GPS helps your phone, watch, or car figure out exactly where you are on Earth. GPS stands for Global Positioning System.
Satellites in space. Many GPS satellites orbit Earth high in space. They circle the planet, so there are always some up above you.
Signals travel down. Each satellite sends out signals that include the time the signal was sent. These signals travel down to Earth at the speed of light.
Your device listens. Your phone, watch, or car listens for signals from several satellites. It figures out how long each signal took to arrive. Hearing more than one satellite helps it find the right spot.
Finding the spot. By knowing how long it took each signal to arrive, your device calculates how far away each satellite is. The spot that fits all those distances is where you are!
Think of it like friends calling out how far away you are. Each friend tells you how far you are from them. When you put all the clues together, you can figure out exactly where you stand.
Remember: GPS uses satellites in space, the satellites send signals, your device listens to several of them, and together they find your spot. Science helps us explore!
What to remember
- GPS uses satellites high up in space.
- Satellites send signals down to your device.
- Your device listens to several signals to find the spot.
- GPS helps with maps, directions, and finding places.
Words to know
- GPS
- Global Positioning System, which helps find where you are.
- Satellite
- A helper in space that circles the Earth.
- Signal
- A message sent from a satellite to your device.
- Location
- The exact place where something is.
For grown-ups
GPS is a satellite navigation system. A receiver listens to precisely timed signals from multiple satellites and works out its position by comparing how long each signal took to arrive (trilateration); four or more satellites give an accurate 3D fix. It needs a reasonably clear view of the sky and powers maps, navigation, and location features. The kid-level idea: many space helpers plus careful timing equals knowing where you are.
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