The secondary research process involved comprehensive analysis of regulatory databases, peer-reviewed scientific journals, technical publications, and authoritative space and geospatial organizations. Key sources included the US National Aeronautics and Space Administration (NASA), National Oceanic and Atmospheric Administration (NOAA), United States Geological Survey (USGS), European Space Agency (ESA), Japan Aerospace Exploration Agency (JAXA), Indian Space Research Organisation (ISRO), United Nations Office for Outer Space Affairs (UNOOSA), Group on Earth Observations (GEO), International Society for Photogrammetry and Remote Sensing (ISPRS), American Society for Photogrammetry and Remote Sensing (ASPRS), IEEE Geoscience and Remote Sensing Society (IEEE GRSS), Copernicus Programme (EU), United Nations Platform for Space-based Information for Disaster Management and Emergency Response (UN-SPIDER), National Geospatial-Intelligence Agency (NGA), US Department of Defense (DoD) Space Development Agency, Defense Advanced Research Projects Agency (DARPA), European Union Agency for the Space Programme (EUSPA), Food and Agriculture Organization (FAO) of the United Nations, World Meteorological Organization (WMO) Integrated Global Observing System, and national space agency reports from key markets.
These sources were employed to compile satellite launch statistics, regulatory approval data for commercial remote sensing systems, technical performance studies, defense procurement data, climate monitoring initiatives, and market landscape analysis for satellite-based remote sensing, aerial sensing platforms, ground-based sensing systems, and drone-based sensing technologies.