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Observation by Kevin Gurney: R Boo: Mira variable with emission lines

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Kevin Gurney


Kevin Gurney


2018 Mar 21 - 02:32


2018 Mar 23 - 18:33



  • Altair Astro 10in RC truss tube
  • Alpy 600 Spectrograph
  • Mesu 200 mount
  • Atik 460EX

12 x 120sec sub-exposures


West Sheffield

Target name

R Boo, HD 128609


R Boo: Mira variable with emission lines

About this image

R Boo is a Mira variable which has an interesting spectrum (class M8e). It shows the TiO molecular bands characteristic of class M but, more interestingly, shows emission lines at the Hydrogen Balmer series wavelengths. The spectrum attached was taken when the star was around magnitude 7.5-8 (best estimate from AAVSO website). The emission lines are clearly visible down to H9, but curiously H-epsilon is absent. Perhaps there is a nearby absorbtion line which blends with it to cancel it out?

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