GeoEye-1, formerly known as OrbView-5, is the next-generation high-resolution imaging mission of GeoEye, Dulles, VA, USA. In January 2006, the commercial imaging company GeoEye was formed, made up of ... former Orbimage of Dulles VA, and of former Space Imaging of Thornton, CO (Orbimage acquired Space Imaging in 2005 and gave the merged company the new name of GeoEye). The newly formed GeoEye company is the world's largest commercial satellite imagery provider.
On Sept. 30, 2004, OrbImage was awarded a NextView vendor contract of NGA (National Geospatial-Intelligence Agency). The contract, referred to as NextView OrbImage, provides long-term revenue commitments as well as capital for the development of OrbView-5. NGA's NextView program is designed to give US commercial imaging satellite operators the financing to build their satellites for high-resolution imaging.
GeoEye's principal partners for the development and launch of the GeoEye-1 satellite include General Dynamics (formerly Spectrum Astro), ITT Industries (imager), and Boeing Launch Services. GeoEye's partners for the ground segment include IBM and MDA (MacDonald, Dettwiler and Associates) of Richmond, BC, Canada.
he GeoEye-1 spacecraft is being designed and developed at General Dynamics/C4 Systems of Gilbert, AZ (formerly Spectrum Astro) as prime contractor. The contract was award in Dec. 2004. The spacecraft design is based on the SA-200HP standard modular bus (of Coriolis and SWIFT heritage). The spacecraft is 3-axis stabilized with a sophisticated attitude control system to provide a highly stable, while also highly agile imaging platform.
A body-pointing capability of up to ▒ 60║ is being provided, made possible by enhanced reaction wheels (low jitter). The image geolocation accuracy is ? 3 m. The spacecraft mass is 1955 kg (bus mass = 1260 kg), the S/C design is fully redundant with an operational life of 7 years (the expected life is 10 years).
Orbit: Sun-synchronous circular orbit, altitude = 684 km, inclination = 98║, period = 98 minutes, local equatorial crossing at 10:30 hours, effective revisit time capability ? 3 days.
Launch: A launch of GeoEye-1 is scheduled for August 2008 on a Delta-2 (7420-10) vehicle from VAFB, CA. The launch provider is ULA (United Launch Alliance). The launch delay from the fall of 2007 is due to a launch congestion at VAFB.
RF communications: The source data are being stored on solid-state onboard recorders of 1.2 Tbit capacity. The downlink of imagery in X-band at 740 Mbit/s (or at 150 Mbit/s), the TT&C data are in S-band. The S/C is being operated from the command and control facility at GeoEye headquarters in Dulles, VA, along with an imagery acquisition station. Three other acquisition stations will be operated or leased by GeoEye in Barrow, AK, Troms°, Norway and Troll, Antarctica (the TrollSat station is located at 72║ S and 2║ E). The latter two stations are being leased from KSAT (Kongsberg Satellite Services) of Troms°, Norway.
A total of four stations are needed to handle primary data reception due to the large volume of data that will be captured by the satellite. In addition, GeoEye will continue to support a network of receiving stations owned and operated by local business partners, referred to as Regional Affiliates and Regional Distributors.
Ground segment: GeoEye has built a fully integrated receiving, processing, and distribution network for delivering high-quality imagery products to customers around the world.
In late 2006, GeoEye purchased high-bandwidth, high-performance compute technology from SGI (Silicon Graphics Inc.). Four SGI Altix systems were installed at the Dulles (VA) ground station for data processing, distribution, and archiving services.
Sensor complement: (GIS)
The requirements of GeoEye-1 call for panchromatic imagery with a resolution of 0.41 m and multispectral imagery with a resolution of 1.64 m. The imager is being designed and developed by ITT Space Systems Division, formerly Kodak Remote Sensing Systems of Rochester, New York, which built also the sensor for Ikonos-2 (launch April 27, 1999). In January 2007, the GeoEye-1 imager system was delivered to General Dynamics for integration into the spacecraft.
GIS (GeoEye Imager System). GIS is a pushbroom imaging system whose basic elements are the optics subsystem (telescope assembly), the focal plane assembly (CCD detector), and the digital electronics subsystem. The optics subsystem employs a TMA (Three Mirror Anastigmatic) telescope design with a primary mirror aperture of 1.1 m in diameter. Three mirrors are used to image and focus the light, and two additional mirrors to direct the image to the FPA (Focal Plane Assembly). The telescope is designed to give a near-perfect (diffraction limited) image to the FPA and to convert the analog pixels into digitized signals.
The FPA consists of an array of CCD detectors with 8 Ám pixel size for PAN and 32 Ám pixel size for multispectral imagery. ITT has included an outer barrel and door assembly to help protect the telescope and maintain its thermal environment.