Space Map Projections #
One of the most recent developments in map projections has been that involving a time factor, relating a mapping satellite revolving in an orbit about a rotating Earth. With the advent of automated continuous mapping in the near future, the static projections previously available are not sufficient to provide the accuracy merited by the imagery, without frequent readjustment of projection parameters and discontinuity at each adjustment. Projections appropriate for such satellite mapping are much more complicated mathematically, but, once derived, can be handled by computer.
Several such space map projections have been conceived, and all but one have been mathematically developed. The Space Oblique Mercator projection, suitable for mapping imagery from Landsat and other vertically scanning satellites, is described below, and is followed by a discussion of Satellite-Tracking projections. The Space Oblique Conformal Conic is a still more complex projection, currently only in conception, but for which mathematical development will be required if satellite side-looking imagery has been developed to an extent sufficient to encourage its use.