Frequently Asked Questions
Mapping, Remote Sensing, and Geospatial Data
The USGS provides the mapping and digital geospatial foundation for the Nation.
The Worldwide Reference System (WRS) is a global system that catalogs Landsat data by Path and Row numbers. Landsat satellites 1, 2 and 3 followed WRS-1, and Landsat satellites 4,5,7, and 8 follow WRS-2.
Learn more:
Landsat Path Row Shapefiles and KML Files
The Worldwide Reference System (NASA)
There are several Landsat data products that are useful for science applications and land use/land change studies:
Landsat Collections Level 1 - Ensures that the data in the Landsat Level-1 archive are consistent in processing and data quality to support time-series analyses and data stacking. Each Level-1 data product includes individual spectral...
Definitive Ephemeris is used for geometrically correcting Landsat 7 data and providing improved accuracy over predicted ephemeris.
Learn more (and download DE files): Landsat Definitive Ephemeris
Landsat Response Linearization Look Up Tables (RLUT) are additional files that accompany Calibration Parameter Files (CPFs) and contain a mapping lookup table to linearize the output of the Landsat 8 Operational Land Imager (OLI) detectors.
Learn more (and download RLUT files): Landsat Response Linearization Look Up Tables
Landsat Bias Parameter Files (BPFs) supply radiometric correction parameters that are applied during Level-1 processing of Landsat data.
Learn more (and search for BPF files): Landsat Bias Parameter
Landsat Calibration Parameter Files (CPFs) provide radiometric and geometric coefficients needed for processing of raw, uncorrected Landsat image data into Level-1 data products. Over 15,000 coefficients are issued to span distinct timeframes and are updated with improved calibration coefficients. CPFs are often updated with improved coefficients...
The C Function of Mask (CFMask) algorithm populates cloud, cloud confidence, cloud shadow, and snow/ice pixels in the processing of Landsat Collections Level-1 data products, with the results represented as bit-mapped values within the Landsat Collection 1 Level-1 Quality Assessment (QA) Band. CFMask derives from the Function of Mask (FMask), an...
The Landsat Collection 1 Level-1 product metadata (MTL.txt) file includes a SATURATION_BAND_ x”parameter for each Landsat band. This field indicates the presence of radiometric saturation for each bandin every Landsat scene.
Learn more: Landsat Collections Level-1 Saturation Bits Parameter
The Landsat Collection 1 Angle Coefficient file provides sensor viewing angle model coefficients that can be used to create angle bands, and allows users to compute the solar and sensor viewing angles on a per-pixel basis.
Learn more: Solar Illumination and Sensor Viewing Angle Coefficient Files
The Landsat 7 SLC-off artifact does not change how the data are placed into Landsat Collection tiers, as tier classifications are determined by the radiometric and geometric accuracy of each scene.
Learn more:
Landsat Collections
Landsat Data Access
Landsat Level-1 data can be rescaled to the top of atmosphere (TOA) reflectance and/or radiance using radiometric rescaling coefficients provided in the metadata file (MTL.txt) that is delivered with the Landsat Level-1 product. The MTL file also contains the thermal constants needed to convert thermal band data to TOA brightness temperature (BT...
The historical Landsat Level-1 Scene ID is in the EarthExplorer metadata. After entering a search using the historical Scene ID, the Landsat Level-1 Collection 1 Product Identifier will be returned in the search results. The results can be exported from EarthExplorer in a variety of formats for metadata parsing.
We also encourage use of the Bulk...