Date: Sat, 13 Jul 2002 19:53:35 +0200 From: Gianluca Masi <gianmasi@fr.flashnet.it> Subject: [vsnet-chat 5380] Re: V4641 Sgr: observations from last night Dear Arne, thank you for your comments on the posted light curve. Unfortunately, I cannot check now the sequence, but I will do next monday. Anyway, I've posted on the web an image showing V, C1 and C2. As for C1, it looks a bit elongated, maybe for a close "companion". I measured the star as a whole. As for C2, it is well-located in the field, but its variability cannot be excluded. The field is at http://vsnet.bellatrixobservatory.org/v4641sgrcomp.gif Please note this is not an image from the run, as it was grabbed with a smaller telescope. The reason why I did the explicit plots for both V-C1 and V-C2 was to document any strange behaviour due to the differential atmospheric effects, because of the limited altitude of the target. I can reduce the data using different stars, to see how they will work. Regards, Gianluca Scrive aah@nofs.navy.mil: > At first glance, it looks like Gianluca's C2 is slightly variable. > Could you find the star in > http://ftp.nofs.navy.mil/pub/outgoing/aah/sequence/v4641sgr.d at > and let us know what the UBVRI magnitudes/colors are? Just as > a reminder to all observers, Bruce Sumner has created a photometric > sequence for this field, also found at > http://ftp.nofs.navy.mil/pub/outgoing/aah/sequence/sumner/v46 41sgr.dat > You will need to worry about blending/neighbors in this crowded field > if you want to do high-quality photometry. > Arne > -- *********************************************************************** * Gianluca Masi "Two things fill the soul * * Via Madonna de Loco, 47 with awe and reverence [...]: * * 03023 Ceccano (FR) the starry sky above me and * * ITALY the moral law within me" * * e-mail: gianmasi@fr.flashnet.it * * web: http://vsnet.bellatrixobservatory.org I. Kant * * Minor Planet Center Obs. Code: 470 - Ceccano * * Center for Backyard Astrophysics - Italy * * VSNET Collaboration Team member * * CCD-astrometry-photometry@yahoogroup.com mailing-list moderator * ***********************************************************************