Alcatel-Space in hyper/multispectral Earth observation programs from MERIS to SPECTRA

ALCATEL-SPACE has been involved for years in the development of highest performance space optical payload for Earth observation, notably in the domain of multi/super/hyperspectral observation, through the successful development of VEGETATION (for CNES) and MERIS (for ESA). The paper will analyse how the lessons of the development of MERIS are key benefits for the definition of the next generation hyperspectral payload of the ESA SPECTRA mission. It will highlight the areas where a direct heritage is applicable, such as the calibration strategy, and domains where technology progresses allow major evolutions, such as for instance in the definition of the payload's data processing architecture. SPECTRA (Surface Processes and Ecosystem Changes Through Response Analysis) is one of the three candidate missions in the ESA Earth Core Explorer program of research oriented missions that is currently under phase A study. Its scientific objective is to describe, understand and model the role of terrestrial vegetation in the global carbon cycle and its response to climate variability under the increasing pressure of human activity.