GPS

GPS stands for Global Positioning System. It uses satellites in space to tell you exactly where you are on Earth. Your phone, car navigation, and many other devices use GPS. It can pinpoint your location within a few feet. GPS has changed the way we travel and explore the world.

How GPS Works

There are about 30 GPS satellites orbiting Earth. Each one sends out a signal that includes the time and the satellite's position. Your GPS device receives signals from at least four satellites. By measuring how long each signal took to arrive, the device calculates your exact location on Earth.

Uses of GPS

GPS is used in many ways. It helps you get driving directions and find nearby restaurants. Hikers use GPS to avoid getting lost. Farmers use GPS to plant crops in precise rows. Scientists use GPS to track animal migrations. Emergency services use GPS to find people who call for help.

Fun Facts

• GPS was originally developed by the U.S. military and became available to everyone in the 1980s.
• GPS satellites orbit about 12,550 miles above Earth.
• GPS works in any weather and anywhere in the world, 24 hours a day.

Did You Know?

GPS must account for Einstein's theory of relativity to work correctly! Time moves slightly faster for the satellites in space than it does on Earth because of gravity. Without adjusting for this, GPS calculations would be off by about 6 miles per day. Physics is at the heart of this everyday technology!