Cloudy nights on hot Jupiters

International audienceThe atmospheres of hot Jupiters are inherently three dimensional and can be probed through the continuous observation of the planet brightness during it's orbit (aka phase curve). The phase curve amplitude and the offset of the maximum of the phase curve compared to the secondary eclipse is often used as a diagnostic of the day/night temperature contrast and the longitudinal shift of the hottes spot of the atmosphere. Current state-of-the-art global circulation models, however, systematically over predict the phase curve offset and underpredict the phase curve amplitude. Using a simplified cloud parametrisation we show that the presence of clouds on the nightside of the planet can affect both the phase curve offset and the phase curve amplitude, leading to a better agreement between data and theory