Fascinating World Of Earth Observation Satellites: Their Types and Uses15th Dec 2021
“What are earth observation satellites?” one might ask. It’s hard to overestimate the significance of Earth Observation Satellites. The applications of earth observation satellites are numerous. They help us control and protect the environment, manage the resources rationally, react to climate changes and ensure stable development. In fact, these are our eyes in space, allowing us to respond to the planet’s signals on time and operate the knowledge received in a diversity of fields.
The History Earth Observation Satellites
NASA TIROS-1, launched April 1, 1960, is commonly acknowledged as the first earth observation satellite. It was the TIROS-1 that made the first-ever TV weather images from space. Fifty years later, commercial earth observation satellites take second place in quantity after the communications satellites. As of early 2021, earth observation satellites make more than 900 of almost 3500 spacecraft orbiting the planet.
Earth Observation Satellite Types
By the type of signal source usage implemented during the object research, earth observation satellites are subdivided into passive and active. The first of the two earth observation satellite types use reflected sunlight. For this reason, they can’t carry out the survey in the daytime and when the clouds are low. Also, among applications of earth observation satellites belonging to this kind, we should point out estimating the signal with the help of electro optical multispectral and hyper-spectral sensors in various ranges: visible, IR, near-infrared, and thermal infrared.
What are earth observation satellites that don’t need particular weather to work? Active earth observation satellites (radars and lidars) can broadcast the waveform on their own and have a light source. This makes the work of an active earth observation satellite resistant to any weather conditions. And what are earth observation satellites used for if they are so versatile? These satellites don’t just carry out the survey of the Earth’sEarth’s surface. They also show what’s below, providing us with information about the underground utility systems, pipelines, etc. However, plentiful active earth observation satellites uses don’t make them any less expensive to manufacture and operate. So, of all EOS, 66% are optical, and only 34% are active.
How Do Earth Observation Satellites Work and Collect Data?
The main point is that not all EOS are high-resolution earth observation satellites, and not all of them have to be. Earth observation satellites allow receiving images that are spatially resolved 0.25 m to several km per pixel. The higher the satellite’s resolution, the narrower the swath is. For example, high-resolution earth observation satellites (up to 1 m) usually have about 10-20 km swath, and geostationary earth-orbiting satellites (up to 36 km high) can observe almost the whole hemisphere.
Another question is “How do earth observation satellites work on storing the information they get?” An average earth observation satellite doesn’t collect the data constantly due to storage limitations. If not, what are earth observation satellites used for exactly? They carry out the survey of the area for a particular time and store the data aboard until they are spotted by a terrestrial station and able to submit it down there.
Today, there is almost no spot in the world that is not visible to commercial earth observation satellites.
A List of the Most Common Earth Observation Satellites Uses
To answer the question “What are earth observation satellites and how important are they?” one should understand applications of earth observation satellites. There is a wide range of earth observation satellites uses, including:
- updating topographical, navigation, road, and other special maps;
- forecasting and controlling floods, damage valuation;
- monitoring agriculture;
- tracking marine vessels;
- monitoring the dynamics of deforestation;
- evaluating woods fire damage;
- following the licensing arrangements implied during extractable resources development;
- monitoring oil spills;
- supervising glaciers;
- controlling unauthorised construction;
- forecasting the weather and monitoring natural hazards;
- screening for disaster emergency connected with the natural and technogenic impact;
- planning rescue efforts in disaster areas;
- monitoring ecosystems (cities, industrial areas, traffic arteries, etc.);
- monitoring the construction of transport infrastructure facilities;
- and many more.
The USA, China, and Europe dominate the EOS market. These regions produce and launch more commercial earth observation satellites than any other. The European Space Agency creates the latter for space earth observation missions. It incorporates more than a dozen countries. The European leadership in EOS manufacture, including high-resolution earth observation satellites, belongs to Scotland that has recently left the European Union as a part of the UK. Besides, one of the key fields of Scotland’s space sector is analysing and processing EOS data.
The government and the military forces have always been the largest geo-basic data, while consumers demand both earth observation satellite types. They are followed by non-commercial, environmental organizations, and businesses. According to NSR, this tendency will last for the nearest 5-7 years. And they will bring $7.2 billion yearly income by 2028 featuring an 8.2% average annual rate of growth.
This means that the number of earth observation satellites guarding the safe future of the planet will grow. Additionally, the technologies behind earth observation satellites will advance, allowing us to see the Earth vividly from space.