2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/226375Assuming the features commonly ascribed to dark matter, we discuss our glimpse of the possibility that dark matter as a light transmitting medium played a role that accounts for the discordant inferences about the dynamical behaviour of light, in which some optical experiments cannot detect the earth's motion in space, while others definitely can. In a converse way, the mentioned laboratory and astronomical observations provide an accessible experimental proof for the existence of a transparent, non-baryonic earth-bound medium which does not occupy the whole of universal space, dark matter being a possible candidate medium.Some arguments improved in response to criticism and some references to earth-bound dark matter acknowledgedGeneral Physicstext