haracterisation and In-Orbit demonstration of a Heterodyne Spectrometer for atmospheric research from small satellites

This work presents the development of a new limb-sounder for temperature explorationof the upper atmosphere, the Atmospheric Limb Interferometer for Temperature Exploration (AtmoLITE). It is a miniaturized satellite instrument based around the technique of spatial heterodyne spectrometers. This class of spectrometers is well suited for miniaturization which allowed to design AtmoLITE within the formfactor of a 6U CubeSat. The observable of AtmoLITE is the rotational spectraldistribution of the day- and night-time oxygen atmospheric band emission, whichis particularly suited for temperature exploration from the lower most mesosphere towards the ionosphere. In addition, this work proposes a novel calibration conceptsuited to accurately characterise the AtmoLITE spectrometers spectral response.Major milestones achieved in this work were (1) the development of the optical system of AtmoLITE, (2) design of an appropriate calibration light stimulus, (3)experimental verification of AtmoLITE in-front of the calibration source, and (4) a first estimate of expected AtmoLITE temperature retrieval uncertainty.