The BepiColombo Laser Altimeter BELA and Tx Verification

Abstract

BepiColombo is a mission to Mercury. The launch is scheduled for 2014. Onboard will be the BepiColombo Laser Altimeter (BELA) which is being developed and built in collaboration of the University Bern, Switzerland and the German Aerospace Center (DLR) in Berlin. The instrument's task is the global mapping of the planetary surface from an orbit in up to 1000 km height above the planet. Therefore the technique of measuring the travel time of light to the surface and back is used. As the speed of light is known very accurately the distance (range) can be calculated very simply. Questions about for example the geological evolution of Mercury or about the tidal movements shall be resolved. Especially the work on the laser transmitter part of the instrument is done by the DLR. This includes design, development and integration of the components as well as verification of the units. Precise alignment of the laser and the receiver telescope are mandatory for the functionality of the instrument. Extensive testing will be performed to assure this in the harsh Mercury environment. A testing setup therefore is designed and built up at DLR site in Berlin Adlershof.