Download - GPS Basics

1. In which direction do latitude lines run

on the globe?

1. In which direction do latitude lines run

on the globe? • A. East/West

• B. North/South

• A. East/West

• B. North/South

2. In which direction do longitude lines run on a globe?

2. In which direction do longitude lines run on a globe?

• A. East/West

• B. North/South

• A. East/West

• B. North/South

3. What does GPS mean?

3. What does GPS mean?

• A. Globe Pole System

• B. Global Positioning System

• C. Ground Placement System

• A. Globe Pole System

• B. Global Positioning System

• C. Ground Placement System

4. Who uses GPS?4. Who uses GPS?• A. U.S. Army

• B. Football Coaches

• C. Scientists

• D. All of the above

• A. U.S. Army

• B. Football Coaches

• C. Scientists

• D. All of the above

5. Where does a GPS find its information?

5. Where does a GPS find its information?

• A. The Internet• B. Washington D.C.• C. Satellites• D. All of the above

• A. The Internet• B. Washington D.C.• C. Satellites• D. All of the above

LatitudeLatitude LongitudeLongitude

• A way to describe our location on the earth

• Tells how far north/south and east/west

• These are called coordinates

• A way to describe our location on the earth

• Tells how far north/south and east/west

• These are called coordinates

Latitude/LongitudeLatitude/Longitude

NN

EEWW

SS

Latitude LinesLatitude Lines

The lines run east and west, but they measure degrees north or south of the equator.The lines run east and west, but they measure degrees north or south of the equator.

Equator – 0oEquator – 0o

Longitude Lines…Longitude Lines…

…run north and south. Where do all the lines meet?…run north and south. Where do all the lines meet?

Instead of measuring from the equator, longitude is measured from the prime meridian, a line running through Greenwich, England.

Instead of measuring from the equator, longitude is measured from the prime meridian, a line running through Greenwich, England.

Prime Meridian – 0oPrime Meridian – 0o

By combining latitude and longitudeBy combining latitude and longitude

We can pinpoint any location on Earth.We can pinpoint any location on Earth.

We measure latitude and longitude in degrees.We measure latitude and longitude in degrees.

There are 360 degrees in a circle.

One degree is 1/360th the way around the earth.

There are 360 degrees in a circle.

One degree is 1/360th the way around the earth.

We identify points on the Earth by specifying how many degrees North or South (of the equator)

We identify points on the Earth by specifying how many degrees North or South (of the equator)

And how many degrees East or West (of the prime meridian) the points are located.

And how many degrees East or West (of the prime meridian) the points are located.

Global Positioning SystemGlobal Positioning System

GPS is used by millions of people around the world everyday.One of the earliest uses of the GPS was by the military branches. The soldier on the left is using a GPS to map a location for troops to land on a beach. Other uses by the military include tracking soldiers, vehicles, and supplies.

http://images.google.com/imgres?imgurl=http://www.defenselink.mil/photos/Jan2000/000103-N-5448C-004.jpg&imgrefurl=http://www.defenselink.mil/photos/Jan2000/000103-N-5448C-004.html&h=1275&w=1785&sz=314&hl=en&start=13&tbnid=xxGvz7mSAN7SkM:&tbnh=107&tbnw=150&prev=/images?q=uses+of+gps&svnum=10&hl=en&rls=GGIC,GGIC:2007-03,GGIC:en&sa=N

GPS is used to help locate people who have On-Star in their vehicles. On-Star is a safety and security system in cars and trucks created to connect drivers to emergency assistance and hands-free calling. Portable GPS systems are placed in vehicles to help people find their way to a destination.

GPS is used in boats to help in case of emergencies such as storms or engine failures.

GeoCACHING is a new sport that uses GPS to find hidden items or messages left by members of GeoCACHING clubs. People can look for these items if they know the latitude and longitude of the items.

This man is using a GPS to conduct water-typing surveys on Washington state’s Lopez and Orcas Islands. The surveys are being conducted on certain streams to determine the distribution of fish and fish habitat, and to ensure that the Island's trout and salmon streams are mapped correctly so they can receive appropriate legal protection.

This man is using a GPS to conduct water-typing surveys on Washington state’s Lopez and Orcas Islands. The surveys are being conducted on certain streams to determine the distribution of fish and fish habitat, and to ensure that the Island's trout and salmon streams are mapped correctly so they can receive appropriate legal protection.

