Stock 21

Posted by dcrowson
on Sunday, December 24, 2017

Stock 21 is an open cluster located approximately 3,600 light-years away in Cassiopeia. The cluster is the small grouping of stars between the top and center of the image. I framed it this way to capture faint Sharpless 176 that didn’t show up at all in this image. This is one of 24 open clusters compiled by Jurgen Stock in the 1950s. A full list can be found here - (when and if the reference comes back online).

Luminance – 12x600s – 120 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2

240 minutes total exposure – 4 hours

Imaged from Dardenne Prairie, Missouri (a red zone) on December 12th, 13th and 20th, 2017 with a SBIG ST-8300M on an Astro-Tech AT90EDT at f/6.7 603mm.


My other Stock images can be found here -

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