This is part of an image that was made to record a spectrum of supernova SN2004dj in NGC2403. After I had introduced the spectrum to a german CCD-forum, someone asked wether there is a chance to extract some spectral features for a prominent HII-region in this galaxy. I tried it and here are the results. In the image above the HII-region is the hazy dot below the indicator on the left side. The supernova is the much brighter star to the right at the same distance form the mark.
Unprocessed spectrum, calibrated for wavelength. Prominent features are emission lines of hydrogen and oxygen. Hβat 4861Å, [OIII]??? at 5009 / 4959Å and Hα at 6563Å. I don't know yet what causes the peak around 5740Å?
Designation of this HII-region as region III (S44) is from
table from THE ASTRONOMICAL JOURNAL, 117:1249-1274, 1999 March, credits: L.Drissen, J.R.Roy et. al
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