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Landsat 7
Value Added Processors Workshop
March 4, 1999
USGS National Center
Reston, VA.


Meeting convened at 9:05am by D. Lauer (USGS/EDC)

I. Landsat Program Overview - Role of the Landsat 7 Management Team: D. Lauer


IB. Landsat Program Overview: D. Thibault (Earth Satellite Corporation)


II. Landsat 7 system overview: D. Williams (NASA/GSFC)
General comments:

  1. Landsat history
  2. Level 1 requirements
  3. Landsat 7 system concept SEE CHART
  4. Landsat 7 system
    1. Landsat 7 Spacecraft: Built by Lockheed Martin Missiles and Space (LMMS) Three axis stabilized platform designed to carry the ETM+ and provide support functions of power generation, thermal control, communications, and data storage for instrument and spacecraft
    2. Enhanced Thematic Mapper Plus (ETM+) Instrument: Built by Raytheon, Santa Barbara Remote Sensing (SBRS); An eight band, mechanically scanning radiometer; ETM+ is a fixed position, nadir viewing, "whisk-broom", multispectral scanning radiometer capable of providing high-resolution imaging information of the Earth's surface in both the visible and infrared regions of the spectrum
      • Eight spectral bands with resolutions between 15 to 60 meters, each having individual high and low gain settings
      • Absolute radiometric accuracy of 5%; three on-board calibration devices
      • Full Aperture Calibrator (FAC), Partial Aperture Calibrator (PAC), and On-board Calibrator (OBC)
      • 2 x 75 Mbps data channels
      • 183 km wide swath
      • Radiative cooling for cold focal plane / infrared sensors
    3. Mission Profile
      • Delta II launch from Western Test Range, VAFB on April 15, 1999
        • Launch window is 18:32 to 18:34 GMT; or 11:32 to 11:34 VAFB (PDT) time
        • 705 +/-5 km, 98.2 degree sun-synchronous, 10 am +/- 15 minute nodal crossing, descending orbit
        • 16 day repeat cycle on the World Reference System (WRS)
        • 5 year design life; expendables for 6 years
        • 72 hour autonomous survival capability
    4. Related Missions
      • EOS AM-1 will fly in formation ~30 min. behind Landsat 7 (July '99)
      • NMP EO-1 will fly in formation ~1 min. behind Landsat 7 (~ Dec '99)
    5. Delta II launch vehicle SEE CHART
    6. Launch profile SEE CHART
    7. Landsat 7 spacecraft SEE CHART
    8. Spacecraft Subsystems
      • Power Subsystem
        1. 2x50 amp-hour Nickel-Hydrogen batteries
        2. Single sun tracking solar array with output of 2,230 watts
        3. 28 volt regulated bus with direct energy transfer capability
      • Attitude Control Subsystem
        1. 3 axis stabilized with a Honeywell IMU, Honeywell reaction wheels, Ithaco torque rods, Barnes earth sensor, Adcole coarse sun sensors and a Honeywell celestial sensor
        2. Pointing Control ; 60 arcsec (per axis)
        3. Pointing Knowledge ; 45 arcsec (per axis)
      • Propulsion Subsystem
        1. 12 one pound thrusters (6 primary/6 redundant)
        2. 31 inch tank holds 269 pounds of hydrazine with redundant latch valves
        3. 149 pounds of hydrazine required for the 5 year mission
      • Command & Data Handling Subsystem
        1. Redundant 1750 processors with cross strapped data bus
        2. Real Time Command Storage (RTCS) capability for operational and contingency modes
        3. Autonomous Failure Detection and Correction, including sun-pointing safe hold mode
        4. 378 Gbyte L3 Communications Solid State Recorder (SSR) ~100 scene storage capability
      • Communications Subsystem
        1. Two S-band Omni antennas (Zenith/Nadir) with 5 watt Motorola transponders for command and telemetry
        2. Three Gimbaled X-band antennas with four switchable 3.5 watt transmitters (150 Mbps each) for high rate instrument data
        3. Capable of transmitting two 150 Mbps data streams to a single location plus one 150 Mbps data stream to a different location or three 150 Mbps data streams to three different locations
      • Thermal Control Subsystem: Passive proportional control with thermal blankets, radiators, heaters and thermostats.
    9. Baseline X-band downlinks SEE CHART
  5. Landsat 7 status
  6. Waivers of note: Level 1 Requirements Waivers:
  7. Performance waivers:
  8. Long term acquisition plan (LTAP) highlights
  9. Other items worth noting


IIB. Landsat 7 Ground System Status: RJ Thompson (USGS/EDC)
Comment: Several key decisions in the Landsat 7 program including the provisions for high latitude and mid latitude stations and generation of L0 and L1 products, are the result of efforts by Darrel Williams, and we owe him our thanks.

