The Energy Balance of Short-Period Planets - Nicolas Cowan (McGill University)

Most planetary systems do not resemble ours. Nature likes to produce planets between the sizes of Earth and Neptune, but located interior to Mercury's orbit. Since we have no analogs to these worlds in our Solar System, and since we do not yet have robust predictive models of planetary climate, we must observe them in order to understand their atmospheric composition, cloud formation, and winds patterns. By monitoring infrared emission as a function of orbital phase, we can infer a planet's Bond albedo, the efficiency of its day-night heat transport, and, in the case of planets subject to seasons, its thermal inertia. Multi-wavelength emission measurements also constrain atmospheric composition and vertical temperature structure. Such

inferences are particularly sensitive to the uncertainty in emission measurements, however, and the accuracy of eclipse measurements has typically been over-stated. Fortunately, improved analysis techniques and next-generation instruments should allow us to resolve outstanding questions about hot Jupiters, and to extend our methods to temperate terrestrial planets.