Observing the surface of Venus with VIRTIS on Venus Express

Abstract

The M channel of VIRTIS will allow the first systematic mapping of the surface and of the near-surface atmosphere of Venus in the near infrared wavelengths range. This will be done using the atmospheric windows located at 1.10, 1.18 μm and if possible additionally using the window at 1.02 μm (Wattson and Rothman 1986, Kamp et al. 1988, Moroz 2002). The latter is unfortunately right at the low end of the wavelength range of the IR channel and at the upper end of the VIS channel. Therefore, the usability of this window is unclear until first data from Venus are obtained. The atmospheric windows will allow measuring the thermal emission of the surface as was demonstrated by Galileo/NIMS (Carlson et al. 1991) and Cassini/VIMS (Baines et al. 2000). Based on these data three main science tasks for the surface analysis will be pursued: Classification of the surface composition, study the interaction between low atmosphere and surface, and mapping of the variability of the surface temperature as a direct indicator for active volcanism. Therefore VIRTIS will be the first instrument to routinely monitor the surface of Venus for volcanic activity.