[Aavso-photometry] Re: [AAVSO-DIS] 0749+22C Var NE Gem

[Richard Huziak]

0749+22C seems to be an irregular variable (type L?) with a range of 
about 11.7 - 12.7V.  No periodicity is evident from about 1 year's worth 
of CCD V-band data.  Current CCDV data shows the star at mag 12.1, and 
it is rising rapidly as it did a year ago.  Although a 1 mag range is 
ample to follow visually, with no comp stars between 12 & 13.1, most of 
the range is difficult for visual observers.  

However, the star is being 'adequately' covered by CCD observers (make 
sure your CCDV filter is turned on on the LCG to see the CCD data). 
 However, more observations are always very useful!  Although the star 
is marked "var" on the U Gem charts, I also find it strange that those 
who observe U Gem by eye or with CCD don't estimate or reduce for this 
star as well - lost opportunities for a known variable!  In the last 500 
days (more or less since this star was recognized as variable, it has 
received 656 observations - mostly CCDV observations by a few observers, 
whereas U Gem received 17,889 observations in 3 colour bands).   We 
could learn a whole lot about this star if the CCD guys went back into 
their archival images and re-reduced for +22C in 3-colours!  The same 
applies to hundreds of comp stars in other fields that are variable for 
(mostly) CCD observers.  See the Suspect Star Database under the Charts 
directory for guidance here.

I think I have CCD frames wide enough to check the Tycho star for you , 
Mike.   I'll get back to you in a few days on it.  The Henden dat file 
doesn't cover the star.

Rick (HUZ)

Michael Linnolt wrote:

>The newest charts (040225) for this variable and U Gem have no comp between 120 and 131. I suspect this may be one reason for the wide spread in estimates in the database. A CHET error report has been filed. One suggested comp is TYC 1375-1526-1 07 54 20.3 +21 57 24 V=12.42 B-V=+0.2 from tycho2+Bessell. Its about 11 arcmin west. Who knows of any photometry for this star? Is it constant?
>
>Mike Linnolt (LMK)
>
>----- Original Message -----
>From: "John A. Blackwell" <johnb at regulusastro.com>
>Date: Sunday, February 19, 2006 4:58 am
>Subject: [AAVSO-DIS] 0749+22C Var NE Gem
>To: 'AAVSO-DIS' <aavso-discussion at mira.aavso.org>
>
>  
>
>>0749+22C Var NE Gem has been steadily increasing in magnitude and 
>>looks like it might be headed for a peak. This is a plea for
>>observations. Since it is in the same field as U Gem, there are a 
>>lot of observations of this field star that could find their way
>>into the database. 
>>    
>>
>
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-- 

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Richard Huziak
Manufacturing Engineering
SED Systems
Saskatoon, SK, Canada
tel. (306) 933-1676
<huziak at SEDSystems.ca>
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