Space Photography and the Exploration of Mars
A contribution to [Applied Optics] by two members of the Mariner Mars '69 team, discussing space photography and planetary exploration. A figure of merit is derived that can be applied to the differing imagery of TV, earth photography, and space photography, based on the relative amount of information returned per unit area of the subject planet. As examples, this technique is used to compare the Mariner '71 TV system with a Lunar Orbiter system hypothetically orbiting Mars; the Lunar Orbiter camera yields 10 to 14 times more information at the Mariner's range limit (1500 km); also, it can work much closer to the Martian surface. Whole-disk spacecraft photos would just equal the best ground-based photography at a travel distance of 2-plus days from Mars, about 17 days from Jupiter, and 2-plus days from Mercury. Man willing, the next decade should be the flowering period of planetary exploration. 39 pp. Ref.