# Business Intelligence through Machine Learning from Satellite Remote Sensing Data
## 2 Satellite Systems in Remote Sensing
### Overview of Major Satellite Missions and Their Derived RS Products  
In this section, we introduce selected major satellite missions across the United States and Europe. We also introduce latency and processing levels related to data products and describe their use cases in remote sensing applications, as well as their differences. At least 77 government space agencies are operating as of 2022, 6 of which (NASA (USA), ESA (EU), CNSA (China), ISRO (India), JAXA (Japan), and RFSA or Roscosmos (Russian)) have launch capabilities. Besides NASA, in the United States, two other major federal agencies are involved in Earth observation satellites, USGS and NOAA. The **USGS** scans the whole surface of the earth with a 30 m resolution approximately every two weeks, including atmospherically corrected multispectral and thermal data, It has been used widely in remote sensing for shoreline mapping, forest monitoring, disaster management, and precision agriculture, to name a few. The **NOAA** operational satellite system for environmental monitoring consists of geostationary and polar-orbiting satellites. The Geostationary Operational Environmental Satellite (GOES) server is mainly used for national, regional, and short-range warning and \"nowcasting\", while the polar orbiting ones, such as Polar Operational Environmental Satellites (POES) and the Suomi National Polar Orbiting Partnership (Suomi-NPP), are used for long-term forecasting and environmental monitoring on a global scale. The VIIRS, one of the key sensors of the Suomi-NPP satellite, has been actively used for fire monitoring, urban expansion, and economic development monitoring. It is a scannerradiometer that measures Earth radiation on the surface and atmosphere levels in the visible and infrared spectra. VIIRS has different spatial resolutions among the data that it collects among 22 different spectral bands of 750 m and 375 m at nadir. Its Day/Night Band (DNB), is ultrasensitive to low-light conditions and enables the generation of quality nighttime products with substantial improvements compared with older systems (DMSP/OSL). **EU** features the EUMETSAT Polar System that consists of Metop, three polar-orbiting meteorological satellites that orbit the world via the poles from an altitude of 817 km and continuously collect data. These satellites carry eight main instruments, and their collected data are essential for climate monitoring and weather forecasting. ESA operates the Copernicus Program, which includes the development of the sentinel satellites, a constellation of satellites responsible for various satellite missions of different purposes. For example, Sentinel 5p provides data for the quality of air, while Sentinel 3 is responsible for climate and environmental monitoring. For revisit and coverage purposes, each Sentinel mission is built on a constellation of two satellites that offer a higher temporal frequency. In the case of Sentinel-2, for example, S2-A and S2-B offer a combined 5-day revisit time. Apart from the various government-launched successful satellite missions, many private organizations are also innovating the remote sensing space, offering very high spatial and temporal resolution imagery. **Planet Labs** specializes in public Earth imaging that aims to provide daily monitoring of the entirety of Earth and pinpointing trends [5]. They design and manufacture Doves, which are Triple-CubeSat miniature satellites that get into orbit as payloads on other rocket launch missions and are equipped with high-performance devices (telescopes and cameras) that capture different swaths of Earth and send high-quality data to a ground station. Dove-collected images, which provide information for climate monitoring, precision agriculture, and urban planning, can be accessed online and sometimes fall under the open data access policy. They have roughly 200 satellites in orbit that offer crucial services for disaster management and decision making in general.