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Rosette close-up - Globulettes in IPHAS H-alpha survey data


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Here's a close-up of the chain of dark clouds of the Rosette Nebula using public domain data.

I've used IPHAS survey H-alpha as luminance with a colour layer derived from the Digitized Sky Survey red/blue channels (transformed to a SHO style turquoise/gold colour layer).

My own 8'' GSO RC version (last image below) was the inspiration (shown for low-res comparison).

Some people see "animals" formed from the dark clouds... I see a leaping jaguar top right (or spanner!) and an ostrich bottom left.

The tiny dark circles to the left of the jaguar's head are referred to as globulettes in Gahm et al (2007). The smaller circles are estimated to have masses of about 1-2 times that of Jupiter and a radius of about 2,000 AU and are speculated to result in the formation of free-floating interstellar planetary-mass objects.

-Photoshop (with Google Nik Collection for output sharpening and noise reduction)
-Defect cleaning from the IPHAS frames, stacking and mosaic re-mapping using my own software (which occasionally seems to work)
-Again, my own processing software to do the red/blue to SHO-style colour mapping and also to make a local contrast layer

Data acknowledgements:
-H-alpha survey from the 2.5m Isaac Newton Telescope (www.iphas.org/data.shtml), 120 second frames
-Red and blue from the ESO Digitized Sky Survey archive DSS2 (archive.eso.org/dss/dss)
-Star colours from GAIA DR2 Archive (gea.esac.esa.int/archive)

Unprocessed data here

Cheers, Sam




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