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arXiv · 1001.2017

Spatially resolved spectroscopy of the exoplanet HR 8799 c

M. Janson·C. Bergfors·M. Goto·W. Brandner·D. Lafreniere
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Abstract

HR 8799 is a multi-planet system detected in direct imaging, with three companions known so far. Here, we present spatially resolved VLT/NACO 3.88--4.10 micron spectroscopy of the middle planet, HR 8799 c, which has an estimated mass of ~10 Mjup, temperature of ~1100 K and projected separation of 38 AU. The spectrum shows some differences in the continuum from existing theoretical models, particularly longwards of 4 microns, implying that detailed cloud structure or non-equilibrium conditions may play an important role in the physics of young exoplanetary atmospheres.

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M. Janson, C. Bergfors, M. Goto, W. Brandner, D. Lafreniere. 2010-01-12. Spatially resolved spectroscopy of the exoplanet HR 8799 c. https://doi.org/10.1088/2041-8205%2F710%2F1%2Fl35

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