Prototype Hyperspectral Satellite Fast-Tracked to Begin Official Spy Work for Military | Popular Science

Prototype Hyperspectral Satellite Fast-Tracked to Begin Official Spy Work for Military | Popular Science: "Everything on the Earth's surface is being stimulated by energy from the Sun, and that causes everything to emit special spectral fingerprints. Hyperspectral sensors detect all those fingerprints. On board TacSat-3, complex computers sift through ARTEMIS' data, determining what the fingerprints represent and whether any of the objects or substances could be a target. There's no hiding from its prying eyes -- tricks that would defy optical or thermal sensors don't work with hyperspectral imaging."