Abstract: A linearly extensible modular luminaire comprised of mounting tracks (100,180) and translationally offset overlapping channels (211,212), with incorporated luminous means, alone or along with hangers (331,332,731) that provide support for cover brackets (431,731) that are attached to light modifying coverings (400,900), and wherein linearly radiated light is distributed directly, or in combination with coverings indirectly or modified, when connected with a source of power and energized. Also, the modular luminaire that is not extensible but otherwise comprised of same components not translationally offset, permitting the construction of a wide variety of luminaires, such as the one in FIG. 11, that incorporates a canopy (150) for mounting over lighting outlet boxes.