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Observation by Kevin Gurney: Carbon star spectral features

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Kevin Gurney


Kevin Gurney


2018 Oct 26 - 22:58


2018 Oct 30 - 23:16



  • Altair Astro 10in RC truss tube
  • LHires 600l/mm
  • Atik 460EX
  • MESU200 mount
  • Prism, Demetra, Isis

6 subs at 300s each


West Sheffield

Target name

WZ Cas, W Ori


Carbon star spectral features

About this image

I decided it would be refreshing to look at something  other than H alpha in Be stars for a change...

Richard Walker has a good section on Carbon stars in his Spectroscopic Atlas which inspired me to look at some of the highlights therein.

WZ Cas has strong Lithium absorbtion at 6708A (panel b), and an even stronger sodium absorbtion around 5890. This is in fact a doublet which is just visible (I think!) in my medium resolution spectrum (panel a)

In contrast, W Ori has no strong Lithium absorbtion (panel d), but has a complex of lines at the blue end know as Merrill Sanford bands, apparently due to Silicon dicarbide (SiC2) - see panel c

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