How Do Satellites “TAKE PICTURES” of the Earth 🌍

When it comes to taking pictures, we naturally think of cameras and shutters.It is common to think about pointing the camera at what needs to be captured, and as soon as the shutter is pressed, you can get an image. This image will contain data with the three primary colours on 2D pixels. However, the case is quite different when it comes to observation of the earth (surface / atmosphere).The specific imaging principle via satellites is slightly more complex. Satellite's can be divided into geostationary and polar-orbiting. This division is according to their orbits. We know that the angular velocity of the earth’s rotation is fixed. If a satellite is used to monitor the earth constantly, then the height of the satellite’s orbit is fixed. This is a fixed satellite. The height of the fixed satellite is 36,000 km, and the radius of the earth is about 6,371km. It is conceivable that the angle of view of the earth from the satellite is only 18°. How can the effect of direct imaging be