Sunday, 17th Feb 2019



Dec 15 2015

Comet C/2013 US10 (Catalina)

Comet C/2013 US10 (Catalina)

This past weekend (December 12-13) I headed out with some friends to a dark sky location in the Alps at almost 2000 m elevation. We spent two nights imaging/observing, which were partly ruined by thin cirrus clouds rolling over Northern Italy for most of the time.

Needless to say, Comet C/2013 US10 (Catalina) was one of my planned targets, but it turned out to be harder than expected to image, because of the cirrus clouds and the comet being quite low (~ 20°) above the eastern horizon. That’s why even a 50-minute exposure (guided on the comet’s head) barely shows the two tails: the ion tail (pointing at about 11 o’ clock) and the dust tail, pointing at about 4 o’ clock.

The image is B/W only because I concentrated on the luminance given the poor observing conditions: BTW, the raw frames are plagued by quite strong gradients. Some data: 5 x 10 min = 50 min. total acquired with a Moravian G2 8300 FW CCD through a Pentax 105 SDHF refractor; more data available in the caption (click on the image to bring up a slightly bigger version and the caption).