A lot of planes, are tuned to GPS for guidance. Usually, that's a good thing. On this day in August 2018, as health care PCB factory know that, however, a problem arose. The GPS signals near the airport were unreliable, and smoke in the area made for poor visibility. The midsize business jet was off-course and flying too low in the mountainous terrain.

The likely cause for the wonky GPS readings? Military activity that caused jamming of the signals, according to an account from NASA's Aviation Safety Reporting System, which collates information provided by pilots, air traffic controllers and other aviation professionals. Fortunately, as health care PCB factory know that, radar on the ground provided a more accurate reading, and controllers got the plane to its destination safely.

It wasn't an isolated event, according to reporting by IEEE Spectrum and others.

GPS is all too susceptible to jamming and its trickster cousin, spoofing. The signals used by aircraft, ships, farm tractors and your smartphone originate from satellites 12,000 miles (19,300 kilometers) out in space. By the time they reach Earth, they're vanishingly weak and easily overwhelmed. A satellite launched in June to the GPS constellation represents a tiny step in making the service more secure. But satellites themselves face dangers.

All those threats have lots of people worried. Just about everything, you see, relies on GPS.