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| USGS › Geography › Earth Resources Observation and Science (EROS) Center |
Landsat TM Image (San Diego, CA)
Beginning September 30 2008, the USGS will offer all users the Landsat 7 archive data at no charge using a standard data product recipe. The Landsat TM and Landsat MSS archive will also become available at no charge with a standard recipe in December 2008 and January 2009 respectively.
At those times, the current products listed below will no longer be available for ordering. Please view the Technical Announcement (PDF) for additional information.
The Landsat Thematic Mapper (TM) is a sensor carried onboard Landsats 4 and 5 and has acquired images of the Earth nearly continuously from July 1982 to the present, with a 16-day repeat cycle.
Landsat TM image data consist of seven spectral bands (band designations) with a spatial resolution of 30 meters for bands 1 to 5 and band 7. Spatial resolution for band 6 (thermal infrared) is 120 meters, but band 6 data are oversampled to 30 meter pixel size. Approximate scene size is 170 km north-south by 183 km east-west (106 mi by 114 mi).
The following levels of correction are available to the general public.
The distribution of Landsat 4-5 TM Terrain correction data is restricted to U. S. Government and its affiliated users. Please contact USGS EROS Customer Services if you have questions regarding this policy.
Update: As of May 11, 2006, all Level 1 Landsat TM products will have the Memory Effect (ME) correction algorithm applied at no additional cost. ME is an image artifact that appears as alternating lighter and darker stripes that are 16 pixels wide. ME has also been referred to as "banding" or "bright target recovery".
ME is typically seen in imagery from bands 1-4 over large areas, in areas with a significant transition in radiant intensity, such as a cloud/desert or snow/water boundary. The new Level 1 correction algorithm should significantly reduce or eliminate ME artifacts in TM imagery.
For all levels of correction, the following processing parameters are customer-defined:
| Processing Parameters | Available options |
|---|---|
| Map projection | UTM Space Oblique Mercator Albers Equal-Area other* |
| Horizontal datum | WGS84 NAD83 NAD27 other* |
| Resampling method | cubic convolution (CC) nearest neighbor (NN) other* |
| Image orientation | Map (north up) Path (satellite; not recommended for UTM projection) |
| Pixel size | 30 meters 28.5 meters other* |
| Formats | NDF (NLAPS Data Format) GeoTIFF*** |
| Media Type | CD DVD FTP |
| Delivery Time | FTP: 1 to 3 days Media: 5 to 10 days The above are average delivery times and are not guaranteed. The actual delivery time may vary, depending on the workload at the time an order is placed. Delivery time may also be longer if shipping to a location outside the United States. |
*Other options may be available upon request.
***GeoTIFF format includes a Work Order (.WO.txt) file that holds the metadata details of each TM scene.
| Level of Correction | Price |
|---|---|
| Systematic Correction | $425 per scene |
| Precision Correction | $550 per scene |
| Terrain Correction | $625 per scene |
A bulk discount of 20 percent off the standard product price will be applied to orders containing 25 or more single Landsat scenes (any combination of MSS, TM, and ETM+ SLC-on are allowed). No discounts are available for L7 ETM+ SLC-off or ETM+ Gap-filled products.
Effective April 2, 2007, updates to the radiometric calibration of Landsat 5 (L5) Thematic Mapper (TM) data processed and distributed by the U.S. Geographical Survey (USGS) Center for Earth Resources Observation and Science (EROS) will be available. The full implementation of these processing changes will lead to an improved Landsat 5 TM data product that will be more comparable to Landsat 7 Enhanced Thematic Mapper Plus (ETM+) radiometry, and will prvide the basis for continued long-term studies of the Earth's land surfaces.
Although this calibration update applies to all archived and future L5 TM data, the principal improvements in the calibration are for data acquired during the first eight years of the mission (1984-1991), where the change in the instrument gain values is as much as 15 percent. Additionally, the radiometric scaling coefficients for Bands 1 and 2 have also been changed for approximately the first eight years of the mission. Users will need to apply these new coefficients to convert the calibrated date product digital numbers to radiance. The scaling coefficients for the other bands have not changed.
The lifetime gain model that was implemented on May 5, 2003 for the reflective bands (1-5,7) will be replaced by a new lifetime radiometric calibration curve derived from the instrument's response to pseudo-invariant desert sites and from cross-calibration with Landsat 7 ETM+. To access the current Look-up Table, please visit http://landsat.usgs.gov/technical_details/calibration_files/l5_lut.php
All Landsat TM scenes in the USGS archive can be searched by geographic location using Earth Explorer or the USGS Global Visualization Viewer (GloVis). Only scenes with browse capability can be searched and ordered on GloVis.
All Landsat 5 TM data are referenced to WRS-2, the Worldwide Reference System of paths and rows.
New TM scenes generally become available for search and order within 6 to 24 hours after data acquisition. To view real-time acquisitions of Landsat over the United States, please visit EarthNow!
Some Landsat 5 TM scenes of areas outside the United States are not archived or distributed by USGS EROS. These scenes may be available from International Ground Stations (IGSs). IGS data are not products of USGS EROS and therefore prices, available formats, and processing options may vary according to the data provider.
Landsat TM images should always be previewed prior to purchase. Browse images of available scenes may be viewed by searching on Earth Explorer or GloVis.
Each Landsat TM browse image is a resampled JPEG of the actual scene data. The browse image is displayed as a 5,4,3 (RGB) composite with a standardized 2% linear stretch applied.
Landsat TM product samples are available for download at the Landsat Sample Products Web page.
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