Observing the Earth
using Technology
COS 10 Bullet 1
Describe technology used to investigate Earth.
(Examples: sonar, radar, seismograph, weather
balloons.)
The History of Observing Objects
from Afar
Navigators began experimenting with ways to observe
the stars and planets during
the nineteenth century.
One example to obtain long-range
photographs was to attach a camera to a
pigeon.
During the American Civil War, balloons
were lifted during battles to see the
placement of enemy troops.
During the First World War, unarmed
observation planes would take off with a
camera strapped to the undercarriage.
As technology progressed, it became
possible to use Sonar, Radar, the
seismograph, and orbiting satellites.
SONAR
SONAR is an acronym for SOund
NAvigation and R anging.
SONAR — is a technique that
uses sounds under water to
navigate, communicate or to
detect other vessels.
Exploration
by SONAR
Sonar image of the USS Monitor on the ocean floor.
Shipping lanes on the nation's waterways
are continually shifting. Surveyors create
maps of the bottom of rivers, lakes, and
oceans using Sonar. No matter the method
used, the resulting maps are used to aid in
maritime navigation, scientific research,
sports, and mineral exploration.
Surveyors observe the ocean’s floor for
volcanoes and other features that stick up
above the surrounding seafloor.
http://www.punaridge.org/doc/factoids/DigitalData/Default.htm
RADAR is an acronym that stands
for RAdio Detection And Ranging.
Radar
is
a
system
that
uses
electromagnetic waves to identify the range,
altitude, direction, or speed of both moving
and fixed objects such as air craft, ships,
motor vehicles, weather formations, and
terrain.
A transmitter emits radio waves, which are
reflected by the target and detected by a
receiver, typically in the same location as
the transmitter.
A weather Radar consists of a parabolic
dish (it looks like a satellite dish) encased in
a protective dome and mounted on a tower
of up to five stories tall.
Exploration
by Radar
Example of a Radar image
A meteorologist uses images that are received by
Radar to give information about the weather.
When looking at a weather map, a meteorologist
needs to know where the cold air is, where the
warm air is, where it is raining, what type of
clouds are in the area, and many more things..
Forecasts need to be timely and accurate and
radars give meteorologists detailed information
very quickly.
This is a location map for the Radar sites.
Earthquakes generate seismic waves which
can be detected with a sensitive instrument
called a seismograph.
http://www.thetech.org/exhibits/online/quakes/seismo/
http://en.wikipedia.org/wiki/Seismograph
This is a Strong Motion seismometer that
measures acceleration. This model is a K2
made by Kinemetrics and part of the Pacific
Northwest Seismograph Network.
http://www.answers.com/topic/kinemetrics-seismograph-jpg
Seismometers measure and record the size
and force of seismic waves. By studying
seismic waves, geologists can map the
interior of the Earth, and measure and
locate earthquakes and other ground
motions.
http://cse.ssl.berkeley.edu/lessons/indiv/davis/hs/Seismograph.html
Ever since people first became curious about
earthquakes, they have tried to design some
kind of seismograph. This seismograph can
be built will some simple materials.
A weather or sounding balloon is a
balloon which carries instruments aloft to
send back information on atmospheric
pressure, temperature, and humidity by
means of a small, expendable measuring
device called a radiosonde.
Close up of a hydrogen filled
balloon at Cambridge Bay
Upper Air station, Nunavut,
Canada
http://en.wikipedia.org/wiki/Weather_balloon
Twice a day, every day of
the
year,
weather
balloons are released
simultaneously
from
almost 900 locations
worldwide!
This includes 92 released
by the National Weather
Service in the US and its
territories.
As the balloon climbs it encounters lower air
pressure which causes it to expand to many
times its original size. Eventually the balloon
bursts and the radiosonde falls back to the
surface.
The Balloon-Borne
Sounding System or
BBSS
A radiosonde measures various
atmospheric
parameters
and
transmits them to a fixed receiver.
The radiosonde that
falls back to the
Earth’s surface.
As technology progressed, it became
possible to use orbiting satellites.
The United States
launched its first
weather satellite,
TIROS 1, in 1960.
http://space.skyrocket.de/index_frame.htm?http://www.skyrocket.de/space/doc_sdat/tiros.htm
http://noaasis.noaa.gov/NOAASIS/ml/genlsatl.html
GOES (Geostationary Orbiting Environmental
Satellite) orbit the earth at the same rate that
the earth rotates. It always sees the same
area of the earth and stays at the same point
over the equator.
POES (polar orbiting environmental
satellite) scans the earth from north to
south. As the earth rotates on its axis,
the satellite is able to scan an area
farther to the west with each pass.
http://noaasis.noaa.gov/NOAASIS/ml/genlsatl.html
www.newscientist.com/.../dn9311/dn9311-1_600.jpg
www.primidi.com/images/cosmic_satellites.jpg
Scientists use the information that they
acquire from Space for geology studies,
agriculture studies, meteorology, etc.
The moon is Earth’s
satellite. Observing the
accomplished by using
instruments ranging from
to large telescopes.
Moon as seen with
the naked eye
only natural
moon can be
a variety of
the naked eye
Moon as seen with a
pair of binoculars
Moon as seen through a
telescope
http://www.netaxs.com/~mhmyers/moon.tn.html
http://en.wikipedia.org/wiki/Observing_the_Moon
http://www.etsu.edu/physics/etsuobs/starprty/21200mwc/moontour.html