GPS and Navigation
Subject Topics:
Geography, Geometry and Trigonometry
GPS and Navigation
1. What do you know about GPS?
2. Have you used a GPS? How?
3. What does GPS stand for?
4. How do you think GPS works? What is
involved?
Early Greek Contributions to Navigation
GPS and Navigation
5. How have humans navigated
their world, in the past, and in
the present?
There’s a lot that goes into GPS. Here are
some of the organizations involved:
Click on each symbol or banner to go to their websites to learn more.
The home of the
discovery of GPS and
research operations for
the Navy.
Department of Defense
The Nat. Geodetic Survey is responsible for maintaining
the National Spatial Reference System and the
Continuously Operating Reference Station network.
US Naval Observatory
What is a CORS?
Continuously Operating Reference Station (CORS)
A permanent Global Navigation Satellite System (GNSS) receiver,
antenna (with a surveyed reference position), and support equipment
The US Geodetic Survey Runs the Continuously Operating
Reference Station (CORS) network across N. America.
Our Nearest
Stations Are:
Can you find your
nearest CORS
Location?
Click Here to Find
Them.
Satellites
GPS works because of Satellites!!
A Satellite is an artificial object that has been
put into orbit
Used for a large number of purposes:
• Earth Observation
• Communication
• Weather
• research
What Satellites are Overhead Right Now?
Click the satellite picture to find out.
How Do Satellites and GPS units
communicate?
•31 satellites
•Radio Waves (mechanical
waves)
•Atomic clocks and accurate
time
•Geodesy (the science of
accuratly measuring and
understanding the earth’s
geometric shape, orientation in
space, and gravity field)
•Mathematical equations
How long does it take a radio signal from a
satellites to reach your GPS unit?
Distance (D)= time it takes the satellite radio wave to travel (T)
x Speed of light (300 km/ms)
or D=T x (300/ km/ms)
GPS and Navigation
How does it work?
Watch the following video. Your teacher will stop it
for you every minute. Take notes about what you
see. Be sure to include:
Question 6
• How does a GPS work?
• What are satellites?
• How many are there?
GPS and Navigation
How does it work?
Watch the following video. Your teacher will stop it
for you every minute. Take notes about what you
see. Be sure to include:
Question 7
•What’s the big event happening?
•Tell 3 ways this will help you.
• 2 new facts you learned about GPS
Trilateration
Now that
you’ve
watched a
few videos…
8. Explain
what is
Trilateration?
Trilateration
90° latitude (+)
Longitude and Latitude
0° latitude
90° latitude ()
http://oceanservice.noaa.gov/education/lessons/plot_course.html
There are 60 minutes per degree of longitude
or latitude, written as ('), and there are 60
seconds per minute (").
If you were looking at the top of the Earth, from
the North Pole, much like looking down at the
face of a clock, fill in the degrees of longitude on
the diagram below starting with the prime
meridian (0°) at 6 o’clock.
• 9. What is an additional question you have
about GPS after watching the quick videos?
• 10. List 4 ways you or anyone could use a
GPS.
• 11. Why would the US Military create the GPS
system?
GIS
A geographic information system (GIS) is a
computer system for capturing, storing,
checking, and displaying data related to
positions on Earth’s surface.
GIS can show many different kinds of data on
one map.
This enables people to more easily see, analyze,
and understand patterns and relationship
GIS: What is it? How
does it work?
Watch the following video. Your teacher will stop it
for you every minute. Take notes about what you
see. Be sure to include:
• 12. What does GIS stand for?
• 13. How is it used?
• 14. 2 more new facts
http://www.youtube.com/watch?v=-ZFmAAHBfOU
Cartographer
Cartographer
14. What is a cartographer?
15. Give 3 examples of what a Cartographer does.
16. Would you want to be a cartographer? Why
or why not?
911 Service & GIS
http://m.urgentcomm.com/ng-911/gis-willbecome-hero-911-says-apco-panelist
How is GIS being used to help 911 service?