Conceptual diagram of satellite triangulation. Not system used by Coast and Geodetic Survey.

Diagram showing conceptual photographs of satellite versus star background would appear from three different locations on the surface of the earth. For best results, satellites had to be observed from three camera stations simultaneously.

The worldwide satellite triangulation camera station network.

Conceptual planned method of tieing a worldwide satellite triangulation network together. The corners of the large polygons on the earth's surface were representations of BC-4 camera stations. Ideally the stations would be at least 1,000 miles apart and the apices of equilateral triangles.

A modified BC-4 satellite triangulation camera used in the world-wide triangulation program. The original BC-4 had a 350 mm focal length while the modified camera used in the program had a 450mm focal length.

The instrument system used in the satellite triangulation program. The large instrument consol on the left is the electronic synchronization unit while the modified BC-4 camera used for observations is on the right.

A global model of the satellite triangulation network.

System used to measure satellite locations relative to fixed star background. This operation was conducted in the office by photogrammetry experts. The plates were sent from camera stations around the world to headquarters for processing.

The satellite triangulation world-wide network. Notice void in Soviet Union and adjacent Communist bloc countries as the Cold War was at its height during these years.

Diagram used to explain theory behind satellite triangulation program.

Different colors on map display different phases of satellite triangulation program.

Typical photograph plate showing stars in circular pattern and satellite image showing as series of dots in straight line.

Inside of BC-4 camera showing shutter gears on upper portion of photo, lens in center, and various electronic connections for timing shutter opening and communicating with synchronization unit.

Map showing phase 1 densification network used to improve North American control network.

Diagram used to explain theory behind satellite triangulation program.

Electronic shelter on right used to house synchronization consol while the dome on the right was the camera dome for housing the BC-4 camera. The BC-4 is shown in operating position. A cover latches onto the opening when the camera is not in use.

6001 Executive Boulevard, Rockville, Maryland, designated the Washington Science Center. The home of the Coast and Geodetic Survey and the headquarters of the satellite triangulation program. This building was brand new at the time . It was razed in the late 1990's.

Station Number 001 -occupied 1/22/66 to 3/18/66 Party chief Sherrill Snellgrove of C&GS. Observations were conducted during the period when there were approximately 20 hours of darkness and 4 hours of twilight. As the PAGEOS satellites were in near polar orbit, this allowed observation of 4 to 5 passes per night.

Station Number 001 -occupied 1/22/66 to 3/18/66 Party chief Sherrill Snellgrove of C&GS The camera dome at Thule.

Station Number 001 -occupied 1/22/66 to 3/18/66 Party chief Sherrill Snellgrove of C&GS Installing a VLF antenna to aid with time signal reception. The synchronization unit was inside the warehouse.

Station Number 001 -occupied 1/22/66 to 3/18/66 Party chief Sherrill Snellgrove of C&GS Installing cables to connect VLF antenna to receiver in the the synchronization console in the warehouse.

Station Number 001 -occupied 1/22/66 to 3/18/66 Party chief Sherrill Snellgrove of C&GS 100 mph winds would drive snow into the camera dome in spite of dome cover and weather stripping being installed. Winds of this nature would freeze exposed human flesh in a matter of seconds.

Station Number 001 -occupied 1/22/66 to 3/18/66 Party chief Sherrill Snellgrove of C&GS Paul Spofford, assistant chief of party in the warehouse with synchronization console.

Loading a synchronization console on a truck for shipment at the Beltsville support facility.

Station Number 002 - occupied successively in 1964 and 1965 Party Chiefs, Charles Burroughs, Sherrill Snellgrove, and Bob Stevens

Station Number 002 - occupied successively in 1964 and 1965 Party Chiefs, Charles Burroughs, Sherrill Snellgrove, and Bob Stevens Hooking the "Goat" to the truck for shipment.

Station Number 002 - occupied successively in 1964 and 1965 Party Chiefs, Charles Burroughs, Sherrill Snellgrove, and Bob Stevens Lieutenant Dee Kimball, ESSA Corps, in truck and Charles Clarke loading a camera dome for shipment.

Station Number 002 - occupied successively in 1964 and 1965 Party Chiefs, Charles Burroughs, Sherrill Snellgrove, and Bob Stevens

Larry Schenkat, Chief of Timing Section, with a portable quartz crystal clock. It was used to check the mobile BC4 units' clocks.

Station Number 002 - occupied successively in 1964 and 1965 Party Chiefs, Charles Burroughs, Sherrill Snellgrove, and Bob Stevens Charles Clarke, Chief Electronics Technician, at Beltsville.

Station Number 002 - occupied successively in 1964 and 1965 Party Chiefs, Charles Burroughs, Sherrill Snellgrove, and Bob Stevens Chief Electronic Technician Jerry Reed.

Larry McClure, radio operator, and friend at going away party for Roy Anderson

Aerial view of BC4 support facility at Beltsville.

Station Number 002 - occupied successively in 1964 and 1965 Party Chiefs, Charles Burroughs, Sherrill Snellgrove, and Bob Stevens

Loading BC4 unit on a USAF C-124 cargo plane at Andrews Air Force Base.

Jerry Reed, Gale Rutstein, Dee Kimball, and Sherrill Snellgrove at the BC4 support facility at Beltsville.

Station Number 003 - occupied in 1965 and 1966 Party chiefs - George Cole, Slim Pickens, and Jeff Gammon. 47 11 7 North Latitute. 240 39 44 East Longitude.

Station Number 003 - occupied in 1965 and 1966 Party chiefs - George Cole, Slim Pickens, and Jeff Gammon. 47 11 7 North Latitute. 240 39 44 East Longitude.

Station Number 003 - occupied in 1965 and 1966 Party chiefs - George Cole, Slim Pickens, and Jeff Gammon 47 11 7 North Latitute. 240 39 44 East Longitude.

Station Number 003 - occupied in 1965 and 1966 Party chiefs - George Cole, Slim Pickens, and Jeff Gammon. 47 11 7 North Latitute. 240 39 44 East Longitude.

Station Number 004. 52 42 49 North Latitude. 174 07 26 East Longitude.

Station Number 004. 52 42 49 North Latitude. 174 07 26 East Longitude.

Station Number 004. 52 42 49 North Latitude. 174 07 26 East Longitude.

Station Number 004. 52 42 49 North Latitude. 174 07 26 East Longitude.

Station Number 004. 52 42 49 North Latitude. 174 07 26 East Longitude.

Station Number 004. 52 42 49 North Latitude. 174 07 26 East Longitude.

Station Number 004. 52 42 49 North Latitude. 174 07 26 East Longitude.

Station Number 006 - occupied 2/10/66 to 3/31/66. Party chief - Slim Pickens. 69 39 44 North Latitude. 18 56 28 East Longitude.

Station Number 006 - occupied 2/10/66 to 3/31/66. Party chief - Slim Pickens. 69 39 44 North Latitude. 18 56 28 East Longitude.