Comet C/2013 US10 (Catalina) on 2015-12-13
Images calibrated with bias, dark and flat in IRIS, registration on comet's motion in IRIS, noise reduction and intensity and saturation stretches in Photoshop CC. Its plasma tail is pointing upwards and its fan shaped dust tail is pointing downwards. An untrailed stellar object is seen to the upper right of the comet, which turned out to be a glint from Geosat Intelsat 706 (1995-023A, USSPACECOM #23571), identified by several fellows in the comets-ml group. The flash was so strong that it saturated the image.
m1 = 6.5, Dia. = 5', DC = 6, ~0.6 deg dust tail in p.a. 150 deg, 0.5 deg ion tail in p.a. 300 deg thru 20x80 binoculars visually. The comet was easily visible thru the binoculars, although it was strongly influenced by the zodical light.