Editing Landsat program (section)

{{Short description|American network of Earth-observing satellites for international research purposes}}
{{Use American English|date=March 2021}}
{{Use dmy dates|date=March 2021}}
[[Image:Landsat7photo.jpg|thumb|upright|right|[[Landsat 7]], launched in 1999, is the 7th of 9 satellites in the Landsat program.]]
{{multipleimage
| direction         = horizontal
| image1            = Large Kolkata Landsat.jpg
| caption1          = A [[false-color]] satellite image of [[Kolkata]], India, from [[Landsat 7]] in 2004, showing rivers, vegetated areas, and developed areas
| image2            = Island of Hawai'i - Landsat mosaic.jpg
| caption2          = A land cover map of the big island of [[Hawaii (island)|Hawaii]] using 1999–2001 data from [[Landsat 7]], showing black lava flows from [[Mauna Loa]], grayish dormant [[Mauna Kea]], a plume of smoke from active [[Kilauea]], dark green tropical forests, and light green agricultural areas
}}

The '''Landsat program''' is the longest-running enterprise for acquisition of [[satellite imagery]] of [[Earth]]. It is a joint [[National Aeronautics and Space Administration|NASA]] / [[United States Geological Survey|USGS]] program. On 23 July 1972, the [[Landsat 1|Earth Resources Technology Satellite]] was launched. This was eventually renamed to Landsat 1 in 1975.<ref>{{cite book |last=Short|first=N.M.|title=The LANDSAT Tutorial Workbook: Basics of Satellite Remote Sensing|id=1078|date=1982 |location=Washington DC |publisher=NASA|hdl=2060/19830002188}} {{PD-notice}}</ref> The most recent, [[Landsat 9]], was launched on 27 September 2021.

The instruments on the Landsat satellites have acquired millions of images. The images, archived in the [[United States]] and at Landsat receiving stations around the world, are a unique resource for global change research and applications in [[agriculture]], [[cartography]], [[geology]], [[forestry]], [[regional planning]], [[surveillance]] and [[education]], and can be viewed through the U.S. Geological Survey (USGS) "EarthExplorer" website. [[Landsat 7]] data has eight [[spectral bands]] with [[Image resolution#Spatial resolution|spatial resolutions]] ranging from {{cvt|15|to|60|m}}; the [[temporal resolution]] is 16 days.<ref>[http://landsat.gsfc.nasa.gov/about/L7_td.html The Landsat Program – Technical Details] {{webarchive|url=https://web.archive.org/web/20100501135128/http://landsat.gsfc.nasa.gov/about/L7_td.html |publisher=NASA|date=2010-05-01}} {{PD-notice}}</ref> Landsat images are usually divided into scenes for easy downloading. Each Landsat scene is about 115 miles long and 115 miles wide (or 100 [[nautical miles]] long and 100 nautical miles wide, or 185 kilometers long and 185 kilometers wide).