Question
Explain how GPS works in 2-3 sentences by using these paragraphs
Global positioning systems (GPSs) have become a major part of our daily lives. They make things easier when we are traveling through unfamiliar places or when we get lost. A GPS can tell you your location, speed, and altitude, whether you are driving a car, traveling on foot, or piloting a plane or boat. Most smartphones have GPS features, and a countless number of apps use this technology. But just how does GPS work?
The Trilateration Process
There are 24 satellites in outer space, orbiting the Earth twice a day from over 12,000 miles above the planet's surface. They are positioned such that no matter where you are, at least four satellites can "see" you at any given time. These satellites send signals that travel at the speed of light until they reach your GPS device. The device then calculates how far away each satellite is based on how long it took their signals to arrive.
Once your GPS device knows how far away at least three of the satellites that are "watching" you are, it can use a process called trilateration to determine exactly where you are. To understand how trilateration works, picture three satellites in the sky above where you are standing. Now picture each satellite as having a "circle" around it that represents its scope of sight. If you know your distance from each of the three satellites, you can determine that your location is where the satellites' circles intersect. Of course, if there are more than three satellites that are "watching" you, your GPS will give you a more accurate location.
Developed for Military Use
The technology behind the GPS was originally developed by the U.S. government. The first satellite was launched in 1978, and by 1995 all of the current 24 satellites were up and operating. It cost an estimated $10 billion to build this system and $400 million per year to maintain it. The solar-powered satellites are built to last 10 years before needing replacement.
While originally intended for military use, today anyone with a GPS device can receive the satellites' radio signals. In 2000, the system was opened to the entire world because President Bill Clinton believed that it would be more useful in that capacity. And he was correct; to many people throughout the world, it's hard to imagine life without it.
Global positioning systems (GPSs) have become a major part of our daily lives. They make things easier when we are traveling through unfamiliar places or when we get lost. A GPS can tell you your location, speed, and altitude, whether you are driving a car, traveling on foot, or piloting a plane or boat. Most smartphones have GPS features, and a countless number of apps use this technology. But just how does GPS work?
The Trilateration Process
There are 24 satellites in outer space, orbiting the Earth twice a day from over 12,000 miles above the planet's surface. They are positioned such that no matter where you are, at least four satellites can "see" you at any given time. These satellites send signals that travel at the speed of light until they reach your GPS device. The device then calculates how far away each satellite is based on how long it took their signals to arrive.
Once your GPS device knows how far away at least three of the satellites that are "watching" you are, it can use a process called trilateration to determine exactly where you are. To understand how trilateration works, picture three satellites in the sky above where you are standing. Now picture each satellite as having a "circle" around it that represents its scope of sight. If you know your distance from each of the three satellites, you can determine that your location is where the satellites' circles intersect. Of course, if there are more than three satellites that are "watching" you, your GPS will give you a more accurate location.
Developed for Military Use
The technology behind the GPS was originally developed by the U.S. government. The first satellite was launched in 1978, and by 1995 all of the current 24 satellites were up and operating. It cost an estimated $10 billion to build this system and $400 million per year to maintain it. The solar-powered satellites are built to last 10 years before needing replacement.
While originally intended for military use, today anyone with a GPS device can receive the satellites' radio signals. In 2000, the system was opened to the entire world because President Bill Clinton believed that it would be more useful in that capacity. And he was correct; to many people throughout the world, it's hard to imagine life without it.
Answers
GPT-4o mini
GPS works by utilizing a network of 24 satellites in orbit around the Earth, which send signals to GPS devices. By calculating the time it takes for these signals to reach the device from at least three satellites, the device can determine its exact location through a process called trilateration, where the distances create intersecting points that pinpoint the user's position. This technology, initially developed for military use, has become integral to everyday navigation for both individuals and applications worldwide.