Wednesday, July 11, 2018

North America Nebula and Pelican Nebula

The North America Nebula (left) and Pelican Nebula (right) are one(!) large emission nebulae in the constellation Cygnus.

(click on image for full resolution image)

This image consists of almost 25 hours of data (3 hours Ha, 9 hours SII and almost 13 hours of OIII).

The nebula appears four times the size of the full moon. It's real size is 50 light years in diameter - it's at a distance of 1800 light years from earth. It was "probably" discovered by William Herschel on October 24, 1786 - or by his son before 1933 (William Herschels notes weren't clear if he meant this particular nebula).

The big, black divider in the nebula is actually a dark dust cloud between the nebula and earth - the nebula itself is continuous. It visually splits the nebula in the two nebulae.


The nebula gets excited by the blue, super hot star HD 199579.


As many emission nebulae, the North America Nebula also has several regions of star formation. The most concentrated area is the so called Cygnus Wall:

This is the first image with my new Officina Stellare RH200 telescope on the 10Micron HPS 1000 mount. It took me a loooooong time to collimate and align the RH200 telescope and also quite a while to setup the 10Micron mount. But now I can image completely unguided (it's awesome that all the modelling algorithm and such is on the mount and not yet another piece of software on the computer - makes things much more simple and stable).

I also tried a few new processing steps:
  • I did Noise Reduction and stretching on the separate images before combining. This lead to an image that was much more balanced from the beginning.
  • I used AutoHistogram for stretching. Really liked it as it allowed very fine control of background and overall level.
  • I used the DarkStructureEnhance script to bring out more details in the dark dust lanes.