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1. Alcyone (Eta Tauri, η Tau, 25 Tau) in the Pleiades open cluster, spectral type B7IIIe+A0V+A0V+F2V.

This star is a multiple system, but my goal of observation was the H-alpha profile of the main component:

401996433_AlcyoneHalphaeng.thumb.png.2029b799dd880009ff8f6620ee493cdf.png

Horizontal axis scaled to radial velocity:

2125524127_AlcyoneHalphavelocity.thumb.png.ebf8ca718e56aca26261d34658abf39b.png

 

2. Pleione (28 Tau, BU Tau) also in M45, spectral type B8Vne, variable star, the brightness changes in range: 4.83 - 5.38 V. 

This is the faintest star, which I observed with using APO 107/700 & Low Spec spectrograph 1800 l/mm. 

It was difficult, but obervation was positive (high gain, exposure time 4 min):

723151601_PleioneHalphaeng.thumb.png.d20513f3a16e7f99d3ac2088de4f9d3f.png

 

3. Tianguan (Zeta Tauri, ζ Tau), spectral type B1IVe+G8III: (mark ":" according to the VSX database means uncertainty).

This is an eclipsing binary with variability type E/GS+GCAS, period is 133 d. The brightness changes in range: 2.80 - 3.17 V.

1084380017_ZetTauHalphaeng.thumb.png.0f8094920ee7833407d9ba028bcf7b11.png

 

4. Cih, Tsih (γ Cas), spectral type B0.5IVpe, variable star with a magnitude range of 1.6 to 3 V:

722519772_CihHalphaeng.thumb.png.52f978f2cf6c8a1c4ac1f1da2d8f5737.png

 

5. Alnitak (Zeta Orionis, ζ Ori), spectral type O9.5Ibe+B0III. Variable star with a magnitude range of 1.74 to 1.77 V.

Spectral lines have characteristic P Cygni profile, below H-alpha:

1998762564_AlnitakHalphaeng.thumb.png.b14ff3b48cfea9035d05f3dbce968f70.png

Edited by Bajastro
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    • By acr_astro
      Hi all,
      as well today the sun is shining brightly here. I set up the Lunt to have a look at it, at first just for observing. However, somehow I cannot resist and have to do a sketch This time I've chosen reddish pastels on grey paper to better catch the color of the view in the eyepiece.

      Telescope: Lunt LS50THaB600PT
      Eyepiece: Celestron X-cel 10mm
      Date & Time: May 15th, 2020 / 1400-1430 CEST
      Location: home terrace, Dusseldorf region, Germany
      Technique: red and orange Koh-i-Noor pastels and pastel pens on grey Canson Mi-Teintes pastel paper
      Size: 24 x 32 cm
      Clear (and sunny) skies!
      Achim
    • By Bajastro
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      The most important purpose of observing this binary system was to record the historical Ca II line (often called as CaK, 3933.66 Å).
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      These were the spectroscopic observations in the 19th century:



      Source: https://www.leosondra.cz/en/mizar/#b20

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      And animation showing the changes in this line:



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      Animation showing the changes in the sodium doublet:



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    • By Bajastro
      This system consists of two yellow giants having types G0III and G8III (some sources give K0III), similar masses and brightness. The orbital period of the components is 104 days.
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      Based on these observations, the spectral spread for both observations for the sodium line is 0.79 Å (0.079 nm) or 4 pixels, which gives a difference of radial velocities of 40 km/s.
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      I took the radial velocity of the Capella barycenter into account and I received this phase plot:

      The background is the plot of radial velocities from paper:
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      https://arxiv.org/pdf/1104.0342.pdf
    • By Bajastro
      Recently I observed profiles of hydrogen Balmer lines in Sirius spectrum with spectral type A. I used LowSpec spectrograph with 1800 l/mm diffraction grating and APO APM 107/700 on HEQ5 mount.
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      H-beta:

      H-gamma:

      H-delta & H-epsilon:

      I had some problems with stacking, so I used the best single frames in analysis.
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