The PRISMA (PRecursore IperSpettrale della Missione Applicativa) Programme is an ASI (Agenzia Spaziale Italiana)
hyperspectral mission for Earth observation based on a mono-payload single satellite: an Italian Consortium is in charge
to realize the mission; Selex ES has the full responsibility of the hyperspectral payload composed by a high spectral
resolution spectrometer optically integrated with a medium resolution panchromatic camera.
The optical design permits to cover the wavelength range from 400 to 2500 nm and it is based on high transmittance
optical assemblies, including a reflective common telescope in Three-Mirror Anastigmat (TMA) configuration, a single
slit aperture, a panchromatic camera (700-900 nm) and a spectrometer having two channels (VNIR and SWIR), each one
using an suitable prism configuration and spectrally separated by a beam splitter, conceived to minimize the number of
optical elements. High performance MCT-based detectors represent the core of the instrument. To provide the required
data quality for the entire mission lifetime (5 years), an accurate and stable calibration unit (radiometric and spectral) is
integrated, for the in-flight instrument calibration. The thermal design has been based on a passive cooling system: a
double stage radiator, suitable oriented and protected from unwanted heat fluxes, high performance heat pipes and an
operational heaters network represent the solution adopted to achieve the required thermal stability.