GPS

1
GPS
2
1. In which direction do latitude lines run on
the globe?

• A. East/West
• B. North/South

3
2. In which direction do longitude lines run on a
globe?

• A. East/West
• B. North/South

4
3. What does GPS mean?

• A. Globe Pole System
• B. Global Positioning System
• C. Ground Placement System

5
4. Who uses GPS?

• A. U.S. Army
• B. Football Coaches
• C. Scientists
• D. All of the above

6
5. Where does a GPS find its information?

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

7
Latitude
Longitude
8
Latitude/Longitude

• A way to describe our location on the earth
• Tells how far north/south and east/west
• These are called coordinates

N
E
W
S
9
Latitude Lines
Equator 0o
The lines run east and west, but they measure
degrees north or south of the equator.
10
Longitude Lines
Instead of measuring from the equator, longitude
is measured from the prime meridian, a line
running through Greenwich, England.
Prime Meridian 0o
run north and south. Where do all the lines
meet?
11
By combining latitude and longitude
We can pinpoint any location on Earth.
12
We measure latitude and longitude in degrees.
There are 360 degrees in a circle. One degree
is 1/360th the way around the earth.
13
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.
14
GPS
Global Positioning System
15
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.
16
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.
17
GPS is used in boats to help in case of
emergencies such as storms or engine failures.
18
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.
19
This man is using a GPS to conduct water-typing
surveys on Washington states 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.
20
How does the GPS help people in all these
different situations?
21
How GPS (Global Positioning System) Works
Credit http//nasaexplores.com
22

• 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 doesnt help you. You
  could be anywhere on a circle 5 miles around the
  fire station!

23

• 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.

24

• 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!

25

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

26

• 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.

27
This illustration shows how the GPS receiver can
see the satellites as they pass overhead.
NASA/JPL
28

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

29
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps02.html
30
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps03.html
31
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps04.html
32
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps05.html
33
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps06.html
34
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps07.html
35
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps08.html
36
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps09.html
37
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps10.html
38
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps11.html
39
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps12.html
40
Doing the Math with GPS
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps13.html
41
Doing the Math with GPS
You are here
not up here!
http//www.pbs.org/wgbh/nova/shackletonexped/navig
ate/gps/gps13b.html
42
Youve 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.
43
Garmin GPS 72
Power
Page
Quit
(Works like Esc or Back)
44
What to look for and record
45
GPS 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 are 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.

46
Lets go exploring!
47
For Help

• Jerry Cobbs
• AMSTI-GLOBE
• Technology Specialist
• jerry_at_amsti.org

Lynn Vaughan AMSTI-GLOBE Resource
Specialist lynn_at_amsti.org
Robin Nelson AMSTI SDE Science Coordinator robin_at_a
msti.org
Judy Reeves AMSTI-GLOBE SDE Specialist judy_at_amsti
.org
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