Defense Meteorological Satellite Program (DMSP) Satellite F13 Source/Platform

 

Summary:

This document contains information about the DMSP F13 Satellite. The DMSP F13 satellite is a in a near circular, sun synchronous, polar orbit. The DMSP mission is to provide global visible and infrared cloud data and other specialized meteorological, oceanographic and solar-geophysical data in support of world wide Department of Defense (DoD) operations. A description of the mission is provided as is information about the spacecraft and its environment. The ground data system is briefly described.

Table of Contents:

1. Platform or Data Collection Environment Overview:

Platform or Data Collection Environment Long Name, Platform Acronym:

Defense Meteorological Satellite Program (DMSP) Block 5D-2 Satellite F13, DMSP F13

Platform Introduction:

DMSP, originally known as the Defense System Applications Program (DSAP) and the Defense Acquisition and Processing Program (DAPP), is a long-term USAF effort in space to monitor the meteorological, oceanographic and solar-geophysical environment of the Earth in support of DoD operations. All spacecraft launched have had a tactical (direct readout) and a strategic (stored data) capacity. In December 1972, DMSP data was declassified and made available to the civil/scientific community. The USAF maintains an operational constellation of two near-polar, sun-synchronous satellites

Collection Environment:

Satellite

Platform Program Management:

The DMSP program office is located at the Space Systems Division, Air Force Material Command, Los Angeles Air Force Station, Los Angeles, California 90009-2960. Funding is provided by the Department of Defense (DoD).

Platform Mission Objectives:

The DMSP mission is to provide global visible and infrared cloud data and other specialized meteorological, oceanographic and solar-geophysical data in support of world wide Department of Defense (DoD) operations.

Platform Parameters:

DMSP Satellite F13 was built by General Electrics Astro-Space Division (now part of Martin Marietta Astro Space). It was launched on March 24, 1995 from Vandenberg AFB, California using an Atlas E rocket. The spacecraft is 3.7 meters in length with a diameter of 1.2 meters with an on-orbit mass of 831 kilograms. It has a design lifetime of 48 months. Power is provided though a 9.29 sq-m solar cell panel. Attitude is controlled using momentum wheels and magnetic coils using a strap-down star sensor and gyros as the reference.

Coverage Information:

DMSP Satellite F13 is in a near circular, sun synchronous, polar orbit.

  • Maximum Altitude: 856 km
  • Minimum Altitude: 844 km
  • Inclination: 98.8 deg
  • Period: 102.0 minutes
  • Eccentricity: 0.00083
  • Ascending Equator Crossing Time (Local Time):
    • At Launch: 17:42
    • Current (09/02/95): 17:43
  • Swath Width:
    • Visible and Infrared Imagery - 3000 km
    • Microwave Imagery - 1400 km
    • Temperature Sounder - 1500 km
    • Water Vapor Profiler - 1500 km
  • Launch Date - March 24, 1995
  • End Mission (Operational Support - F13 is currently (9/02/95) providing primary support with sensors OLS, SSM/I, SSM/T, SSM/T-2, SSJ/4, SSIES2, SSM, SSB/X and SSZ still providing data.

Attitude Characteristics:

Pointing Accuracy: 0.01 deg (primary), 0.12 deg (backup)
Stability: maximum rate - 0.03 deg/sec per axis.

Short term changes in attitude are measured using three orthogonal gyroscopes. A strap down star sensor is used to bound the effects of gyroscope drift. The desired attitude is computed based upon a star catalog and an ephemeris table up-linked to the spacecraft daily. Three-axis attitude control is maintained in the orbital configuration by automatic momentum exchange between three momentum wheels. On-board magnetic coils provide controlled interaction with the earth's magnetic field to prevent the accumulation of wheel secular momentum. Operations of these coils is under control of the closed loop spacecraft attitude control system. Both the momentum wheels and gyroscopes are backed up by a fourth skewed unit for redundancy.

Data Collection System:

Data is transmitted in real time to tactical terminals world-wide. Data is also stored using on-board recorders for transmission to and processing by the Air Force Global Weather Central (AFGWC), Offutt AFB, Nebraska and the Fleet Numerical Meteorology and Oceanography Center (FNMOC), Monterey, California. Both AFGWC and FNMOC relay the SSM/I, SSM/T and SSM/T2 data to the National Environmental Satellite, Data, and Information System (NESDIS). AFGWC also sends the entire data stream to the National Geophysical Data Center (NGDC).

Communication Links:

DMSP uses S-band links at 1.024 Maps for the tactical real time transmissions. Stored data are transmitted at 2.66 Mbps to receiving sites at

  • Fairchild AFB, Washington
  • Thule, Greenland
  • AF Remote Tracking Station, Hawaii and the
  • New Hampshire Tracking Station.

Data are then relayed at 3.072 Mbps via commercial geostationary communications satellite to AFGWC and FNMOC. Spacecraft commanding is done at L-band at a 2 Kbps rate.

List of Sensors/Instruments:

  • OLS - Operational Linescan System
  • SSM/I - Special Sensor Microwave Imager
  • SSM/T - Special Sensor Microwave Temperature Sounder
  • SSM/T-2 - Special Sensor Microwave Water Vapor Profiler
  • SSIES - Special Sensor Ion and Electron Scintillation Monitor
  • SSJ/4 - Special Sensor Precipitating Electron and Ion Spectrometer
  • SSB/X-2 - Special Sensor Gamma/X-Ray Detector
  • SSM - Special Sensor Magnetometer
  • SSZ - TBD

2. Ground Segment Information:

Tracking and Control:

DMSP satellite command and control is performed by the 6th Satellite Operations Group at Offutt AFB, Nebraska.

Data Acquisition and Processing:

Data is transmitted in real time to tactical terminals world-wide. Data is also stored using on-board recorders for transmission to and processing by the Air Force Global Weather Central (AFGWC), Offutt AFB, Nebraska and the Fleet Numerical Meteorology and Oceanography Center (FNMOC), Monterey, California. Both AFGWC and FNMOC relay the SSM/I, SSM/T and SSM/T2 data to the National Environmental Satellite, Data, and Information System (NESDIS). AFGWC also sends the entire data stream to the National Geophysical Data Center (NGDC).

Latitude Crossing Times:

Ascending Equatorial Crossing Time (Local Time):
  • At Launch: 17:42
  • Current (09/02/95): 17:43

3. References:

4. Glossary of Terms:

Please see the GHRC Glossary for terms related to the GHRC and see EOSDIS Acronyms for a general listing of terms related to the Earth Observing System Project.

5. List of Acronyms:

Please see the GHRC Glossary for terms related to the GHRC and see EOSDIS Acronyms for a general listing of terms related to the Earth Observing System Project.

6. Document Information:

Document Revision Date:

May 29, 1997

Document Review Date:

September 19, 1995

Document ID:

DMSP F-13 Platform Document

Document Curator:

GHRC User Services
ghrc@eos.nasa.gov

Document URL:

 
http://microwave.msfc.nasa.gov:5721/source_documents/dmsp_f13.html