French space program

Abstract: A large survey of the sky has been undertaken in the near u.v. in two different steps by the Laboratoire d’Astronomie Spatiale du Centre National de la Recherche Scientifique: 1. A wide field camera 120 x 80° survey programme on rockets began in 1967 and was continued by the launch of the Janus camera in 1972. 2. A medium field (6 x 8°) programme due to the S 183 French experiment on Skylab. The map shows the distribution of the S 183 fields on the celestial sphere, superposed with the two wide fields of the Janus camera (figure 1). A complementary work in visible light (H a) using similar wide field (60°) optics and very selective interference filters has been made during the same period in order to obtain an idea of the penetration in interstellar space of radiation below 912 A owing to ionization of the interstellar hydrogen considered as evidence of this radiation. The full set of these experiments in u.v. and H a gives a good synthetic figure of the extreme population I extension in the Milky Way.