Baker-Nunn Camera, by Smithsonian Astrophysical Observatory, c. 1958, Smithsonian Archives - History Div, Looking down on the Baker-Nunn Camera, one of the world's most sensitive devices for observing artificial satellites. A network of twelve tracking stations equipped with such cameras is maintained by the Smithsonian Astrophysical Observatory for the observation of both natural and artificial objects in space. The stations are located in Argentina, Australia, Curacao, India, Iran, Japan, Peru, South Africa, Spain, and at three sites in the United States..