  We present H and Ks-band photometry bracketing the secondary eclipse of the
hot Jupiter TrES-3b using the Wide-field Infrared Camera on the
Canada-France-Hawaii Telescope. We detect the secondary eclipse of TrES-3b with
a depth of 0.133+/-0.017% in Ks-band (8-sigma) - a result in sharp contrast to
the eclipse depth reported by de Mooij & Snellen. We do not detect its thermal
emission in H-band, but place a 3-sigma limit on the depth of the secondary
eclipse in this band of 0.051%. A secondary eclipse of this depth in Ks
requires very efficient day-to-nightside redistribution of heat and nearly
isotropic reradiation, conclusion that is in agreement with longer wavelength,
mid-infrared Spitzer observations. Our 3-sigma upper-limit on the depth of our
H-band secondary eclipse also argues for very efficient redistribution of heat
and suggests that the atmospheric layer probed by these observations may be
well homogenized. However, our H-band upper limit is so constraining that it
suggests the possibility of a temperature inversion at depth, or an absorbing
molecule, such as methane, that further depresses the emitted flux at this
wavelength. The combination of our near-infrared measurements and those
obtained with Spitzer suggest that TrES-3b displays a near isothermal dayside
atmospheric temperature structure, whose spectrum is well approximated by a
blackbody. We emphasize that our strict H-band limit is in stark disagreement
with the best-fit atmospheric model that results from longer wavelength
observations only, thus highlighting the importance of near-infrared
observations at multiple wavelengths in addition to those returned by Spitzer
in the mid-infrared to facilitate a comprehensive understanding of the energy
budgets of transiting exoplanets.
