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Old Value=[Text Source: NASA National Space Science Data Center, http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1997-037A ]

NSSDC ID: 1997-037A
Description

SeaStar was a spacecraft, developed by Orbital Sciences Corporation, to deliver daily, worldwide, high precision, moderate resolution, multispectral visible observations of ocean radiance for research in biogeochemical processes, climate change, and oceanography. A near noon sun-synchronous orbit was flown for optimum illumination of the lighted hemisphere. Data were taken from a single ocean color scanner on-board the satellite (SeaWiFS - Sea-viewing Wide Field-of-View Sensor). The SeaStar spacecraft was launched into low Earth orbit via a Pegasus launch vehicle which was flown under the wing of a modified Lockheed L-1011 aircraft. The spacecraft had an on-board hydrazine propulsion system which was used to raise the satellite to its final 705 km circular, noon, sun-synchronous orbit. Final orbit was achieved 20 days after launch. The spacecraft was three-axis stabilized by an Attitude Control System (ACS) which consisted of orthogonal magnetic torque rods for roll and yaw control and two momentum wheels for pitch stabilization. ACS sensors included redundant sun sensors, horizon sensors, and magnetometers. The propulsion system consisted of a reaction control subsystem for third stage stabilization and a hydrazine propulsion subsystem for raising the space- craft to its operational orbit and for orbit stabilization. Local high resolution (1 km) data (LAC) were delivered by direct broadcast at L-Band to regional scientific centers nationwide. Reduced resolution (4 km) data (GAC and selected LAC) were directly broadcast at S-band to smaller research centers and ships at sea. All reduced resolution data and selected full resolution data were recorded on board and transmitted to GSFC via daily dump at S-Band or via the Tracking and Data Relay Satellite System (TDRSS). A minimum three year mission life was expected.

The satellite stopped taking data on December 11, 2010 and was subsequently decommissioned.


Group: Platform_Details
   Entry_ID: SEASTAR
   Group: Platform_Identification
      Platform_Category: Earth Observation Satellites
      Short_Name: SEASTAR
      Long_Name: Orbital Sciences Corporation OrbView-2 Satellite
   End_Group
   Group: Synonymous_Platform_Names
      Short_Name: SeaStar
      Short_Name: Orbview
      Short_Name: 24883
   End_Group
   Group: Platform_Associated_Instruments
      Short_Name: SEAWIFS
   End_Group
   Group: Orbit
      Orbit_Altitude: 705 km
      Orbit_Inclination: 98.2 degrees
      Equator_Crossing: Noon +/- 20 minutes
      Period: 99 minutes
      Perigee: 707 km
      Apogee: 708 km
      Orbit_Type: LEO &gt; Low Earth Orbit &gt; Polar Sun-Synchronous
   End_Group
   Creation_Date: 2007-04-16
   Online_Resource: http://oceancolor.gsfc.nasa.gov/SeaWiFS/SEASTAR/SPACECRAFT.html
   Online_Resource: http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1997-037A
   Online_Resource: http://www.orbital.com/SatellitesSpace/ImagingDefense/OV2/index.shtml
   Online_Resource: http://oceancolor.gsfc.nasa.gov/SeaWiFS/
   Online_Resource: http://science.nasa.gov/missions/seawifs/
   Sample_Image: http://oceancolor.gsfc.nasa.gov/SeaWiFS/IMAGES/seastar_orbit.jpg
   Group: Platform_Logistics
      Launch_Date: 1997-08-01
      Launch_Site: Vandenberg Air Force Base, USA
      Design_Life: 5 years
      Primary_Sponsor: USA/NASA
      Primary_Sponsor: Orbital Sciences Corporation
   End_Group
End_Group
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text: OrbView-2
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    <skos:definition xml:lang="en">OrbView-2 is an imaging satellite, developed, owned, managed and operated by Orbital Imaging Corporation (OrbImage) of Dulles, VA. The overall objective of the OrbView-2/SeaWiFS mission is to provide quantitative data on global ocean bio-optical properties to the Earth science community. The OrbView-2 satellite includes the SeaWiFS (Sea-Viewing Wide Field-of-View Sensor) imaging system, an 8-band multispectral imaging instrument with a one kilometer spatial resolution.</skos:definition>
    <dcterms:modified>2020-01-29 16:58:54.0</dcterms:modified>
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