1. A multispectral omnidirectional optical sensor device comprising: an axisymmetric mirror providing a hemispherical field of view; one or more reflecting mirrors for splitting the electromagnetic spectrum into two or more electromagnetic wavelength bands; and a plurality of cameras spaced relative to the reflecting mirrors, wherein the number of cameras in the plurality is at least one greater than the number of reflecting mirrors, and wherein each camera senses one of the two or more wavelength bands and creates an image thereof so that each of the images is automatically registered.