[vsnet-alert 13094] Re: DR UMa outburst!

Tom Krajci tom_krajci at tularosa.net
Tue Apr 5 22:07:18 JST 2011


An all-night time-series of this object showed a steady brightening of 
0.3 mag.

Casual visual inspection of the light curve may show faint hints of 
shorter periodicities, but I leave that to formal analysis by others.

I also took some short exposure BVRI images with a different telescope.  
I will see if stacking can make the target visible.  Perhaps these 
images will provide some useful color information?

Tom Krajci

================================================================

On 4/4/2011 9:51 PM, Brian Skiff wrote:
> On Mon, 2011-04-04 at 20:37 -0600, Tom Krajci wrote:
>> Initial unfiltered images from Astrokolkhoz (C11, 90 seconds) show an
>> object at J2000  13 59 05.77 +55 44 29.49 at approx unfiltered mag 17.
>>
>> At the SIMBAD coords for DR UMa (13 59 05.4 +55 44 04) approx 25 arcsec
>> away...nothing is detectable with a single image (fainter than mag 18?)
>
>       This links DR UMa with SDSS J135905.74+554429.3, whose
> position is:  13 59 05.74 +55 44 29.4  (J2000).  The Sloan proper
> motion is near zero.  The SDSS photometry is clearly for a very
> blue object, which would seem to make the ID certain, and thus the
> GCVS/VSX coordinates are in error.  No Sloan spectrum unfortunately.
> SDSS r magnitude = 20.00, presumably at quiescence.
>       Although the object is listed as a candidate quasar in various
> papers, I see no redshift determination from a _spectrum_ in the
> VizieR listing, only inference from colors and photometric redshift,
> which is obviously wrong.
>
>
> \Brian
>

-- 
-------------------------------------------
Tom Krajci
Cloudcroft, New Mexico
http://picasaweb.google.com/tom.krajci

Center for Backyard Astrophysics (CBA)
http://cbastro.org/ CBA New Mexico

American Association of Variable Star
Observers (AAVSO): KTC http://www.aavso.org/
-------------------------------------------


More information about the vsnet-alert mailing list