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As the only directly imaged multiple planet system, HR 8799 provides a uniqueopportunity to study the physical properties of several planets in parallel. Inthis paper, we image all four of the HR 8799 planets at H-band and 3.3 micronswith the new LBT adaptive optics system, PISCES, and LBTI/LMIRCam. Our imagesoffer an unprecedented view of the system, allowing us to obtain H and 3.3$micron photometry of the innermost planet (for the first time) and put strongupper-limits on the presence of a hypothetical fifth companion. We find thatall four planets are unexpectedly bright at 3.3 microns compared to theequilibrium chemistry models used for field brown dwarfs, which predict thatplanets should be faint at 3.3 microns due to CH4 opacity. We attempt to modelthe planets with thick-cloudy, non-equilibrium chemistry atmospheres, but findthat removing CH4 to fit the 3.3 micron photometry increases the predicted L'(3.8 microns) flux enough that it is inconsistent with observations. In aneffort to fit the SED of the HR 8799 planets, we construct mixtures of cloudyatmospheres, which are intended to represent planets covered by clouds ofvarying opacity. In this scenario, regions with low opacity look hot andbright, while regions with high opacity look faint, similar to the patchy cloudstructures on Jupiter and L/T transition brown-dwarfs. Our mixed cloud modelsreproduce all of the available data, but self-consistent models are stillnecessary to demonstrate their viability.

First Light LBT AO Images of HR 8799 bcde at 1.65 and 3.3 Microns: New Discrepancies between Young Planets and Old Brown Dwarfs