MATS (Mesospheric Airglow/Aerosol Tomography and Spectroscopy) is a Swedish satellite mission scheduled for launch in 2019. MATS science focuses on mesospheric wave activity and noctilucent clouds. Primary measurement targets are O2 Atmospheric band dayglow and nightglow in the near infrared (759-767 nm) and sunlight scattered from noctilucent clouds in the ultraviolet (270-300 nm). While tomography provides horizontally and vertically resolved data, spectroscopy allows analysis in terms of mesospheric composition, temperature and cloud properties.

During 2017 the MATS instrument completed its critical design review and is now into its final phase of testing before the flight model of the instrument is built. In its final design the instrument will have one telescope with 6 channels, 2 in UV for measuring NLCs and 4 NIR channels for measuring the A-band. Each channel produces an image covering 250 km across-track and 40 km vertically at the with a resolution down to 5 x 0.2 km (horizontal/vertical) in tangent plane. Additionally the instrument will have one image channel and two photometers pointing in the nadir direction performing complementary measuremets of the airglow.

At this point performance tests have now been completed on a component level, and tomographic methods have been developed to effectivly convert MATS images into 3D fields of airglow and NLC brightness. Furthermore, modelling studies have been carried out to assess MATS ability to retrieve gravity wave structures from the O2 Atmospheric band.

The presentation will give an overview of the MATS mission, its goals, schedule and current status. It will discuss the design, and present the analysis and trade-offs leading to it, including results from straylight and imaging tests on a prototype telescope. It will also discuss the details on how to produce such 3 dimensional tomographic data within reasonable computaional constraints. Finally, it will give examples of the scientific data that MATS will produce including the quality we expect it to have based on the tests an analysis perfomed with the MATS prototype.