--------------------------------------------- PLANET ANOMALY UPDATE 2005 #2-1 (issued 20-May, 14:40 UT) --------------------------------------------- PLANET observations over peak reveal finite-source effects Dear Colleagues, the full set of data collected by PLANET with the Danish 1.54m at ESO La Silla over the peak of the event OGLE 2005-BLG-158 / MOA 2005-BLG-17 taken between HJD=2453510.7526 (20-May, 6:04 UT) until HJD=2453510.9321 (20-May, 10:22 UT) show a more flattened light curve than compatible with a point source, therefore revealing finite-source effects. The same behaviour has been independently observed by OGLE. From a simple finite-source model (that needs some refinement), we estimate that the source moves by its radius in about 9 hours relative to the lens. With the source being a clump giant with angular radius ~ 5.7 micro-as (A. Gould, private communication), this implies a relative proper motion of ~ 15 micro-as/day. The finite-source model is now displayed on our light curve. More information about the nature of the event will result from PLANET data taken before the peak with the Canopus 1.0m near Hobart. Further dense observations are strongly encouraged. With the flattened peak, the magnification is still expected to be around 70. Event: OGLE 2005-BLG-158 / MOA 2005-BLG-17 RA (J2000): 18:06:04.24 Dec (J2000): -28:30:51.58 The baseline I magnitude reported by the OGLE team is 15.434. The baseline I magnitude reported by the MOA team is 15.68. For more information: PLANET: http://planet.iap.fr PLANET/RoboNet: http://star-www.st-and.ac.uk/~robonet/2005/micro_events.html OGLE: http://www.astrouw.edu.pl/~ftp/ogle/ MOA: http://www.physics.auckland.ac.nz/moa/ MicroFUN: http://www.astronomy.ohio-state.edu/~microfun/ -------------- 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.