Sunday, September 14, 2008

GeoEye-1 est un satellite qui servira à Google Earth. Wow. Imaginez la suite...

GeoEye-1 will have the highest resolution of any commercial imaging system and be able to collect images with a ground resolution of 0.41-meters or 16 inches in the panchromatic or black and white mode. It will collect multispectral or color imagery at 1.65-meter resolution or about 64 inches, a factor of two better than existing commercial satellites with four-band multispectral imaging capabilities. While the satellite will be able to collect imagery at 0.41-meters, GeoEye's operating license from the U.S. Government requires re-sampling the imagery to 0.5-meter for all customers not explicitly granted a waiver by the U.S. Government.

Besides unsurpassed spatial resolution of 0.41-meters or about 16 inches, GeoEye-1 is designed to be able to offer three-meter geolocation accuracy, which means that customers can map natural and man-made features to within three meters (about 9 feet) of their actual location on the surface of the Earth without ground control points. This degree of inherent accuracy has never been achieved in any commercial imaging system and will remain unchallenged even when next-generation commercial systems are launched in the coming years.

GeoEye-1, a polar-orbiting satellite, will be able to revisit any point on Earth once every three days or sooner. Though it stands two stories high and weighs more than two tons, GeoEye-1 is designed to deftly train the ITT camera on multiple targets during a single orbital pass and is able to rotate or swivel forward, backward or side-to-side with robotic precision. This unrivaled agility will enable it to collect much more imagery during a single pass.

GeoEye-1 will make 15 orbits per day flying at an altitude of 681 kilometers or 423 miles with an orbital velocity of about 7.5 km/sec or 16,800 mi/hr. Its sun-synchronous orbit allows it to pass over a given area at about 10:30 a.m. local time every day. Given its altitude and sun-synchronous orbit, field of view and superior resolution GeoEye-1 can “revisit” any point on the globe every three days or sooner, depending upon the required look angle. The satellite will complement GeoEye's current IKONOS system and will collect imagery about 40 percent faster for panchromatic and 25 percent faster for multispectral collections. Together, the IKONOS and GeoEye-1 satellites can collect almost one million sq km of imagery per day.

In the panchromatic mode the satellite is capable of collecting up to 700,000 square kilometers in a single day, an area about the size of Texas, and in the multispectral mode 350,000 square kilometers per day; the equivalent of photographing in color the entire State of New Mexico. This capability is ideal for large-scale mapping projects. Our customers will have assured access to high-resolution, high-quality commercial imagery well into the 2015 timeframe.

GeoEye-1’s optical telescope, detectors, focal plane assemblies and high-speed digital processing electronics are capable of processing 700 million pixels per second. GeoEye-1's agile camera allows for side-to-side extensions of the camera's 15.2 kilometer (9.44 miles)-wide swath width or multiple images of the same target during a single pass to create a stereo picture. The camera and electronics represent a 5-times gain in power efficiency, a 10-times improvement in weight efficiency and 3-times advance in cost efficiency.

from GeoEye

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