Robert McNaught discovered over 50 comets, and this one was not the brightest, but it did barely reach naked-eye visibility during the month of June 2010. It was a good target for binoculars, and this image may approximate what one could see with ordinary binoculars. The comet displays a small green coma, and there may be a hint of a thin ion tail pointing upward.

This is not a good picture of the comet, partly because the pre-dawn sky was already getting bright when the exposures were made. But it does show the green color that was quite noticeable in binoculars or a telescope.

Image details: Three 90-second exposures at ISO 1600, taken with a Canon 400D camera and a telephoto lens at xx mm. 

June 18, 2010