The following are the fields where satellites are being used:
(i) remote sensing, (ii) spying, (iii) Communication, (iv) Weather forecasting.
(i) In remote sensing, infrared photography is used from a high altitude. The technique has improved a lot and the resolution has gone down to about 5 m2 in area. This technique has helped in mineral and oil exploration. It has also helped in the study of living beings and crop pattern.
(ii) In the field of communication, satellites have brought revolution during last 20 years.
Now net items are flashed all around the globes. Cricket matches can be watched anywhere on the globe which are played in one small part of a country. Internet, e-mail etc. have brought people much more closer and world has become a unified entity.
(iii) In spying also, we use IR technology.
(iv) Weather forecasting has become more reliable with the use of satellite. The rains, cyclones can now be predicted with greater accuracy 36 hours in advance or even earlier. Movement of glaciers, position of ice and snow deposition and resulting flow of water in rivers is knowing well in advance.
