[vsnet-alert 23976] Re: omega Ori outburst?

[Taichi Kato]

Subject: Re: [vsnet-alert 23971] (fwd) Re: omega Ori outburst?
References: <E1j3B3d-0001Kz-HY at ori.kusastro.kyoto-u.ac.jp>
From: roberto nesci <Roberto.Nesci at iaps.inaf.it>

I am following Betelgeuse with a Canon 550D and 50mm Contax objective since 
december 27 until tonight February 16. Twenty comparison stars are taken from 
the HIPPARCOS catalog, in a magnitude range V_t 1.6-5.0. one of them being Omega 
Ori. Given the brightness of Betelgeuse, an exposure time of 5s at 100 ISO and 
F/5.6 is used: the average of 5-10 images is made and then the G channel is 
extracted for aperture photometry with IRAF/apphot. In no case Omega Ori 
(V=4.50) was deviant from the best fit line more than 0.08 mag; the rms 
deviation of the comparison stars from the best fit line ranged from 0.04 to 
0.08 mag. My observations do not support a brightening of Omega Ori. On the 
contrary, the dimming of Betelgeuse is quite evident.
-- 
prof. Roberto Nesci,  associated to Istituto Nazionale di Astrofisica,
(National Institute of Astrophysics) INAF-IAPS, via Fosso del Cavaliere 100, 
00133 Roma, Italia