From Sputnik to GPS: The Satellite Revolution That Redefined Our World

Psalm 19, verse 1 – “The heavens declare the glory of God; the skies proclaim the work of his hands.”

In 1957, a Russian satellite, Sputnik 1, was launched.  With this one satellite, an entire industry was born.  Today its’ uses have reached to all of our lives whether we have related work or are just sitting out in the wilderness enjoying Mother Nature.

In the communications industry, whole constellations of satellites have brought the world community instant contact.  Who would have thought that someone could phone home from the top of Mount Everest?  The cell phone has given added security to the community and aided in medical rescue operations.

In transportation, whole fleets of trucks as well as railroad shipping companies now rely on GPS to meet deadlines in providing materials and services to a growing nation.

These satellites look like crazed water heaters or enlarged winged insects and they fly about our heads 24 hours a day over 1000 miles around the earth.  These devices are crammed with all kinds of telemetry software and are launched at a cost of many millions of dollars.

Satellites can be just about any size and are restricted only by weight.  The heavier the satellite, the more costly and limited the mission.

What has occurred in the fields of cartography, geodesy, and remote sensing as a result of using satellites since the days of ONE STEP FOR MAN, ONE GIANT LEAP FOR MANKIND?

In October 1962 I went to work for the U.S. Army Map Service as a geodetic technician.   There we were trained to perform precision surveying on earth shape studies.  We left the good ole USA for months or a year at a time and took very costly and time-consuming field trips abroad.  Redundant observations were performed in the field while geodesists back in the home office reduced the data and double or triple-checked the final results.  These data were then run on a Friden calculator machine and transferred to punch cards to be fed to the mainframe computer for more analysis.

About 1997,  I became involved in the BC-4 project, a passive satellite system that used a camera that had been adapted to a Wild theodolite base and fitted with a glass plate to photograph a moving satellite against a star background.  Night observations were made on one of the launched satellite balloons that were in a low orbit.  These were good for short baseline and distance determinations.  When the worldwide satellite mapping mission started, we pointed our camera on Pegasus; a barely visible high-orbiting balloon that passed through the Big Dipper.  All these observations were very accurate but were limited to a clear night sky for two or more ground stations. This was the start of a new field of earth-shape determinations.

The present-day system is a constellation of 27 satellites known as the Global Positioning System (GPS.)   Satellites were launched from February 1989 until September 12, 1996.  The nominal operational constellation consists of 24 satellites and orbits the Earth every 12 hours.  This all works as (on a) a classroom doppler principle with a master control clock.  The precise ephemeris is available for less than centimeter results using one receiver.  The same results can be obtained using two or more receivers known as differential positioning.

So when you go outside and look up, you may not be able to see these winged metallic creatures following their set courses, day and night, but you can be assured that these civilization changes are here to stay.