What is remote sensing?

Remote sensing is a new technology developed on the basis of aerial photography, which was developed in the early 1960s. Started for aerial remote sensing, since 1972, the United States launched the first land satellite, marking the beginning of the era of space remote sensing. After decades of development, remote sensing technology has been widely used in resources and environment, hydrology, meteorology, geology and geography and other fields, and has become a practical and advanced space exploration technology.

Remote sensing uses remote sensors to detect the characteristics of ground objects from the air. According to the principle that different objects have different responses to the spectrum, it is of great significance to recognize various ground objects on the ground. That is to say, remote sensors on flying objects such as airplanes, spaceships and satellites above the ground are used to collect ground data and obtain information from them, and ground objects can be identified through recording, transmission, analysis and interpretation.

What is remote sensing?

In fact, Baidu Encyclopedia explains it very clearly, just like the previous one said. In fact, it is simple photography, and there are different images on different platforms with different resolutions. Usually, cameras can capture what we can see, but satellite sensors can capture what we can't see, such as infrared rays. RS can let us see the world from another angle. Some things are indistinguishable from visible light, but they can be seen from other spectra. Remote sensing also provides us with macro monitoring. For example, I can use large-scale images to analyze the world's vegetation industrialization, which is impossible except remote sensing, a large-scale and high-time resolution medium.

Photogrammetry should extract information from remote sensing images and provide basis for GIS analysis. I don't know much about this.

What is a remote sensing picture?

Remote sensing is to detect the characteristics of ground targets from different angles and heights. From the target, it can be divided into land resources remote sensing, ocean remote sensing and meteorological remote sensing, including ground, ocean and atmosphere, which are mainly used for ground observation. From the height, there are aerial remote sensing and satellite remote sensing. The height of aerial remote sensing is generally between 3000 meters and 5000 meters, and satellite remote sensing is generally between 500 kilometers and 900 kilometers. According to the physical band of remote sensing, it can be divided into visible light remote sensing, infrared remote sensing and microwave remote sensing. The main characteristics of remote sensing are wide coverage, fast frequency and large amount of information. For example, observing things with the naked eye is generally carried out from four directions, while remote sensing is different. Now it can observe an object from more than 200 angles. To use an image point metaphor, visible light remote sensing, which is widely used now, is like a camera with very high sensitivity and precision and very large coverage.

The image obtained by remote sensing is a remote sensing image.