A smudge near Jupiter I was looking at the Jupiter for the first time today and I have noticed a smudge near it. Could someone explain what it is, please? I was looking online but did not find anything. So I thought that some kind of defect in my setup but I couldn't get rid of it. I mean the thing below its moons. 

Edit1:
My telescope is a Celestron AstroMaster 76 ESQ. The smudge was there no matter what eyepiece I have used. I was able to see it even without a camera. 

Edit2:
I was watching it for about 10 minutes, and the smudge was moving along with the rest of the objects. 

I took just this one image for the StackExchange purposes. I have put the camera in front of an eyepiece to take the picture.

Thank you
The faint green smudge looks to me like a flare (that is, an optical defect called a flare).

However I'd expect a flare to be symmetric with the bright object it relates to about the center of the field of view.  This does imply either the image is off center (e.g. the camera is off center or the image is a crop off center) or there's a misalignment of your optics.

This question on Physics SE is about correcting flare in a telescope and may be relevant.

The similar question Does this smartphone photo show Mars just below the Sun? and its answers contain some other examples.