The stellar occultation by Makemake on 2011 April 23

J. L. ORTIZ, B. SICARDY, M. ASSAFIN, A. ALVAREZ-CANDAL, V. D. IVANOV, J. CAMARGO, S. LITTLEFAIR, E. UNDA-SANZANA, E. JEHIN, F. BRAGA-RIVAS, E. LELLOUCH, N. MORALES, J. LICANDRO, R. GIL-HUTTON, R. DUFFARD, Y OTROS.

Nantes

Congreso; EPSC-DPS Joint Meeting 2011; 2011

Europlanet

We have taken advantage of a stellar occultation bythe dwarf planet Makemake on 2011 April 23, todetermine several of its main physical properties. Wepresent results from a multisite campaign with 8positive occultation detections from 5 different sites,including data from the 8-m VLT and 3.5-m NTTtelescopes in Chile, which have very high temporalresolution. Because the star was considerably fainterthan Makemake (setting a record in the magnitude ofa star whose occultation has been detected), theoccultation resulted in a drop of just ~0.3 mag in thelightcurves. From the lightcurves we have been ableto determine the size and shape of the body, itsgeometric albedo and constraints on its atmosphere.