Landsat: Longest Running Earth Imagery Program

With satellites in orbit since 1972, the Landsat program longest running Earth observation program. The Earth imaging program, which was initially created to investigate the landmasses of Earth, has since contributed to a variety of subjects, spanning from the natural to the social sciences.

Since the first satellite images from Landsat 1 in 1972multiple Landsat satellites have been launched with the ability to take increasingly detailed pictures of our world.

These two images show the improvement in image resolution and data sensor quality in Landsat imagery of the Silicon Valley which is located in Northern California. The image on the left is Landsat 1 imagery acquired in 1972 and the image on the left is Landsat 8 imagery acquired in 2016.

Landsat 1 satellite imagery (left) from 1972 and Landsat 8 satellite imagery (right) from 2016 of the Silicon Valley in Northern California.

Timeline of Landsat Satellite Launches

Timeline with deep red for the numbers and bars showing length of Landsat satellite missions against a cream background.
Timeline of Landsat launches. Graph: Caitlin Dempsey.

land satellite 1

The first Landsat satellite was launched on July 23, 1972 and was originally named Earth Resources Technology Satellite (ERTS-1). Originally designed to be in space for one yearLandsat 1 lasted six years before it was decommissioned on January 6, 1978.

Landsat 1 orbited the Earth at 917 km (570 mi) in a sun-synchronous, near-polar orbit. 14 times a day, Landsat 1 circled the Earth.

Landsat 1 captured this false-color satellite imager of Fort Worth Texas on July 25, 1972. The red areas are vegetation and grays and whites are urban areas.

Fun fact: An analysis of Landsat 1 images led to the discovery of a small island off the coast of Labrador, Canada. The discovery of the small rocky island was important as it demonstrated to Earth observation researchers how small of a land mass satellite technology at the time could capture.

The discovery of this unexplored Canadian island extended the country’s border offshore and increased its territorial waters by 68 square kilometers. the island was named Landsat Island after the origins of its discovery.

False-color satellite image of the Fort Worth, Texas area. Image: Landsat 1, July 25, 1972, USGS, public domain.

land satellite 2

On January 22, 1975, Landsat 2 was launched into orbit as Earth Resource Technology Satellite B (ERTS-B) before being renamed. As with Landsat 1, Landsat 2 had a one-year life design but lasted seven years before being decommissioned on July 27, 1983.

Landsat 2 orbited the Earth at 900 km (559 mi) in a sun-synchronous, near-polar orbit (99.2 degrees inclination). As with Landsat 1, Landsat 2 orbited the Earth every 103 minutes for a total of 14 times a day.

The first light image from Landsat 2 was captured over Alberta, Canada on January 24, 1975.

Natural color satellite image of Alberta, Canada.
Natural color satellite image over Alberta, Canada. Image: Landsat 2, January 24, 1975, USGS, public domain.

Landsat 3

Developed to extend the length of Earth observation time, Landsat 3 was launched on March 5, 1978 and was decommissioned five years later on September 7, 1983.

Landsat 3 improved on the spatial resolution of the first two Landsat with its Return Beam Vidicon (RBV) sensor carrying a resolution of 40 meters compared to 80 meters. Landsat 3 also carried a thermal infrared band on its Multispectral Scanner System (MSS) sensor but that failed shortly after launch.

Landsat 3 orbited the Earth at 917 km (570 mi) in a sun-synchronous, near-polar orbit (99.2 degrees inclination) 14 times a day.

On March 7, 1978, Landsat 3 captured its first image over the Silicon Valley in Northern California.

Satellite image that is mostly green of Northern California.
Landsat 3 first light image of Northern California. Image: USGS, public domain.

land satellite 4

Landsat 4 was launched on July 16, 1982 and the satellite collected data until December 1993 but wasn’t decommissioned until 2001.

Landsat 4 orbited the Earth in a sun-synchronous, near-polar orbit (98.2 degrees inclination). Landsat 4 had a lower orbit than the first three satellites with an altitude of 705 km (438 mi).

Landsat 4’s improved spatial resolution was 30 meters and the satellite’s data collection included a thermal band. The new Thematic Mapper sensor onboard Landsat 4 allowed for the first time the depiction of data as natural color.

