inch telescope has about 100 times the light-gathering power of the naked eye, and a 10-minute integration time with a CCD camera can increase the sensitivity by about 1000 times. Therefore, the telescope and CCD camera setup can see stars that are about 100,000 times fainter than what the naked eye can see. This corresponds to a factor of 30 million fainter (i.e. 10^5 * 10^3 = 10^8; 10^8 / 3.3 = 30 million).

How Much Fainter Are the Faintest Stars You Can See