Landsat 7

The Landsat 7 Mission was decommissioned on June 4, 2025.  During its 26 year mission, the satellite traveled more than 3.8 million miles. The ETM+ sensor collected over 3.3 million images that were processed into products that added over 3 petabytes of data to the USGS archive. Landsat 7 has been cited in over 1,400 policy documents. Click on each image below to see the impact Landsat 7 had on Earth observation. 

Landsat 7 Satellite Orbit Facts *

* These facts were applicable while the satellite was in nominal operations (April 1999 to May 2022) and are provided here as reference only. 

• Orbits the Earth at 705 km (438 mi) in a sun-synchronous, near-polar orbit (98.2 degrees inclination)
• Circles the Earth every 99 minutes
• Has a 16-day repeat cycle with an equatorial crossing time: 10:00 a.m. (+/- 15 minutes)
• Acquired on the Worldwide Reference System-2 (WRS-2) path/row system, with swath overlap (or sidelap) varying from 7 percent at the Equator to a maximum of approximately 85 percent at extreme latitudes

Landsat 7 Spacecraft Facts

• Power provided by a single Sun-tracking solar array and two 50 Ampere-Hour (AHr), Nickel Cadmium (NiCd) batteries
• Attitude control provided through four reaction wheels (pitch, yaw, roll, and skew); three 2-channel gyros with celestial drift updating; a static Earth sensor; a 1750 processor; and torque rods and magnetometers for momentum uploading
• Orbit control and backup momentum unloading provided through a blow-down monopropellant hydrazine system with a single tank containing 270 pounds of hydrazine, associated plumbing, and twelve 1-pound-thrust jets
• Weight: approx. 4,800 lbs (2,200 kg)
• Length: 4.3 m (14 ft)
• Diameter: 2.8 m (9 ft)
• Direct Downlink with Solid State Recorders (SSR)
• Data rate: 150 Mbps

Landsat 7 Enhanced Thematic Mapper Plus (ETM+) Instrument

Landsat 7 carried the Enhanced Thematic Mapper Plus (ETM+) sensor, an improved version of the Thematic Mapper instruments that were onboard Landsat 4 and Landsat 5. Landsat 7 products were delivered as 8-bit images with 256 grey levels. Descriptions of Landsat 7 band designations and comparisons of all Landsat sensors are available.

• The ETM+ contains eight spectral bands, including a pan and thermal band:
  • Band 1 Blue (0.45 - 0.52 µm) 30 m
  • Band 2 Green (0.52 - 0.60 µm) 30 m
  • Band 3 Red (0.63 - 0.69 µm) 30 m
  • Band 4 Near-Infrared (0.77 - 0.90 µm) 30 m
  • Band 5 Short-wave Infrared (1.55 - 1.75 µm) 30 m
  • Band 6 Thermal (10.40 - 12.50 µm) 60 m Low Gain / High Gain
  • Band 7 Mid-Infrared (2.08 - 2.35 µm) 30 m
  • Band 8 Panchromatic (PAN) (0.52 - 0.90 µm) 15 m
• Ground Sampling Interval (pixel size): 30 m reflective, 60 m thermal
• Added the Band 6 Low and High gain 60 m thermal bands
• On-board calibration was added to Landsat 7: a Full Aperture Solar Calibrator (FASC) and a Partial Aperture Solar Calibrator (PASC), in addition to the 2 calibration lamps

Landsat 7 Products

Landsat 7 products are consistent with all Landsat standard data products, using the specifications described on the Landsat Processing Details page.

Landsat 7 Scan Line Corrector (SLC) Failure

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On May 31, 2003, the Scan Line Corrector (SLC), which compensated for the forward motion of the satellite, failed. Subsequent efforts to recover the SLC were not successful, and the failure was permanent. Without an operating SLC, the sensor’s line of sight traced a zig-zag pattern along the satellite ground track.

