Uses of satellites

(i) Satellite communication
Communication satellites are used to send radio, television and
telephone signals over long distances. These satellites are fitted with
devices which can receive signals from an Earth – station and transmit
them in different directions.
(ii) Weather monitoring
Weather satellites are used to photograph clouds from space and
measure the amount of heat reradiated from the Earth. With this
information scientists can make better forecasts about weather. Youmight have seen the aerial picture of our country taken by the satellites,
which is shown daily in the news bulletin on the television and in the
news papers.
(iii) Remote sensing
Collecting of information about an object without physical contact
with the object is known as remote sensing. Data collected by the
remote sensing satellities can be used in agriculture, forestry, drought
assessment, estimation of crop yields, detection of potential fishing zones,
mapping and surveying.
(iv) Navigation satellites
These satellites help navigators to guide their ships or planes in
all kinds of weather.

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