--------------------------------------------- PLANET ANOMALY ALERT 2005 #6 (issued 2-Jul, 11:55 UT) --------------------------------------------- OGLE 2005-BLG-331 likely to undergo caustic entry Dear Colleagues, earlier today, the OGLE collaboration reported a fast rise in OGLE 2005-BLG-331 in excess of 1 mag/hr and considered it to be due to a caustic entry. This alert caused us to collect data with the Danish 1.54m at ESO La Silla, confirming a rise by about 0.3 mag between HJD=2453553.8270 (2-Jul, 7:51 UT) and HJD=2453553.8887 (2-Jul, 9:20 UT) in rough agreement with OGLE data. We were not able to obtain a good reference frame yet for our preliminary data reduction and the observing conditions were far from optimal, so that they can only serve as indication at the time being. A fold-caustic entry model would prefer a caustic passage time of (6 +/- 2) hrs, with the leading limb entering at HJD=2453553.712 +/- 0.003 (2-Jul, 5:05 UT). This would mean that the caustic passage is about to finish NOW, with the trailing limb entering. In addition to the entry of the leading limb, this is a second phase of strong value for the measurement of limb darkening. A light curve plot and data files for this event are available on our webpage, which is frequently updated. Event: OGLE 2005-BLG-331 RA (J2000): 17:50:09.60 Dec (J2000): -29:36:41.2 The baseline I magnitude reported by the OGLE team is 19.002 +/- 0.004. For more information: PLANET: http://planet.iap.fr OGLE: http://www.astrouw.edu.pl/~ftp/ogle/ -------------- On behalf of the PLANET collaboration Martin Dominik %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% If you prefer not to receive further PLANET Anomaly Alerts, please send an e-mail to planet@iap.fr.