CaSSIS (Colour and Stereo Surface Imaging System) is a camera conceived to acquire high resolution images of the surface of Mars. Thanks to a rotation mechanism, the CaSSIS telescope is able to acquire stereo image pairs which allow the 3D reconstruction of the planet surface.
CaSSIS is mounted on-board the ESA Exo-Mars Trace Gas Orbiter (TGO). TGO was launched in March 2016, and it reached Mars in the October of the same year; afterwards it has been subjected to aerobraking maneuvers to be finally inserted in its nominal 400 km-height circular orbit around the planet.
CaSSIS was designed and realized under the coordination of the principal investigator Nicolas Thomas from University of Bern in Switzerland. The Cnr-Ifn Padova has supported the CaSSIS team in Bern for the instrument alignment and calibration.
On 28 April, CaSSIS has officially started its nominal primary scientific mission. The camera was activated on 20 March to be tested for the beginning of its main mission. “While waiting for the images to come, you are asking yourself if the instrument carefully tested on-ground will be working properly in space too” says dr. Vania Da Deppo researcher from the Cnr-Ifn Padova and member of the CaSSIS Team. “We are really pleased to see how good are the pictures CaSSIS acquired during the instrument’s test period.”
An example of the obtained images is the spectacular view of the Korolev crater located high in the northern Martian hemisphere. The image is a composite of three images in different colours taken almost simultaneously by CaSSIS on 15 April. The three pictures were then assembled to produce the colour view. This image captures a 50 km-long segment of the crater and the bright material on the rim of the crater is ice.
Now that the most interesting phase of the mission is going to start, the CaSSIS team aims to fully automate the image production process; once this will be achieved, the data could be distributed quickly to the science community for analysis.
CaSSIS is an international programme led by the University of Bern (Switzerland) and carried on with the collaboration of the Italian Space Agency (ASI). The Italian responsible for the project is dr. Gabriele Cremonese from the Osservatorio Astronomico di Padova (INAF). The Italian company Leonardo S.p.A. located in Campi Bisenzio (Florence) was also involved for the detector and its electronics realization.
Vania Da Deppo
Cnr - Istituto di fotonica e nanotecnologie