Landsat 1 History

July 23, 1972 - January 6, 1978

Figure 1. Landsat 1

Participants

• NASA
• Department of the Interior (DOI) U.S. Geological Survey (USGS)
• Manufacturer: General Electric's (GE's) Space Division in Valley Forge, Pennsylvania
   

Launch

• Date: July 23, 1972
• Vehicle: Delta 900
• Launched by: NASA
• Site: Vandenberg Air Force Base, California
   

Spacecraft

• Weight: approximately 953 kg (2,100 lbs)
• Overall height: 3 m (10 ft)
• Diameter: 1.5 m (5 ft)
• Solar array paddles extend out to a total of 4 m (13 ft)
• 3-axis stabilized using 4 wheels to +/-0.7° attitude control
• Twin solar array paddles (single-axis articulation)
• S-Band and Very High Frequency (VHF) communications
• Hydrazine propulsion system with 3 thrusters
   

Communications

• Direct downlink from 2, 30 minute wide-band video tape recorders
• Data rate: 15 Mbps
• Quantization: 6 bit (64 levels)
   

Orbit

• Worldwide Reference System-1 (WRS-1) path/row system
• Sun-synchronous, near-polar orbit at an altitude of 917 km (570 mi)
• Inclined at 99.2°
• Circled the Earth every 103.34 minutes
• Completed 14 orbits per day
• Repeat cycle: 18 days
• Swath width: 185 km (115 mi)
• Equatorial crossing time: 9:30 a.m. +/- 15 minutes
• Swath overlap (or sidelap) varied from 14 percent at the Equator to a maximum of approximately 85 percent at 81° north or south latitude
   

Sensors

Return Beam Vidicon (RBV)

• Operated from July 23, 1972 to August 5, 1972, recording only 1692 images
• 80 meter-ground resolution
• Three cameras operating in the following spectral bands:
  
  • Band 1 Visible blue-green (475-575 nm)
  • Band 2 Visible orange-red (580-680 nm)
  • Band 3 Visible red to Near-Infrared (690-830 nm)
• Data: 3.5 MHz FM video
   

Multispectral Scanner (MSS)

• 80-meter ground resolution in four spectral bands:
  
  • Band 4 Visible green (0.5 to 0.6 µm)
  • Band 5 Visible red (0.6 to 0.7 µm)
  • Band 6 Near-Infrared (0.7 to 0.8 µm)
  • Band 7 Near-Infrared (0.8 to 1.1 µm)
• Six detectors for each spectral band provided six scan lines on each active scan
• Ground Sampling Interval (pixel size): 57 x 79 m
   

Other Characteristics

• Scene size: 170 km x 185 km (106 mi x 115 mi)
• Originally named ERTS-A (Earth Resources Technology Satellite); also known as ERTS-1 and Landsat-1
• Program renamed Landsat in 1975
• Design Life: Minimum of 1 year