How does the GPS help people in all

these different situations?

How does the GPS help people in all

these different situations?

How GPS

(Global Positioning System)

Works:

How GPS

(Global Positioning System)

Works:

Credit: http://nasaexplores.com

• Imagine you are somewhere in your town. You are TOTALLY lost. You ask someone, “Where am I?” They say, “You are 5 miles from the fire station.”

• This is nice, but it really doesn’t help you. You could be anywhere on a circle 5 miles around the fire station!

• Imagine you are somewhere in your town. You are TOTALLY lost. You ask someone, “Where am I?” They say, “You are 5 miles from the fire station.”

• This is nice, but it really doesn’t help you. You could be anywhere on a circle 5 miles around the fire station!

5 miles

• You ask someone else where you are. They say, “You are 7 miles from the library.” If you combine this information with the fire station information, you have two circles that cross.

• You now know that you must be at

one of these two points, if you are 5 miles from the fire station and 7 miles from the library.

• You ask someone else where you are. They say, “You are 7 miles from the library.” If you combine this information with the fire station information, you have two circles that cross.

• You now know that you must be at

one of these two points, if you are 5 miles from the fire station and 7 miles from the library.

• A third person tells you that you are 4 miles from home.

• This circle will only cross the other circles at one point.

• You know exactly where you are. The only place all these circles cross is at the school!

• A third person tells you that you are 4 miles from home.

• This circle will only cross the other circles at one point.

• You know exactly where you are. The only place all these circles cross is at the school!

• GPS satellites work to the same way to find the location of a plane, ship, car, or a person lost in the city.

• GPS satellites work to the same way to find the location of a plane, ship, car, or a person lost in the city.

• There are 24 GPS satellites orbiting Earth right now.

• The more of them that your GPS can lock onto the more accurately your position can be determined.

• There are 24 GPS satellites orbiting Earth right now.

• The more of them that your GPS can lock onto the more accurately your position can be determined.

NASA/JPL

This illustration shows how the GPS receiver can see the satellites as they pass overhead.

This illustration shows how the GPS receiver can see the satellites as they pass overhead.

NASA/JPL

• By collecting the information from several satellites, a GPS unit can determine its exact location on Earth.

• By collecting the information from several satellites, a GPS unit can determine its exact location on Earth.

http://www.pbs.org/wgbh/nova/shackletonexped/navigate/gps/gps02.html

“Doing the Math” with GPS“Doing the Math” with GPS

http://www.pbs.org/wgbh/nova/shackletonexped/navigate/gps/gps13b.html


You are here…

…not up here!

You’ve discovered that you are in Montgomery, Alabama! Your GPS receiver figures all this out in less than a second. The GPS works by knowing the time of both the satellite and the GPS receiver.

Garmin GPS 72Garmin GPS 72

PowerPower PagePage

QuitQuit(Works like “Esc” or “Back”)(Works like “Esc” or “Back”)

LongitudeLongitude

LatitudeLatitude

ElevationElevation SatellitesSatellites

What to look for and recordWhat to look for and record

GPS SimulatorGPS Simulator

• Turn the GPS on with the Red button• Press the Page Button twice• Press the Menu Button once• Start Simulator Press Enter• This is a simulator showing what the

screen should look like. When we go outside, we do not want to be on simulator. We want to be on the screen acquiring satellites.

• Turn the GPS on with the Red button• Press the Page Button twice• Press the Menu Button once• Start Simulator Press Enter• This is a simulator showing what the

screen should look like. When we go outside, we do not want to be on simulator. We want to be on the screen acquiring satellites.

Let’s go exploring!Let’s go

exploring!

For Help:For Help:

Jerry Cobbs

AMSTI-GLOBE

Technology Specialist

[email protected]

Jerry Cobbs

AMSTI-GLOBE

Technology Specialist

[email protected]

Lynn Vaughan

AMSTI-GLOBE

Resource Specialist

[email protected]

Robin Nelson

AMSTI-GLOBE

Administrator

[email protected]

AMSTI-GLOBE

www.amsti.org/globe

The GLOBE Program

www.globe.gov

PowerPoint designed by Polly Crow, Martha Anne Allison, Jerry Cobbs, Lynn Vaughan, Sue McDaniel

Judy ReevesAMSTI-GLOBE Resource [email protected]