What is remote sensing? How are satellites useful in remote sensing?

Remote sensing is a method by which of we obtain information about an object or phenomenon without making physical contact with the object.

Since the artificial satellite is the main source of transmission of information. The modern satellite contains a high-resolution camera, many sensors, transponders (a device for receiving and transmitting radio signal). These cameras collect remotely sensed images of the Earth and that image is sent to the base station. Using satellite we carry out a geological survey of metallic ores present in the earth crust, water resource, agriculture etc. It is also used in oceanography and study the movement of fishes.

Additional Information:

They are two types of remote sensing:-

a) Active Remote sensing: the signal is emitted by a satellite and its reflection by the object is detected by the sensor.

b) Passive Remote sensing: when the reflection of sunlight is detected by the sensor.