Illustrate the satellites in outer space

Satellites in outer space transmit signals to Earth. Computers in vehicles (for example car, airplane or ship) receive and interpret these signals. Positioning relies on very accurate timing - atomic clocks are used due to their accuracy to within a fraction of a second per day. Every satellite transmits data indicating its time and position. Computer in the vehicle calculates its location based on the information from at least three satellites (in the case of airplanes, it's also possible to determine the position as well as height); this can be demonstrated diagrammatically as: