Seminars at FGG

Investigation of the Venus thermal structure with VIRTIS/Venus Express

Speaker: Alessandra Migliorini (IASF-INAF, Roma)

Date and time: 2012-03-15 11:00

Atmospheric temperature of the night side of Venus is investigated using remote sensing data acquired with the VIRTIS (Visible and Infrared Thermal Imaging Spectrometer) instrument on board the European Venus Express mission, in orbit about the planet since 2006. The northern and southern hemispheres of the planet are explored in the pressure range from 100 to 4 mbar, which approximately corresponds to the altitude range from 65 to 85 km. The same behavior is observed on both hemispheres, though the coverage in the North is sparse because of the spacecraft orbit geometry. On the other hand, differences between the dusk and dawn sides are observed in the temperature values, the dawn being the coldest quadrant in the pressure range 100 to 12 mbar. The cold-collar feature is detected around 60-70° on both hemispheres. A peculiar pattern of maxima and minima in temperature is observed at 100 and 12 mbar. These features can be interpreted as indication of diurnal and/or semidiurnal thermal tides, as it results from the Venus global circulation model (Lebonnois et al., 2010b) of the Laboratoire de Météorologie Dynamique (LMD).