Book 3, Question 89 · Video
Why Does GPS Know Where You Are?
Radio beeps take time to travel. So the farther a satellite is, the later its beep arrives. Comparing those delays pins you on the map!
Read the full answer →What Crafty Clover says in this video
Intro
Hey there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why does GPS know where you are?
The Big Idea
GPS is a team of clocks in space. Your phone listens to several satellites and figures out how far away each one is. Radio beeps take time to travel. So the farther a satellite is, the later its beep arrives. Comparing those delays pins you on the map! Four satellites are enough to lock in your spot in 3-D, even how high you are.
Satellites Beacon
Step one: the satellites beacon. Each satellite shouts its name and the exact time. Many of them circle Earth, all sending these signals.
Phone Listens
Step two: your phone listens. Your device catches several of those beacons. A later beep means a longer trip through space, so a farther satellite!
Dot Appears
Step three: a dot appears. Picture a circle around each satellite. With three or four satellites, the circles all meet at one spot, and that spot is you. The map drops a pin right there!
A Closer Look
Let's take a closer look at GPS! Your phone listens. Several satellites in space send their signals. The signals reach Earth, and the pin shows where you are!
Quick Facts
Quick facts! GPS stands for Global Positioning System. Other countries have similar satellite networks. Tall buildings can bounce the signals and make the pin jump. Airplane mode can turn GPS listening off to save battery. And hikers, airplanes, and farm tractors all use the same sky clocks!
Think Like a Scientist
Now, think like a scientist! Play the GPS game. Have three friends each hold a string tied to the same toy. Each friend stands far away from the others. Where all the strings pull tight is like a GPS fix. Can you find the toy from the strings alone?
Outro
GPS shows us that clocks in space and a little math can find you anywhere. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!