Landsat Missions
Landsat Missions
The Landsat 8 satellite images the entire Earth every 16 days in an 8-day offset from Landsat 7. Data collected by the instruments onboard the satellite are available to download at no charge from EarthExplorer, GloVis, or the LandsatLook Viewer within 24 hours of acquisition.
Landsat 8 carries two push-broom instruments: The Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS).
The spectral bands of the OLI sensor provides enhancement from prior Landsat instruments, with the addition of two additional spectral bands: a deep blue visible channel (band 1) specifically designed for water resources and coastal zone investigation, and a new shortwave infrared channel (band 9) for the detection of cirrus clouds.*
The TIRS instrument collects two spectral bands for the wavelength covered by a single band on the previous TM and ETM+ sensors. Descriptions of the band designations for all Landsat sensors, and information about the comparisons between Landsat 8 and previous bands are also available.
These sensors both provide improved signal-to-noise (SNR) radiometric performance quantized over a 12-bit dynamic range. (This translates into 4096 potential grey levels in an image compared with only 256 grey levels in previous 8-bit instruments.) Improved signal to noise performance enable better characterization of land cover state and condition. Products are delivered as 16-bit images (scaled to 55,000 grey levels).
A Quality Assessment band is also included with each Landsat 8 data product. This band allows users to apply per pixel filters to the Landsat 8 Operational Land Imager (OLI)-only and Landsat 8 OLI/Thermal Infrared Sensor (OLI/TIRS)-combined data products.
Landsat 8 data products are consistent with other Landsat standard Level-1 data products, using specifications described on the Landsat Processing Details page.
Nearly 10,000 scenes were acquired by the Operational Land Imager (OLI) and/or Thermal Infrared Sensor (TIRS) sensors after launch (February 11, 2013) through April 10, 2013, when the satellite achieved operational orbit (WRS-2). The earliest images are TIRS data only. These data are also visible and can be downloaded from EarthExplorer or GloVis.
While these data meet the quality standards and have the same geometric precision as data acquired on and after April 11, 2013, the geographic extents of each scene may differ.
Most data will be processed to the highest level possible, however there may be some differences in the spatial resolution of the early TIRS images due to telescope temperature changes, but they should be within +/- 1 percent.
The Landsat 8 Data User's Handbook provides information about the Landsat 8 data products.
Information is available for converting Landsat 8 Level-1 data to radiance, reflectance and top of atmosphere brightness temperature.
Images of important areas in the development of Landsat 8 are available.
Landsat 8/ LDCM’s Underfly with Landsat 7
*Gao, B.C. and Kaufman, Y.J. 1995. Selection of the 1.375 micrometer MODIS Channel for Remote Sensing of Cirrus Clouds and Stratospheric Aerosols from Space, Journal of the Atmospheric Sciences, 52 (23), p.4231-4237.
Landsat represents the world's longest continuously acquired collection of space-based moderate-resolution land remote sensing data. Four decades of imagery provides a unique resource for those who work in agriculture, geology, forestry, regional planning, education, mapping, and global change research. Landsat images are also invaluable for emergency response and disaster relief.
U.S. Department of the Interior |
U.S. Geological Survey
URL: https://landsat.usgs.gov
Page Contact Information: Ask Landsat
Page Last Modified: 10/18/18 11:39 am
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