SATELLITE
History changed on October 4, 1957, when the Soviet Union successfully
launched Sputnik I. The world's first artificial satellite was about the size of a
basketball, weighed only 183 pounds, and took about 98 minutes to orbit the
Earth on its elliptical path. That launch ushered in new political, military,
technological, and scientific developments. While the Sputnik launch was a single
event, it marked the start of the space age and the U.S.-U.S.S.R space race.
Explorer 1 became America's first satellite on January 31, 1958. Following the
Soviet success with Sputnik and the embarrassing failure in December 1957 of
the first American attempt to launch a satellite, the U.S. Army launched a
scientific satellite using a rocket that had been developed to test guided missile
components.
Explorer 1 carried an instrument package developed by a team at the State
University of Iowa under the direction of Professor James A. Van Allen. Data
returned by Explorer 1 and Explorer 3 (launched in March 1958) provided
evidence that the Earth is surrounded by intense bands of radiation, now called
the Van Allen radiation belts. This was the first major scientific discovery of the
space age
Transferred from the Jet Propulsion Laboratory and the National Aeronautics and
Space Administration.
Astronaut
The first person to travel in space, making one orbit on
April 12, 1961, was Soviet cosmonaut Yuri Gagarin,
followed in August by another cosmonaut Gherman S. Titov,
who spent 17 orbits in space. Also in 1961, American
astronauts Alan B. Shepard Jr. and Virgil I. Grissom
achieved suborbital flights to altitudes above 160 kilometers
(100 miles). Nevertheless, with this flight John Glenn became
a national hero, and Americans gained confidence that they
could compete successfully in space with the Soviet Union.
COLUMBIA
The Apollo 11 Command Module "Columbia" carried astronauts Neil
Armstrong, Edwin "Buzz" Aldrin, and Michael Collins on their historic voyage
to the Moon and back on July 16-24, 1969. This mission culminated in the first
human steps on another world.
The Apollo 11 spacecraft had three parts: the Command Module, the Service
Module, and the Lunar Module "Eagle". While astronauts Armstrong and
Aldrin descended to the Moon in "Eagle", Michael Collins remained alone in
"Columbia". For 28 hours he served as a communications link and
photographed the lunar surface. After reclaiming Armstrong and Aldrin from
the ascent stage of the Lunar Module, "Columbia" was the only part of the
spacecraft to return to Earth.
Some satellites
The highly complex new amateur radio satellite AO-40 was launched November
16, 2000, aboard an Ariane 5 rocket from Kourou, French Guiana. It is designed
to serve at least ten years as an educational aid enabling students around the
world to familiarize themselves with space techniques and communications. The
designers also hoped the satellite would allow radio amateurs to use simple and
inexpensive equipment to establish communications networks covering a large
portion of the Earth for long periods of time.
INSAT 3B
INSAT-3B is the first of the five satellites was successfully launched
under the INSAT-3 series. INSAT-3B carried 12 extended C-band
transponders, three Ku-band transponders and S-band mobile
satellite service payloads. The satellite is primarily intended for
business communication, developmental communication and mobile
communication
Types OF SATEELITE
An astronomy satellite is basically a really big telescope floating in space.
Because it is in orbit above the Earth, the satellite's vision is not clouded by the
gases that make up the Earth's atmosphere, and its infrared imaging equipment
is not confused by the heat of the Earth. Astronomy satellites, therefore, can
"see" into space up to ten times better than a telescope of similar strength on
Earth. Can you guess what kinds of things an astronomy satellite would be
looking at?These are some pictures taken by the astronomy satellite Hubble of
stellar phenomena like supernovas, distant galaxies, black holes, and quasars:
Atmospheric studies satellites were some of the very first satellites
launched into space. They generally have pretty low Earth orbits so that they can
study the Earth's atmosphere.
Alouette, the first satellite launched by Canada, was also the world's first
atmospheric studies satellite. The purpose of Alouette was to study the Earth's
ionosphere (a charged layer of the atmosphere). Canadian scientists were trying
to learn more about the aurora borealis, or northern lights - disturbances of the
ionosphere in the atmosphere which create brilliant lights in the northern skies
at night, but disturb radio communications.
It is difficult to go through a day without using a communications satellite at
least once. Do you know when you used a communications satellite today? Did
you watch T.V.? Did you make a long distance phone call, use a cellular phone, a
fax machine, a pager, or even listen to the radio? Well, if you did, you probably
used a communications satellite, either directly or indirectly.
Communications satellites allow radio, television, and telephone transmissions to
be sent live anywhere in the world. Before satellites, transmissions were difficult
or impossible at long distances. The signals, which travel in straight lines, could
not bend around the round Earth to reach a destination far away. Because
satellites are in orbit, the signals can be sent instantaneously into space and then
redirected to another satellite or directly to their destination.
USES OF SATELLIETS
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Radiation measurements from the earth's surface and
atmosphere give information on amounts of heat and energy
being released from the Earth and the Earth's atmosphere.
People who fish for a living can find out valuable information
about the temperature of the sea from measurements that
satellites make.
Satellites monitor the amount of snow in winter, the movement
of ice fields in the Arctic and Antarctic, and the depth of the
ocean.
Infrared sensors on satellites examine crop conditions, areas of
deforestation and regions of drought.
Some satellites have a water vapour sensor that can measure
and describe how much water vapour is in different parts of
the atmosphere.
Satellites can detect volcanic eruptions and the motion of ash
clouds.
During the winter, satellites monitor freezing air as it moves
south towards Florida and Texas, allowing weather forecasters
to warn growers of upcoming low temperatures.
Satellites receive environmental information from remote data
collection platforms on the surface of the Earth. These include
transmitters floating in the water called buoys, gauges of river
levels and conditions, automatic weather stations, stations that
measure earthquake and tidal wave conditions, and ships. This
information, sent to the satellite from the ground, is then
relayed from the satellite to a central receiving station back on
Earth