Astroart Forum

Clear sky today! I wanted to begin the year with some Be stars, now I'm taking high resolution H-alpha spectrum of Pleione (in the Pleiades asterism). Emission coming from an equatorial disk around the hot star (B8V spectral type) where hydrogen contained in it is excited by high energy radiation of the star. Be stars are very fascinating object, equatorial disk appear and disappear with time (the same happen to emission lines in the spectrum). The mechanism explaining the short, medium and long term spectral variations is not well understood by astronomers. So they ask amateurs to observe a great number of Be stars. Amateur spectra are collected, together with professional, in a specialized database curated by Paris-Meudon Observatory (http://basebe.obspm.fr).

Below a screen shot during Pleione spectra acquisition. I wish a serene and fruitful new year to all of you!

Paolo

Paolo,
Excellent stuff!!
(It's a funny experience to recognise the layout of the screen shot - just like mine!!)
I hope we can encourage others to take up the challenging, and satisfying area of spectroscopy.
Clear skies to all.

----------------
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before....
https://groups.yahoo.com/neo/groups/ast ... scopy/info
http://www.astronomicalspectroscopy.com/

Thank you Ken, effectively worldwide we use almost the same tools!

This experience was made with a high resolution spectrograph but I think is very important to know that a plenty of interesting observations (and related studies) can be also performed with a simple grating like the Star Analyser 100.

See you!
Paolo

PS: I reduced the spectrum, H-alpha intensities profile is plotted as a function of radial velocity. The rotation of equatorial disk around the star, tilted at a small angle to the line of sight, produces a broadening of emission line, here divided into two parts by central absorption (coming from stellar photosphere and disk).