Calibration of Hyperspectral Imaging Data: VIRTIS-M Onboard Venus Express

Abstract

The Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS) is flying onboard the European Space Agency mission Venus Express and orbiting around Venus since April 11, 2006, providing very valuable remote sensing data of the planet. The instrument combines a double capability: a high-resolution imaging in the visible-infrared range (0.28-5 um) at moderate spectral resolution (VIRTIS-M channel) and a high-resolution spectroscopy in the 2-5 um range (VIRTIS-H channel). The scientific objectives of VIRTIS cover a large field and span from the study of the thermal emission of the surface up to the composition and dynamics of the upper atmosphere. The team is composed of people coming from institutes from more than ten countries. About 2.5 Gb of raw compressed data is coming, in average, every day from the spacecraft, which is to be further processed and distributed to the team for data analysis. This paper is meant to be a reference for all of the calibration processes performed on the hyperspectral images of the VIRTIS-M channel, which will be useful for the analysis of the measurements, to improve the interpretation of the final products and ultimately to reach a better understanding of Venus' atmosphere.