[vsnet-alert 10202] V5579 Sgr fading update: red color

[Taichi Kato]

   V5579 Sgr fading update

   The present red color (B-V = +0.7) is unusual.  Nakajima-san's data
on May 7 had a color index of B-V = +0.43.  The reddening is likely
as a result of dust formation.  This early-stage fading is closely in
line with the phenomenon in V1280 Sco.  Spectroscopy and observations
at other wavelengths are encouraged.

  YYYYMMDD(UT)   mag  observer
  20080507.752  10.42V  (Kazuhiro Nakajima)
  20080507.756  8.84Rc  (Kazuhiro Nakajima)
  20080507.757  10.85B  (Kazuhiro Nakajima)
  20080507.759  10.69y  (Kazuhiro Nakajima)
  20080508.087    98  (Wolfgang Kriebel)
  20080509.005   102  (Pavol A. Dubovsky)
  20080509.2735 10.601V  (ASAS (Pojmanski, G. 2002, Acta Astron. 52,397))
  20080510.049   107  (Wolfgang Kriebel)
  20080511.3575 11.773V  (ASAS (Pojmanski, G. 2002, Acta Astron. 52,397))
  20080512.117   110  (Jose Ripero)
  20080513.145  120G  (Laurent Bichon)
  20080516.2746 <14.50V  (ASAS (Pojmanski, G. 2002, Acta Astron. 52,397))
  20080516.649  13.70V  (Kazuhiro Nakajima)
  20080516.666  11.62Rc  (Kazuhiro Nakajima)
  20080518.577  156B  (Peter Nelson)
  20080518.583  149V  (Peter Nelson)