Comet C/2021 Y1 Atlas and ?


I am sure this can be easily identified, but last night I set out to image comet C/2021 Y1 (Atlas), as according to SkySafari, it was supposed to be near star, Aldebaran.

I got that set of images but also noticed a green hue not far from it.  In fact, I thought the green hue was the comet but as I looked at recent Atlas images online I noticed it did not have that green hue.

Then I found what I think is actually Y1 Atlas in the same image so my question is, what is this green hue I captured?  I actually aligned on it and stacked it just like I did the Atlas image.


Below is image C1 and that is what I think is comet Atlas.

Image C2 show Atlas 'stacked' toward the middle (small), Aldebaran toward the top right, and the green hue, blurred like a star, toward the bottom left. This image helps show where they all are in relation to one another

Image G1 shows the green hue stacked and what appears to be a green coma around the nucleus.


At first I thought this is not a comet its something else, but in looking at the beginning and ending image sequence (about one hour), you can clearly see it moved, just like Atlas.

See image ‘G_move’ to see the first and last images of the night, of the green hue object.


Does anyone have any idea what this is? SkySafari does not show and I am not sure how else to tell.
I tried updating SF, but it still only shows Atlas in that area.

Image C1

Image C2

Image G1, stacked

Image G_move, single raw images (beginning and end) showing the movement in about one hour.



So it looks like this may be a reflection from Aldebaran. That green color threw me, though.
What would cause the reflection to be so green?