On July 25, 1982, the first light image from Landsat 4 captured eastern Lake ErieToledo, Detroit, and Windsor.

Satellite image of eastern Lake Erie with the blue edge of the lake and the surrounding green and gray urbanized areas.
Landsat 4 first light image over western Lake Erie, July 25, 1982. Image: USGS, public domain.

Landsat 5

Landsat 5 has been the longest Earth Observation satellite, having orbited the Earth for almost 29 years from March 1, 1984 to June 5, 2013. Landsat 5 holds the Guinness World Record for ‘Longest Operating Earth Observation Satellite.’ The original lifespan of Landsat 5 was three years.

Landsat 5 orbited the Earth at 705 km (438 mi) in a sun-synchronous, near-polar orbit (98.2 degrees inclination). The satellite circled the Earth every 99 minutes for a total of fourteen orbits a day.

As with Landsat 4, Landsat 5 carried both the the Multispectral Scanner (MSS) and the Thematic Mapper (TM) instruments and produced satellite imagery with a spatial resolution of 30 meters. When the TM sensor failed in 2011, the MSS sensor continued to collect satellite data until 2013.

The first light image from Landsat 5 was acquired on March 6, 1984 and shows Lake Superiornorthern Minnesota, and the Wisconsin’s Apostle Islands.

Satellite image of the northern Wisconsin area.
False color composite satellite image using the near infrared, red and green bands for Lake Superior, northern Minnesota, and the Wisconsin’s Apostle Islands. Image: Landsat 5, March 6, 1984, USGS, public domain.

Landsat 6

Landsat 6 was launched on October 5, 1993 and failed to reach orbit. Landsat 6 is the only satellite in the Landsat program that failed.

Landsat 7

Landsat 7 was launched on April 15, 1999. Improvements to Landsat 7 over the previous satellites in the program included feature a thermal infrared channel with a four-fold increase in spatial resolution over Thematic Mapper (TM), an onboard full aperture solar calibrator, a panchromatic band with a 15-meter spatial resolution, and five percent absolute radiometric calibration.

Landsat 7 orbits the Earth at 705 km (438 mi) in a sun-synchronous, near-polar orbit (98.2 degrees inclination) every 99 minutes.

Data from the Landsat 7 was made free to the public in October of 2008. About four months later, the government expanded the free data option to the entire Landsat program.

Color infrared image of Southeast South Dakota.
Landsat 7 color infrared image of Southeast South Dakota acquired on April 18, 1999. The Missouri River flows from the lower right of the picture, where the Fort Randall Dam generates Lake Francis Case, to the middle left of the satellite image. Image: USGS, public domain.

Landsat 8

Landsat 8 was launched on February 11, 2013. Landsat 8 carries the Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS) instruments.

Landsat 8 images have 15-meter panchromatic and 30-meter multi-spectral spatial resolutions along a 185 km (115 mi) swath.

Landsat 8 orbits the Earth in a sun-synchronous, near-polar orbit (98.2 degrees inclination) with an altitude of 705 km (438 mi). The satellite circles the Earth every 99 minutes.

Natural color Landsat scene showing a brown landscape covered by small clouds that dot the landscape.
Natural color Landsat 8 scene was acquired on March 18, 2013. The scene shows the area where the Great Plains meet the Front Range of the Rocky Mountains in Wyoming and Colorado. Image: USGS/NASA’s Earth Observatory, public domain.

Landsat 9

Landsat 9 is the latest satellite in the Landsat mission to be launched. Landsat 9 what launched on September 27, 2021 and carries the Operational Land Imager 2 (OLI-2) and the Thermal Infrared Sensor 2 (TIRS-2).

Landsat 9 acquired several first light images:

Satellite image of Nepal showing snowy peaks and tan and dark green landscapes.
Landsat 9 first light image of Nepal, October 31, 2021. Image; USGS, public domain.

References

Gray, E. (2013, March 21). A closer look at LDCM’s first scene. NASA. https://www.nasa.gov/mission_pages/landsat/news/first-images-feature.html

Landsat missions. (nd). USGS.gov. https://www.usgs.gov/landsat-missions

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