title: Mars: correlation of optical and radar observations.
abstract: A comparsion of recent photographic and radar data on Mars indicates a good positive correlation between dark areas and radar reflection peaks and also between cloudy "desert" areas and radar minima. The data may be taken as evidence that dark areas are, in general, relatively smooth whereas deserts are relatively rough.
authors.forename: J C
authors.initials: JC
authors.lastname: Robinson