A constellation of satellites constantly hovers over us to help guide us
You are walking down the street and, suddenly, you realize that you do not know how to get to your destination. Not to worry: finding your way around is as easy as unlocking the mobile, entering the map app, entering the address and follow the directions.
But, have you ever wondered how can your phone constantly know where you are, even when you are moving? Although we do not usually think about it, every time we use GPS a technological miracle takes place right in our hands.
The GPS is a method that allows to determine the position of an object on Earth with great precision (the margin of error is just a few meters), 24 hours a day and regardless of weather conditions.
Its letters name stand for Global Positioning System. It is used in cell phones, but there are also devices for cars or for day trips to the mountain, among many other apps.
GPS are able to know where we are thanks to a fleet of about thirty satellites that orbit constantly around our planet. They fly over the Earth about 20,200 kilometers away and emit signals that tell their position.
This small constellation of satellites follows a perfect choreography so that no point on the planet remains uncovered. In fact, from every place in the world, at least four of them are received.
When we ask our GPS to tell us where we are, it takes the signal from the available satellites. It then calculates the distance between each one of them and that’s how it obtains exact data on our location.
As you can see, every time we use our GPS a small technical miracle happens. One that takes the information from different satellites high up right back down into our hands.
Can you even imagine how hard it must have been in the past to find your way around without these devices?