The deposition of carbon nanotube (CNT) coatings via thermal chemical vapor deposition (CVD) is intensively reported. The surface acidity, chemical nature of the catalytic nanoparticles, and the carbon precursor are highly inter‐related key parameters. Furthermore, reducing the typical high‐growth temperature requires the implementation of toxic and hazardous organic precursors. In this study, the growth of CNT coatings is demonstrated using a single‐step CVD process in which magnesium oxides, material with enhanced basicity, and nanoparticles of cobalt are codeposited. This deposit catalyzes simultaneously the decomposition of ethanol to spark the growth of CNTs. The deposition is successively performed at 330–500 °C. Grown CNTs below 400 °C feature a high defect concentration and large diameters, 20 nm, relative to those obtained at ≥400 °C with no apparent defects and diameter of 12 nm. In terms of optical properties, films grown at ≥400 °C reflect less than 0.5% of light in the UV–vis–near IR, and exhibit a Lambertian behavior. Furthermore, the bidirectional reflectance distribution function measurements reveal identical optical properties irrespective of the underlying substrate. Therefore, the process holds a great potential for applications involving stray light reduction.

The European Space Agency (ESA), in collaboration with the European Commission (EC) and EUMETSAT, is developing a space-borne observing system for quantification of anthropogenic carbon dioxide (CO 2 ) emissions. Forming part of the EC's Copernicus programme, the CO 2 monitoring (CO2M) mission will be implemented as a constellation of identical satellites, to be operated over a period of at least 7 years and measuring CO 2 concentration in terms of column-averaged mole fraction (denoted as XCO 2 ). Each satellite will continuously image XCO 2 along the satellite track on the sun-illuminated part of the orbit, with a swath width of >250 km. Observations will be provided at a spatial resolution of 2 x 2 km 2 , with high precision (<0.7 ppm) and accuracy (bias <0.5 ppm). To this end, the payload comprises a suite of instruments addressing the various aspects of the challenging observation requirements: A push-broom imaging spectrometer will perform co-located measurements of top-of-atmosphere radiances in the Near Infrared (NIR) and Short-Wave Infrared (SWIR) at high to moderate spectral resolution

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The MetOp-SG 3MI mission is part of the EUMETSAT Polar System Second Generation (EPS-SG), an Earth observation Program for Operational Meteorology from Low Earth Orbit. It consists of two multi-spectral cameras, one operating in VNIR and one in SWIR. With 13 spectral channels between 410nm and 2130nm, including polarized channels, the instrument covers a semi-field of view of 57°. Due to tight stray-light specifications, on-ground calibration and post-processing correction are required. This paper covers the stray-light correction and calibration methods. The correction is indeed based on the on-ground measurement of Spatial Point Source Transmittance (SPST) maps. Due to the limited amount of maps which can actually be calibrated within a reasonable amount of time, an interpolation method was developed to deduce the stray-light behavior in the whole field of view of the instrument. Furthermore, dynamic range decomposition was required during the acquisition of the maps to get a high signal to noise ratio. Ray-tracing data from the 3MI optical model were used to evaluate the performance of the correction algorithm, including the contribution of SPST maps interpolation and acquisition errors.

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