ngc 1023 and ic 239 in Perseus

[wimvb]

Two and a half larger galaxies and a bunch smaller ones. The spiral galaxy on the right is ic 239, the one and a half on the left are ngc 1023 and ngc 1023A. The latter is an irregular satellite galaxy to ngc 1023. It is ever so slightly bluer than its larger companion.

Also in the field of view are a number of smaller galaxies, many of which, quite unexpectedly, are closer by than ngc 1023 and ic 239. So they really are smaller.

Since ic 239 is a a spiral galaxy with active star formation, I decided to collect H-alpha as well as RGB. So far this image has a total integration time of 11  hours, of which 5 hours H-alpha and 6 hours RGB. During capture there was a layer of high cloud that softened the details, fwhm was 3.5 - 3.8 arc seconds.

As always, I used the SW 190MN with ZWO ASI294MM camera. Processed in PixInsight.

Edited January 7 by wimvb

[geeklee]

Lovely FOV @wimvb.  You've done well with NGC 1023A, a nice little faint cloud with the contrasting stronger blue you mention.  The Ha is subtle but worthwhile addition - very nice.

Edited January 8 by geeklee

[wimvb]

22 hours ago, geeklee said:

Lovely FOV @wimvb.  You've done well with NGC 1023A, a nice little faint cloud with the contrasting stronger blue you mention.  The Ha is subtle but worthwhile addition - very nice.

Thanks, Lee. Without that colour contrast, which was extremely faint, ngc 1023 would be just another blob. The small blue cloud makes a difference.