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AF Andromedae

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AF Andromedae

There are some reports that AF Andromedae (in M31 -- 00 43 33.08 +41 12 10.3) has brightned and maybe in an S Doradus type LBV outburst.  This is maybe supported by photometry I have myself from last September.  We need clear confirmation to make a report.

The sun angle on it right now (May 9) is terrible and getting better.  It is around 20 degrees above the horizon in the morning at the start of twilight.  But I know some of you are able to go all the way to the horizon with your scopes.  So on the off chance that someone can get images (in two or more filters) or spectra, they could be useful.  Spectra would be especially useful since the spectrum of an LBV changes in distict ways during a true eruption.

In mid-September (2016) AF And was V~ 16.7, B~16.8, R ~ 16.4, I ~ 16.4.   So it is NOT an easy target.  But keep in mind that with spectroscopy you can expose as long you can see it well enough to get the slit positioned and you do not need to stop at twilight.  Low resolution you would do spectral classification with is sufficient because during a true eruption the spectrum should change from a hot OB star to a F giant.  Any resolution that could pick up that difference is good.  A filter wheel grating spectrum might even be useful.

If you get images or spectra, I'd love to see them.  Contact me through the forum or

AF And Outburst Confirmed

See ATEL 10383

We are scheduled to get a spectrum with the LBT in the next few weeks.  (Sun angle is currently terrible but improving.) If anyone beats us to it, I'd be tickled pink to see it.  

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