EDP Sciences
Press Release
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Volume 493, Number 2, January II 2009
Page(s) L31 - L34
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:200811268
Published online 04 December 2008

A&A 493, L31-L34 (2009)
DOI: 10.1051/0004-6361:200811268


Ground-based secondary eclipse detection of the very-hot Jupiter OGLE-TR-56b

D. K. Sing1 and M. López-Morales2

1  Institut d'Astrophysique de Paris, CNRS/UPMC, 98bis boulevard Arago, 75014 Paris, France
    e-mail: sing@iap.fr
2  Carnegie Institution of Washington, Dept. of Terrestrial Magnetism, 5241 Broad Branch Road NW, Washington, DC 20015, USA
    e-mail: mercedes@dtm.ciw.edu

Received 31 October 2008 / Accepted 21 November 2008

We report on the detection of the secondary eclipse of the very-hot Jupiter OGLE-TR-56b from combined z'-band time series photometry obtained with the VLT and Magellan telescopes. We measure a flux decrement of 0.0363 $\pm$ 0.0091% from the combined Magellan and VLT datasets, which indicates a blackbody brightness temperature of 2718+127-107 K, a very low albedo, and a small incident radiation redistribution factor, indicating a lack of strong winds in the planet's atmosphere. The measured secondary depth is consistent with thermal emission, but our precision is not sufficient to distinguish between a black-body emitting planet, or emission as predicted by models with strong optical absorbers such as TiO/VO. This is the first time that thermal emission from an extrasolar planet is detected at optical wavelengths and with ground-based telescopes.

Key words: binaries: eclipsing -- planetary systems -- stars: individual: OGLE-TR-56 -- techniques: photometric

© ESO 2009