| 摘要 |
A system for automatically mapping the surface of a celestial body is presented. A satellite in a near polar sun-synchronous orbit about the body includes two or three linear sensing photo-detector arrays mounted transversely to the satellite heading. With two arrays, both are oriented at the same angle to the geometric vertical, with one aimed forward and the other aft along the apparent track of the satellite. With three arrays, the third array is oriented downward toward the geometric vertical. Two of the arrays are used to sense the body surface with the satellite velocity providing continuous imaging. With rugged terrain, one angled array and the vertical array sense linear strips of the body disposed parallel to the apparent path of the satellite. With relatively flat terrain the angled arrays are used. Data is acquired by sensing the same elemental areas of strips from a first position in space with a first array, and once the satellite has moved to a second position, with the second array. The two satellite positions and an incremental area on the ground define an equipolar plane. The two arrays produce two data flows which, when corrolated, result in data representative of elevational information for each incremental area of each strip. The system allows near real-time mapping since the imaged areas being compared are included in an equipolar plane, making data correlation for topographic information a matter of comparing the two one-dimensional records.
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