There are thousands of launched satellites in space orbiting the earth constantly collecting valuable data.
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Remote sensing is acquisition of information about objects that are far away. Usually satellites and drones are used to collect the data, but airplanes and helicopters could also be an option. If we collect such data regularly over the course of time, it is possible to analyze the changes in observed objects or phenomenons through time. Such knowledge gives us deep understanding on how particular things change in nature, or for example: how cities develop. Moreover, besides gaining a clear picture of what was happening on our planet over time, it also becomes feasible to predict the future. For example: observe the rate of melting arctic ice or in case of large forest fires predicting in which direction the fire will spread in the next couple of days. There is a lot of research happening in the acquisition of precise images and some companies even manage to completely photograph the entire planet surface every single day using constellations of multiple satellites.More Info