Few everyday technologies have had the kind of revolutionary impact that the Global Positioning System (GPS) has. From civilians to the military, from precision scientific studies to urban planning and disaster risk estimation, GPS has significantly changed our expectations of where we are and our sense of place.
What is GPS?
The U.S. Department of Defence started the GPS programme in 1973 and launched the first satellite in 1978. The modern GPS satellite constellation consists of 24 satellites moving around the earth in six orbits. Each satellite completes two orbits in a single day. The overall programme has three main components: the space segment, the control segment, and the user segment.
