Comet C/2020 M3 (ATLAS) was discovered on 27 June 2020 by the Asteroid Terrestrial-Impact Last Alert System (ATLAS), two telescopes developed by the University of Hawaii as an early warning system of a possible impact from an asteroid or comet. The comet reached perihelion on 25 October and was closest to Earth, at a distance of 53.6 million kilometres (between the orbits of Mars and Earth), on 14 November.
In mid-late November the comet passed through Orion and I took the opportunity to observe it on the evening of 18 November. In my 200 mm Celestron Edge HD it appeared as a fuzzy dot. In an hour or so of observation it climbed from 30° to 40° altitude and became noticeably brighter, but any coma that might have been present remained invisible, leaving just a tiny, fuzzy, moving blob.
I also used a driven stills camera with a telephoto lens of focal length 100 mm (approximately one-tenth that of the Edge HD) to capture this unimpressive object.
Original: Newsletter December 2020 Updated: 27 November 2020