Earth Observation/Remote Sensing Satellites
Two major players in satellite-based Earth imagery are U.S. companies DigitalGlobe and GeoEye. Both companies provide imagery to widely used applications such as Google Earth. In August 2010, the U.S. National Geospatial-Intelligence Agency (NGA) awarded 10-year contracts to the companies, valued at $## billion for GeoEye and $## billion for DigitalGlobe, under the agency’s EnhancedView procurement. The NGA specializes in mapping and imagery intelligence, and played a key role in the raid on Osama bin Laden’s compound in May 2011 by providing satellite imagery, geospatial and targeting analysis, and modeling support to plan the successful mission.
In June 2010, Israel launched the OFEQ-9 reconnaissance satellite which joined ## others already in operation. China’s utilization of space for military purposes is even harder to gauge due to the country’s lack of transparency in its space programs. In 2010, the country launched ## Yaogan satellites with the stated purpose of engaging in scientific experiments, land survey, crop yield assessment, and disaster monitoring. Many space analysts believe that the true mission of these satellites is for reconnaissance or other military purposes.
Concerns about global climate change have led to the use of remote sensing satellites to measure the potential impact of humans on the environment. NASA employs more than a dozen Earth science spacecraft measuring a variety of environmental factors, including sea level, the amount of aerosols in the atmosphere, and changes in the size of the Earth’s ice sheets. The United States and Taiwan have partnered to develop the six-satellite FORMOSAT fleet, used to collect atmospheric data for weather prediction and for ionosphere, climate, and gravity research.
Two major U.S. commercial providers of satellite-based Earth imagery are DigitalGlobe and GeoEye. Both companies provide imagery for widely used applications such as Google Earth. In August 2010, the companies were awarded separate 10-year, $## billion contracts from the U.S. National Geospatial-Intelligence Agency under that agency’s EnhancedView procurement. These contracts make it possible for both companies to finish procurement and launch of new advanced satellites capable of discerning objects on the Earth’s surface as small as 25 centimeters (9.75 inches) in size.
NASA operates or participates in more than a dozen remote sensing satellites and international programs. The Jason satellite, a joint mission between France and the United States that follows the highly successful TOPEX/Poseidon altimeter mission, has measured an increasing rate of sea level rise. Data from the Ice, Cloud, and land Elevation Satellite (ICESat) and Gravity Recovery and Climate Experiment (GRACE) satellites have shown rapid changes in the Earth’s ice sheets.
In 2008, there were ## remote sensing satellites launched on behalf of ## countries. Of particular note, in August, the German RapidEye constellation of ## remote sensing satellites was launched. The ## RapidEye satellites travel along the same orbital plane and feature identical sensors, allowing large amounts of imagery to be collected, up to ## million square kilometers (## million square miles) per day. ## satellites in the same orbital plane allow for a higher number of multiple imaging passes over the same spot and quick revisit times. With these capabilities, the RapidEye constellation is capable of imaging any point on Earth every day.