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Shuttle Radar Topography Mission




Shuttle Radar Topography Mission
Update 3/14/00

Mission Statistics:
Launch: February 11, 2000, 12:44 pm EST
Landing: February 22, 2000, 6:22 pm EST at Kennedy Space Center
Mission Duration: 11 days, 5 hours, 38 minutes
Project Start: August 1996
Project End: March 2001
Project Life Cycle: 60 months (42 months start to launch; 18 months data processing)

Data Statistics
Land coverage: Targetted land was 80% of Earth landmass (119.56 M km2, 46.16 M mi2)
99.968% targetted land mapped at least once (119.51 M km2, 46.14 M mi2)
94.59% targetted land mapped at least twice (113.10 M km2, 43.66 M mi2)
49.25% targetted land mapped at least 3 times (58.59 M km2, 22.73 M mi2)
24.10% targetted land mapped at least 4 times (28.81 M km2, 11.12 M mi2)

Land area missed: 50,000 km2 (all in US)

Data Takes: 765 total
399 C-band only
1 X-band only
365 C and X-band simultaneous
674 data takes over land
61 Built In Test Equipment (BITE) data takes
28 'short' ocean calibration data takes
2 'long' ocean calibration data takes

Data Tapes: 330 total high-density tapes used
208 tapes with C-band data, plus one double-recorded (pilot) tape
122 tapes with X-band data, plus one double-recorded (pilot) tape
(C-band tapes each recorded ~ 30 min. of data at 180 Mbits/sec, X-band tapes recorded 60 min. of data at 90 Mbits/sec, and were on average 73% utilized)

Data Acquisition: 222.4 hours total duration of mapping phase
99.2 hours C-band operation
90.6 hours X-band operation
8.6 Terabytes C-band data (=14,317 CDs)
3.7 Terabytes X-band data (=6101 CDs)
12.3 Terabytes total data (=20,418 CDs)
(Approx. equal to Library of Congress)

Data Played Back 104 C-band playbacks
During Flight 49 X-band playbacks

Energy used: 902.8 kWh (911 kWh planned)

Payload Weight: approximately 13,600 kg (approximately 29,000 lbs or 14.5 tons)

Mission Costs: $133M Mission Development Costs without Launch Delay
$8.2M Launch Delay Costs
$142M Total Mission Cost
$50M Launch Costs
$40M X-SAR Costs

Mission Objective:
To use C-band and X-band interferometric synthetic aperture radars (IFSARs) to acquire topographic data over 80% of Earth's land mass (between 60degN and 56degS) during an 11-day Shuttle mission. Produce digital topographic map products which meet Interferometric Terrain Height Data (ITHD)-2 specifications (30 m x 30 m spatial sampling with <=16 m absolute vertical height accuracy, <= 10 m relative vertical height accuracy and <=20 m absolute horizontal circular accuracy). All accuracies are quoted at the 90% level, consistent with National Map Accuracy Standards.

Mission Firsts:
  • Fixed baseline single-pass spaceborne interferometric SAR
  • Dual frequency (C-band and X-band) interferometric SAR
  • Largest rigid structure flown in space

Mast Information:
Mast Length 60 m 200 feet
Nominal Mast Diameter 1.12 m 44.12 in
Nominal Bay Width at Longerons 79.25 cm 31.20 in
Nominal Bay Length 69.75 cm 27.46 in
Number of Bays 87  
Canister Diameter (at largest ring) 1.36 m 53.5 in
Stack Height/Bay 1.59 cm 0.63 in
Canister Length 2.92 m 115 in
Mast Mass 290 kg 640 lb
Canister Mass 695 kg 1530 lb
Mast Material: longeron material is carbon fiber reinforced plastic (CFRP);
Diagonal materials include stainless steel and alpha titanium.
Ball joints are made from hardened stainless steel.
Mast Construction: AEC-Able Engineering Company, Inc. (ABLE), Goleta, California

Mission Sponsors:
  • National Geospatial-Intelligence Agency (NGA)
  • National Aeronautics and Space Administration (NASA)
  • German Aerospace Center (DLR, Deutsches Zentrum fur Luft- und Raumfart)
  • Italian Space Agency (ASI, Agenzia Spaziale Italiana)
Project Management:
  • Jet Propulsion Laboratory
Data Product Applications:
  • Scientific applications:
    • Geology, geophysics, earthquake research, volcan
    • monitoring
    • Hydrologic modeling
    • Co-registration of remotely acquired image data
  • Civilian applications:
    • Enhanced Ground Proximity Warning Systems for aircraft
    • Civil engineering, land use planning
    • Line of sight determination for communications (e.g. cell phones)
  • Military applications:
    • Flight simulators
    • Logistical planning, trafficability
    • Missile and weapons guidance systems
    • Battlefield management, tactics
  • Modifying and adding to SIR-C/X-SAR instruments flown successfully as Space Radar Laboratory Missions (SRL-1, April 1994; SRL-2 October 1994)
  • Partnership: Major new components provided by industry.
Mission Manifest:
  • STS-99 Shuttle Endeavour
  • SRTM was a single payload mission
  • Shuttle travelled tail forward at 7.5 km/sec (17,000 mph)
  • Attitude was rolled 59 deg from the bay-down orientation, placing the mast at 45 deg from vertical
  • Nominal altitude: 233 km (approximately126 nautical miles, 145 statute miles) with orbital adjustment once per day
  • 150 data acquisition orbits plus activation, on-orbit checkout and de-activation
  • 6-member crew to activate payload, deploy and stow mast, align inboard and outboard antennas, monitor payload flight systems, operate on-board computers & recorders, & handle contingencies
STS-99 Crew Commander: Kevin Kregel
Pilot: Dom Gorie
Mission Specialists: Janet Kavandi, Janice Voss, Mamoru Mohri (NASDA), Gerhard Thiele (ESA)

Significant Contractors:
  • AEC-ABLE Engineering, Goleta, CA (deployable mast & canister)
  • America Technology Consortium, Camarillo, CA, (motors and actuators)
  • Ball Telecommunication Products Division, Boulder, CO(outboard antenna)
  • Daimler-Benz Aerospace (Dornier Satellite Systems), Friedrischafen, Germany (X-band radar system)
  • Composite Optics Inc., San Diego, CA (composite outboard structure)
  • ENERTEC, France (onboard high rate recorders)
  • Lockheed Martin, Palo Alto, CA (star tracker)
  • Mission Space, La Canada, CA (command & telemetry systems)
  • JDS Uniphase Corporation, Chalfont, PA (calibration optical link)