Approximately how many Global Positioning Satellites are above the horizon at any given time?

At any given time, a typical Global Positioning System (GPS) receiver can access signals from about 12 or more satellites above the horizon. This number is significant because GPS operates by triangulating the signals received from multiple satellites, allowing for accurate positioning and navigation calculations.

To achieve a reliable and precise location fix, a minimum of four satellites is necessary, but having access to 12 or more enhances the receiver’s ability to determine the user's position accurately, correct for errors, and provide additional data such as altitude and system integrity information. The geometry of satellite positions is vital; thus, redundancy in satellite signals improves the overall reliability and accuracy of the positioning system.

The other choices reflect a lower number of satellites than what is typically available, which may lead to less reliable positioning or inadequate satellite geometry for precise calculations.