The NOMAD instrument
NOMAD is a 3-channel spectrometer. 2 channels work in the infra-red and build upon the expertise of the Royal Belgian Institute for Space Aeronomy (BIRA-IASB) with its successful SOIR (Solar Occultation in the Infra-Red) instrument which is on-board ESA’s Venus Express mission (VEX). The 3rd channel works in the UV-visible range.
NOMAD’s solar occultation channel (SO) is a copy of SOIR/VEX. The Limb, Nadir and Occultation channel (LNO) is an improved version of SOIR, more adapted for fainter light sources as it will not only measure in solar occultation but also in nadir mode, i.e. looking directly at the sunlight reflected from the surface and atmosphere of Mars. The modified design includes a larger entrance slit to increase the amount of light entering the optics and a new acousto-optical tunable filter to maximise throughput. The UV-Visible channel (UVIS) is based on a design for a previous Mars lander made by the Open University, UK. It will measure in both solar occultation and nadir modes.
Below is a video showing the NOMAD design:
Three models of the instrument were built, as required by ESA:
NOMAD development and construction was carried out by the prime contractor, OIP, Oudenaarde, in collaboration with expert partners in Spain, the UK and Italy. The central electronics unit and firmware were designed by Spanish colleagues who worked on Rosetta, Mars Express and Venus Express, and were built by Thales Alenia Space Belgium (also known as ETCA). UVIS was designed and built by Lambda-X, Nivelles; its electronics were designed and built by the Mullard Space Science Laboratory, UK.
The Royal Belgian Institute for Space Aeronomy (BIRA-IASB) designed much of the SO and LNO channels, including the electronics and ground support equipment. The institute also managed all of the tasks carried out across Europe and maintained the documentation necessary for ESA. They also took care of the planetary protection aspects necessary for missions going to Mars, alongside their project management responsibilities. Testing and science performance were also the responsibility of the institute.