Comet C2013US10 Catalina, 2015 (digital photo)

Creator: Gerald Rhemann The double-tailed comet structure is clearly illustrated in this breathtaking image of Comet Catalina. The white dust tail (on the right) streams in the opposite direction to the comet's path, while expelled gas particles are ionized by solar radiation and are strewn in the direction of the Sun's magnetic feild. Driven by the solar wind, the magnetic feild points away from the Sun and the ion tail (on the left) twists and turns to align with it. "There are some interesting technical requirements for photographing comets like this. Comets move against the background star feild, so recording the comet as a sharp object normally results in the stars 'trailing'. Conversely, if the stars are sharp, the comet will appear blurred. Here, through expert processing both the comet and stars are sharp. Just look at the fantastic detail in the comet's tail - quite superb!" Pete Lawrence Born digital photograph entitled 'Comet C2013US10 Catalina', by Gerald Rhemann, in Jaureling, Lower Austria, Austria Taken with a ASA Astrograph 8 -inch f/2.9 telescope, ASA DDM - 60 mount, FLI PL 16803 camera, multiple channels, 1.18-hour total exposure Runner-up winner in the Planets, Comets & Asteroids category, Astronomy Photographer of the Year 2016