
The payload of a satellite refers to all the instruments that the satellite needs to do its job. This includes: antennas, sensors, cameras, radar and other electronic components.
Transporter (bus) is the part of the satellite that transports, as the name implies, the payload and all its equipment; keeping all parts of the satellite together in a single structure and provides the electrical power that feeds the internal computer and propulsion system of the object.
According to the Union of Concerned Scientists (UCS), by January 1, 2021, a total of 3,372 satellites were estimated to be in operation. These satellites can be used for a wide variety of purposes and many are designed to perform a specific activity. Thus, we can find in orbit astronomical, communication, navigation and geolocation (GPS), telecommunications, military, earth observation, meteorological and space station satellites.

The technology behind earth observation satellites is amazing. Their remote sensing sensors survey the earth’s surface and from an altitude of up to 480 km (300 miles), they use powerful cameras to scan the planet, from which we can obtain important information about the levels of air pollution, water bodies and deforestation in different regions of the planet.