  1. Ground System Objectives
  2. System Integration and Test Activity
  3. International Cooperator Network (estimated)
  4. Product Generation and Distribution Capability

  5. Standard Product Availability
    Product Available Quantity Turnaround Community Price
    L0R L+60 1-100/day 24 hrs Any User $475
    L1R L+60 1-100/day 48 hrs Any User $600
    L1G L+60 1-100/day 48 hrs Any User $600
    L1P L+90 60/day 72 hrs TBD TBD
    L1T L+90 60/day 72 hrs TBD TBD
    Notes: 1) L0R turnaround measured from data acqusition (add 72 hours for data acquired at ASGS/SGS) to product staged for shipment. 2) L1 turnaround measured from L0R source available to product staged for shipment (assuming control/terrain model available)

  6. Contingency Planning
  7. Upcoming Events


III. Landsat 7 data policy: R. Byrnes (USGS)

  1. Business Partner Program Summary (existing)
  2. Landsat data policy


IV. Data products and formats - R. Johnson (Raytheon Systems Company)

  1. L7 Data Products and Formats
  2. Landsat 7 Product Levels
  3. Level 0R Product
  4. Level 0R Product Components
  5. Calibration Parameter File
  6. Level 1R Product
  7. Level 1R Product Components
  8. Level 1G Product
  9. Level 1G Product Options
  10. Level 1G Product Options
  11. Data Product Packaging
  12. Data Product Access and Distribution
  13. Contact Information and References


V. L7 software availability - J. Irons (NASA/GSFC)
Comment: Until recently, some of the source code for L7 has been stored on open FTP sites at GSFC. Those sources have been closed until formal approval for software distribution is obtained. At that time, the code for the LPS, IAS and LPGS will be made available at no cost. The approval process takes about 6 weeks, but may take longer. Hope is to have it available soon after launch

  1. Science Data Processing Source Code
  2. LPS, IAS, & LPGS Functions
  3. Notes
  4. Access to documentation


Afternoon session
The plenary session re-convened at approximately 1:10pm. The commercial sector attendees were divided into four break out groups. The groups met in separate rooms. Each group, assisted by a meeting facilitator (non-government person) and subject matter expert, was asked to address the following four questions and report back to the plenary session later in the afternoon.

  1. Based on this morning's presentations, what opportunities for value added processors sound most promising?
  2. What potential barriers do Landsat program managers need to address to enable your organization to take advantage of such opportunities?
  3. Which of the following Landsat 7 data products do you feel should be available to all customers from the USGS?
  4. What major concerns about the Landsat 7 program do you have that have not been addressed in this workshop but need to be addressed in the future?

The plenary session reconvened at 3:30.


Group Reports:

A. "Green" group: Jon Dykstra (Earth Satellite Corp.)
Answers to questions:

  1. Best opportunities for value added processors (number selecting that option):
  2. Potential barriers Landsat Program Managers need to address
    1. USG shouldn't migrate to higher level processing
    2. USG shouldn't compete with commercial sector by using government assets
    3. Getting access to "global archive" - one place to go to get information on what is available everywhere.
    4. Need common definition of processing levels
    5. USGS support education and benefits of use of Landsat data (and other remote sensing data)
    6. Need to minimize turn around time for the data. EDC should focus on getting the data out quickly, not on producing 1P/T products.
    7. USG should not give away Landsat data - preserve economic value
    8. Landsat Program Management should give six months notice of change in data prices
  3. What level ''0' &'1' products should be available from the USGS?
  4. Other Landsat 7 program issues that need to be addressed?

B. "Silver" group: Mark Lucas (Imagelinks)

Answers to questions:
  1. Best opportunities for value added processors: (group ranking)
  2. Potential barriers Landsat Program managers need to address
  3. What level '0' & '1' products should be available to all from USGS?
  4. Other Landsat 7 program issues that need to be addressed?

C. "Red" group: Marshall Faintich (Orbimage)

D. "Blue" group: Andrea Gallagher (Research Systems) Comment: Coming from perspective of end -users. Group was mainly data providers.
Answers to questions:

  1. Best opportunities for value added processors (in priority order):
  2. Potential barriers Landsat Program managers need to address:
  3. What level '0' & '1' products should be available to all from USGS?
  4. Other Landsat 7 program issues that need to be addressed?

Commentaries from M. Felsher and K. Green followed. [Refer to top of page for links to those presentations]

Final comment from D. Lauer:
USGS is vested in this program (NOAA had no real interest in land data) If government agency people were asked to a workshop like this, the answers received would probably be quite different. Same with academics, as with state and local government. USGS is being pulled in different directions by different elements of the user community. The mind set of USGS is not to creep up the ladder of data processing. USGS is trying hard not to compete with commercial vendors. USGS is committed to helping the private sector.

What happens next? Information form this meeting will go on the "vameet" website, including attendance list.

Question from P. Norris: It would be helpful for this community if USGS would indicate future growth of sales of products. What are the goals of USGS in supporting the Landsat market place. D. Lauer - NMD and EDC have strategic plans on line. Please refer to them.

Workshop adjourned at approximately 4:50pm.

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