NGC 6884 is a bright, compact, moderately high-excitation planetary nebula. The spectrum of NGC 6884 shows a classic planetary nebula spectrum. Strong Oxygen III lines and strong Hydrogen alpha. Based on the fact we see a slight Hydrogen gamma emission line, I think the slight shoulder on the left hand side of the oxygen spike is probably Hydrogen beta emission. It is interesting to note that the ratio of the intensity of Ha to OIII is a little less than half in this spectrum. In the NGC 7027 spectrum we find a much higher ratio. Perhaps NGC 7027 will appear slightly redder than NGC 6884. This image of NGC 7027 does indeed appear very red. This image of NGC 6884 does indeed appear greener. Mind you, the colour balance of the images is unlikely to be the same, so its impossible to conclude anything.
Resolution is 25.3Å per pixel.
I am not sure why I didn't take longer exposures... the small number of frames has resulted in a rather noisey spectrum.
Captured in k3ccdtools. Stacked in Registax. Saved as TIFF. Open in photoshop and rotated and cropped. Saved as Tiff. Open in IRIS and saved as FITS. FITS opened in analysed in VSpec
Exposure Details :
StarAnalyser 14x15s on 200mm @ F5 with SC3.5
Curdridge Observatory, Southampton,UK
Spectroscopy and vspec tutorial
NGC 7027 - Another spectrum of a planetary nebula
PK 64+ 5.1 Campbell's Hydrogen Star BD+30 3639
