1. A multiband spatial heterodyne spectrometer for determining spectra of incident light in at least a first and a second wavelength band comprising: a beam splitter configured to split incident light and to direct the incident light upon a first and a second diffraction grating, wherein the first diffraction grating is configured for Littrow reflection of incident light of the first wavelength band at least one first order and Littrow reflection of incident light of the second wavelength band at least one second order, wherein the second diffraction grating is configured for Littrow reflection of light of the first wavelength band at the first order and of the second wavelength band at the second order, and wherein light reflected by the first and the second diffraction grating forms interference patterns; an electronic camera for imaging the interference patterns, the camera comprising a detector having at least two rows of pixel sensors; a dispersive device selected from the group consisting of a prism and a diffraction grating for separating the interference patterns into interference patterns corresponding to the first and second wavelength bands; at least one anamorphic lens for imaging the interference patterns corresponding to the first and second wavelength bands a series of interferograms associated with different positions within the incident light on separate ones of the rows of pixel sensors; and a processing device coupled to receive information from the detector and to compute spectra therefrom.