page_title: Quill (satellite)
section_title: Flight path
hierarchical_section_title: Quill (satellite) / Flight path
caption_attribution_description: English: Swaths imaged Dec 1964 by U. S. "Quill" satellite radar.
context_page_description: Quill was an experimental United States National Reconnaissance Office program of the 1960s, which orbited the first synthetic aperture radar to produce images of the Earth's surface from space. Radar-imaging spacecraft of this design were not intended to be deployed operationally, since it was known that this system's resolution, inferior to that of concurrent experimental airborne systems, would not serve that purpose. Instead, the program's predominant goal was to show whether the propagation of radar waves through a large volume of the atmosphere and ionosphere would dangerously degrade the performance of the synthetic aperture feature.
  A detailed description of the program has been made available on-line by NRO.
context_section_description: Quill's first descending path crossed South America and reached its farthest south near Antarctica below the middle of the South Atlantic. The following ascent skirted Africa's east coast, then crossed Pakistan and the western tip of China near Alma Ata in the Soviet Union. Subsequent ascents followed paths of similar shape, but each one was “set over” to the west from the previous one by the amount of earth rotation in one orbital period plus a small amount of westerly orbit precession, for a total of 22.5°. Thus the second non-imaging ascent passed over the Caspian Sea, the third over western Turkey, the fourth near northern Italy's border with France, and the fifth over Ireland. The seventh ascent, the first one west of the Atlantic, went over Nova Scotia and Newfoundland, and the eighth was the first to reach the U.S. Midwestern states, where the initial imaging event took place.
  Sets of descending (southbound) paths at U.S. imaging latitudes occurred first over Pacific Ocean areas west of California and first occurred over eastern parts of the U.S. nearly a day later. After a substantial interval, a new set of northbound and then one of the southbound paths over the U.S. occurred, there being four such sets in four successive days, two of them then crossing previous ascending paths.  The last onboard recording of data on film occurred during the descending leg of the 30th revolution. That film was ejected and recovered over the Pacific Ocean during the descending portion of the 33rd orbit, after which only down-linked data were available. The final ground swath was imaged in the 72nd orbit, during which imaging ceased because the chemical battery providing system power became too discharged for continued payload operation.
  The longest (orbit 30) image swath stretched about 1000 miles (1600 km), a length limited by the maximum distance at which the satellite remained above the tracking station's horizon. The capture of data for that swath occupied only 3.6 minutes of orbit time.
caption: The swaths imaged December 1964 by U. S. "Quill" satellite radar.
exif: {}