Satellite remote sensing is all about interpreting and establishing the relations between naturally-occurring elements and the measurements of electromagnetic energy reflected or emitted from the surface of the Earth or the atmosphere. These measurements constitute many locations from the Earth’s surface via satellites resulting in satellite camera imagery for further research.
It has been more than 50 years since the first satellite was launched for remote sensing and Earth observation; during this period, the satellite cameras have evolved from small-scale production of low-resolution images to providing terabytes of information daily. Today, these satellite cameras are mostly used for Earth observation.
As of now, more than 5000 satellites are orbiting the Earth, some of them equipped with cameras that measure different sections of the microwave, infrared, and visible regions of the electromagnetic spectrum. Most of these devices use passive sensor technology; it means that they measure the emitted thermal energy or the reflected solar radiation from the Earth’s atmosphere or surface.
Today, newer devices use active sensor technology, which emits energy and record the backscattered or reflected response; this data helps find various types of information about our planet.
What Is Earth Observation?
Before we dive into how satellite cameras changed, let’s learn about the basics first. Earth observation is all about collecting information about the Earth with the help of remote sensing and satellite cameras. The main advantage of using these tools is that you will obtain data otherwise not possible to collect.
How Did Earth Observation Start?
Based on research, it has been found that Earth observation started almost immediately after the invention of photography. Nadar (or Gaspard-Felix Tournachon) was the first to capture an aerial photograph from a hot air balloon. After realizing the potential of these pictures, he started offering his services to the French military. Similarly, Arthur Batut started using kites for the same purpose. He attached timed cameras to the kites and produced amazing aerial photographs.
However, with the invention of the airplane, Earth observation photography was taken to another level. The next breakthrough came in the form of the V-2, the world’s first space rocket, which was used as a weapon by Germans. When the Second World War ended, the V-2 technology was acquired by the Americans. It was launched in 1946 to capture the first image of the Earth from space.
Space Age Today
In today’s time, the revolution of satellite cameras’ impact has gone a long way. If you want to know what satellite cameras do, they perform three significant roles—Earth observation, navigation/geo-location, and telecommunications. Since the Earth is round, its cartography is very technical; it means that the images need to be flattened and assembled into a rational mosaic.
As you keep climbing up the sea level, the Earth’s curvature starts lessening; hence, planes, balloons, and satellites have given cartographers more room to breathe. However, this has also resulted in other problems. The optics need to be sensitive enough to capture the details precisely and sufficiently. It is also important to model and compensate for disturbances in the atmosphere.
Earth observation satellites were launched by France in 1985. These satellites were among the first to provide high-resolution images, strictly reserved for military and research uses. The reason these images had such strict audiences was the cost. Since these devices did not revisit the same place twice, the optics had to be oriented precisely. Additionally, the flattening of the images and various other processes was quite expensive, particularly compared to American satellites.
What Are The Applications Of Earth Observation Satellites Today?
Now that you know what is satellite camera is and its history is, let us jump back into the present. Remote sensing and Earth observation satellites have been used in a wide variety of fields and applications. Some of them include:
1. Disaster Prevention and Mitigation
Natural disasters can have a very devastating effect on people’s lives and are pretty difficult to assess at times. However, disaster risk assessment is required by the rescue workers. This data needs to be compiled and executed quickly and with utmost precision.
Satellite imagery can help with object-based classification via change detection before and after the event. Another critical application of using satellite imagery is measuring shadows from digital surface models and buildings.
2. Extracting Mineral Deposits
Satellite imagery and Earth observation also aid in mineral exploration. It is essential to know about the mineral potentiality in a given area for mineral extraction. With the help of satellite cameras, geoscientists can map the potential mineral zones, thereby saving a lot of time. The geologist will also narrow down geophysical and geochemical activities to point out high potential zones.
3. Agriculture Development
Agriculture is an important sector worldwide; as the population keeps increasing, so should agricultural production. You need to use satellite data to learn about the quantity, quality, and location of resources.
Satellite imagery and GIS will always be a part of the agricultural world. Data is continuously gathered related to agricultural resources like livestock, rangeland, crops, etc.
Final Thoughts
You can now see the various benefits of satellite cameras today. However, this would not have been possible if this space technology sector did not have its humble beginnings. We’re advancing minute by the minute thanks to the significant inputs provided by such technology.
What do you think of all this? Let us know in the comments!
