Earth-observation satellite

An Earth-observation satellite is an uncrewed spacecraft designed to collect information about Earth's natural resources and environmental conditions. These satellites use multispectral sensors to observe various characteristics of Earth's land and water surfaces, providing data valuable for mapping, resource management, and monitoring pollution levels.123

The first Earth-observation satellites, part of the U.S. Landsat program, were launched in 1972. They carried cameras, including infrared sensors, to capture images of surface areas at regular intervals, offering a more comprehensive survey than aerial photography. Subsequent satellites have incorporated advanced sensors like thematic mappers for higher spatial resolution. Remote sensing from satellites has applications in civilian and military sectors, including meteorology, navigation, and national security.12