Basic Principles of Remote Sensing

Remote sensing is the science of collecting information about the Earth from a distance, usually using satellites or aircraft — without touching the surface.

Basic Principles of Remote Sensing

Energy Source (Sun) ☀️
Everything starts with the Sun, which sends energy (light) to Earth.
Interaction with Earth 🌳🏙️💧
This energy hits the Earth's surface — like forests, water, buildings — and gets:
- Reflected
- Absorbed
- Transmitted
Sensors Detect the Energy 🛰️
Satellites or aircraft have sensors (cameras) that capture the reflected energy.
Data Transmission 📡
The sensors send the collected data back to ground stations.
Image Processing 💻
The raw data is processed into images or maps using computer software.
Analysis 🧑‍💼
Scientists or analysts study the images to find out what's happening — like land use, vegetation health, urban growth, disasters, etc.

Example:

Imagine you're taking a photo of a city from an airplane. You don't touch the ground, but your photo tells you what's there — buildings, rivers, trees. That's remote sensing.

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Photogrammetry

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Logical Data Model in GIS

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