used almost everyday by everyone. Even though you can't see it, there will
probably be one traveling above you today. Satellites are used for many things
such as communication, oceanography, astronomy, surveillance, and a variety of
other things as well . They help many scientists get a perceptive view at all
kinds of objects anywhere in the world.
Communication satellites work non-stop 24 hours a day to keep the entire
world linked together. Until recently NASA had been the only one's launching
satellites, but now many private companies are benefiting from what a satellite
can do. Once a satellite becomes geosynchronous, rotates with the earth orbit,
a satellite is ready to work. It then beams messages to a ground station, the
ground station receives these messages by using a device called a transponder.
Which interrupts the message and then distributes it. By doing this satellite
stations can than transport telephone service, data, or television
transmissions to almost anywhere. These communication satellites are used for
things like an overseas phone call or beaming 150 channels into your living
New advancements look to focus on packing more information into
frequencies, because virtually all frequency transmitters are being used. And
this would allow more and more companies to transport all types of data.
Another use for satellites is in the field of oceanography. In 1798, the
first three oceanography satellites went out ( Tirus, Nimbus 7, Seasat) and
although they didn't do much they led the way to huge discoveries (Robinson 34).
Now marine scientists and marine biologist are able to detect almost everything
that goes on in the ocean. They use satellites to detect the oceans affect on
environment, analyze wave patterns, monitor marine surface life, analyze ocean
tendencies and currents, and get a complete synoptic view of the ocean. These
things help them tell you what the water will be like, and help them find out
about ocean life.
Astronomy satellites are mostly new technology. These satellites are
mounted on earth-orbiting satellites or on deep space probes, and therefore can
give us an unobstructed view with out the earth's atmosphere interfering. These
satellites carry detectors to record electromagnetic radiation at wavelengths
shorter than visible light (McGraw-Hill 41). Many different satellite astronomy
techniques are used, one of the more prevalent ones is ultraviolet. Evolving in
the 1940's, when Lyman Spitzer pointed out that the Earth's atmosphere is
opaque to ultraviolet light. Out of ultraviolet developed solar ultraviolet ,
with a deeper space base it uses low and high spectral lines, to determine
radiation on an object throughout the solar atmosphere. X-ray satellites are
all used, it looks at x-ray emission from the sun and stars.
Lastly, an interesting satellite use is in the field of surveillance or spy
satellites. There are four kinds of major satellites (White 100). The most
commonly used one, reconnaissance use cameras to take pictures of a particular
place from up above. They also have radar and infrared detectors so they can
detect things in the dark or things that are covered by something or
camouflage. Most of Russia's reconnaissance are known as COSMOS, the U.S. first
one was called Big Bird. Ocean Surveillance satellites are used to search for
ships or submarines. They can spot nuclear vessels. And new advancements may
allow them to scan the depths of the ocean. Early warning and "Elint"
satellites are primarily used by the armed forces. These basically protect
countries from sneak attacks, and can be used to detect if other countries are
building or storing nuclear warheads. Elint is the basic spy satellite it picks
up radio transmissions, and maps location of countries defense bases. It is the
most important military satellite because it does not let another country to
put together an attack without another country knowing.
As you can see satellites are an integral part of everyday life. They have
thousands of uses and perform it without most ever being seen. Just think now
how many satellite dishes you have seen on top of a house and that's just one
aspect. Satellites are becoming more and more advanced every year and will lead
the way into the 21st century.