Comet 12P/Pons-Brooks is moving rapidly through Aries; in this image with a 200 mm lens, we are zoomed in enough so that Jupiter (off the image to the upper left) and Hamal (off the image to the lower right) do not show (zoom out).  We can barely make out the upright tail but the non-stellar nature of the head is obvious.  Even with just a 10 second exposure with a 200 mm lens, the green color of the doubly ionized Oxygen in the coma comes out clearly if you zoom in enough to the pixel level.