spectral

The electromagnetic spectrum extends from electric power at the long-wavelength end to gamma radiation at the short-wavelength end, covering wavelengths from thousands of kilometres down to fractions of the size of an atom. The spectra of radiation absorbed and emitted by matter is used to obtain information about matter. This kind of information is also used in remote sensing from satellites. Onboard scanners are equiped with sensors which digitally record images in separate spectral channels. Data from such spectral images are valuable in several environment analyses. Following are the main spectra bands from minimum to maximum wavelength.? = Gamma raysHX = Hard X-raysSX = Soft X-RaysEUV = Extreme ultravioletNUV = Near ultravioletVisible lightNIR = Near infraredMIR = Moderate infraredFIR = Far infraredRadio waves:EHF = Extremely high frequency (Microwaves)SHF = Super high frequency (Microwaves)UHF = Ultrahigh frequencyVHF = Very high frequencyHF = High frequencyMF = Medium frequencyLF = Low frequencyVLF = Very low frequencyVF = Voice frequencyELF = Extremely low frequency