Can a Faint Star Be Detected If Its Counts Are Less Than the Noise Level?

[the riddick25]

Homework Statement

after subtracting the bias level from your count, you get a value of (N). to find the noise, you calculate sqrt(N) = noise.
now the question,
As above, your image has a noise of sqrt(N). What can you say about the presence of a faint star in the image that has a total number of counts that is LESS than sqrt(N)

Homework Equations

none

The Attempt at a Solution

i really haven't a clue about this question.
i would have guessed that its something like the sqrt(N) is an average value, so it is entirely possible for there to be a count less than that value.
but i don't know enough about the subject to make a decent guess at the question.


thanks

 

[Jhero]

for any help!

Hello, thank you for your post. It seems like you are on the right track with your understanding of the noise value being an average. The presence of a faint star with a total number of counts less than sqrt(N) suggests that the noise level is higher than the signal from the star. This could be due to various factors such as a low signal-to-noise ratio, background noise, or technical limitations of the equipment used to capture the image. Essentially, it means that the signal from the star is not strong enough to be detected clearly above the noise level. This could also indicate that the image needs to be processed or enhanced in some way to improve the visibility of the faint star.