Stages in remote sensing
Also called: Remote sensing process · Topic: Remote Sensing, GIS and GNSS · NCERT: Class 11, Ch 6 "Introduction to Remote Sensing"
Meaning
The stages in remote sensing are the eight steps that turn energy from an object into a usable map. First, a source gives out energy. This is usually the sun, but it can be the sensor itself. The energy travels to the earth's surface and interacts with it. The reflected or emitted energy then travels back up through the atmosphere, and a sensor detects it. The sensor turns the energy into photographic or digital data. Information is then taken out of that data and shown as maps or tables. Knowing these steps shows where errors can creep in, such as haze in the atmosphere or faults in the sensor.
Example
Sunlight falls on wheat fields in Punjab. The healthy crop reflects strongly in near infrared, and a LISS camera on an IRS satellite records this energy. The data are sent down to the earth receiving station at Shadnagar near Hyderabad. There they are corrected and turned into a crop map.
Don't confuse with
- Sequence of GIS work: this starts after the data already exist. It runs from data input to attribute entry, editing, linking and analysis. It does not cover how a satellite collects energy.