As a result, the imaged area was duplicated, with a width that increased toward the edge of the scene.  When the Level-1 data were processed, the duplicated areas were removed, leaving gaps. Even though there was data loss, 78 percent of the scene's pixels still remain after the duplicated areas were removed, and these data are still some of the most geometrically and radiometrically accurate of all civilian satellite data in the world.

Band-specific gap mask files are included with every Landsat 7 Scan Line Corrector (SLC)-off Level-1 data product. These ancillary data identify the location of all pixels affected by the original data gaps in the primary SLC-off scene. This webpage provides more details about these files: What are Landsat 7 SLC-off Gap Mask files. 

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A number of papers were written about the Landsat 7 Scan Line Corrector: 

• Preliminary Assessment of the Value of Landsat 7 ETM+ Data Following Scan-Line Correction Malfunction. ( A summary of analysis done by the 1996-2001 Landsat Science Team)
• Landsat 7 Scan Line Corrector Processing Algorithm Theoretical Basis
• Landsat 7 SLC Gap-Filled Products Phase One Methodology
• Landsat 7 SLC-off Gap-Filled Products Phase Two Methodology
• Evaluation of L7 Gap-filled SLC-OFF Imagery for Burn Severity Mapping

Landsat 7 End of Mission Activities 

June 4, 2025: Mission Decommissioning

After 26 years in orbit, the satellite received its final transmission on June 4, 2025. The Landsat 7 science mission, which focused on collecting imagery data of Earth’s land, inland waters, and coastal waters, spanned 25 years. 

• June 4, 2025 - A Final Farewell to Landsat 7
• June 4, 2025 - End of an Era: Landsat 7 Decommissioned after 25 Years of Earth Observation 

 May 5, 2022 - January 19, 2024: Extended Science Mission

Landsat 7 imaging resumed on May 5, 2022, at a lower orbit of 697 km after a series of maneuvers in early April lowered the satellite out of the standard 705km WRS-2 orbit. The USGS elected to continue science data acquisition from the Enhanced Thematic Mapper Plus (ETM+) to assess the utility of imagery collected at the new lower orbit and earlier equatorial crossing time. 

Since being lowered in orbit, the satellite has continued to drift within its orbit, exposing it to periods of full sunlight and earlier imaging times, impacting imaging opportunities and the ability to process valid science data. In January 2024, the satellite’s moved into full sunlight, which causes issues with the batteries. To retain the health and safety of the batteries, science imaging was suspended on January 19, 2024. 

The Landsat 7 Extended Science Mission webpage describes the properties of the data, and activities done by Calibration/Validation and science teams to ensure the quality of the data remains nominal. 

Note: The Product Identifier for each scene contains the acquisition date, so Landsat 7 scenes collected at the lower orbit can be identified by searching for Landsat 7 data acquired May 4, 2022 - January 19, 2024. 

April 6, 2022: Nominal Science Mission Ends

On April 6, 2022, the ETM+ sensor was placed into “stand-by” mode as a series of spacecraft burns were performed throughout the month of April to lower the satellite’s orbit by 8 kilometers (see illustration below). After entering the lower orbit, the Landsat 7 satellite will be available for servicing by NASA's On-Orbit Servicing, Assembly, and Manufacturing-1 (OSAM-1) mission. OSAM-1 will provide Landsat 7 with the needed fuel for a successful decommissioning. 

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February 7, 2017: Final Inclination Maneuver

On February 7, 2017, the twentieth and final inclination (Delta-I) maneuver of Landsat 7 took place. (Delta-I maneuvers keep the spacecraft in the correct orbital position to ensure it maintains its 10:00 am ± 15 minutes mean local time (MLT) equatorial crossing.)  Landsat 7 reached its peak outermost inclination boundary of 10:14:58 MLT on August 11, 2017. The chart below illustrates the inclination trend from June 2014 to June 2026. By the end of 2021, the satellite had a MLT of 9:00 am. This 2021 publication describes the research conducted into the science capability of Landsat 7 ETM+ data, while the satellite is drifting in orbit. 

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Landsat 7 Data User's Handbook