A method and a low-cost, robust and simple system for remote sensing and analyzing spectral properties of targets as a means to detect and identify them is introduced. The system can be highly portable but is usable in fixed locations or combination thereof. An aspect of the method and system includes the capability to distribute, modulate, aperture and spectrally analyze radiation emitted or absorbed by a volumetric target chemical species (solid, liquid or gas) or a target surface. Radiation is first collected by a single light gathering device, such as a lens, telescope, or mirror, and then distributed to multiple detectors through spectrally discriminating components and if desired through apertures to achieve this desired detection and identification.