Abell 21, Imatra

Abell 21, or jellyfish mist, is a planetary-sized object in the constellation of twins. Although the object is large, it is unfortunately also dull in surface brightness, i.e. a challenging object of observation both visually and pictorially.

Maybe that’s why you don’t see new pictures of this very often.

I took this planetary first imaging set in 2017 and now 4v later a new attempt. Images were taken with C14 and H-alpha as well as OIII filters and composed as HOO color image. In black-and-white sub-images, the faint parts of the fog are better distinguished, which still extend beyond the field of view. Here’s a good subject for owners of a dark scene and a bright and slightly wider picture tube.

First image HOO color version. H-alpha in the red and OIII in the green and blue channels.

Another image of an h-alpha stack

in the third h-alpha stack as a negative, opaque areas stretched out

Fourth OIII stack

The fifth OIII stack is a stretched negative.

This description has been automatically translated from Finnish. Click here to see the original text.

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Newest observations

Contact information

Abell 21 - 19.3.2021 at 21.00 Imatra Observation number 96908