Landsat: The Longest Running Earth Imaging Program

With satellites in orbit since 1972, the Landsat program is the longest running Earth observation program. The Earth imaging program, originally created to investigate Earth’s landmass, has contributed to a wide range of subjects, from the natural sciences to the social sciences.

Since the first satellite imagery of Landsat 1 in 1972, several Landsat satellites have been launched with the ability to take increasingly detailed images of our world.

These two images show an increase in image resolution and sensor data quality on the Landsat Silicon Valley imagery located in Northern California. The image on the left is a Landsat 1 image obtained in 1972 and the image on the left is a Landsat 8 image obtained in 2016.

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

Landsat Satellite Launch Timeline

Landsat launch timeline. Graphics: Caitlin Dempsey.

Landsat 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 year, Landsat 1 lasted six years before being decommissioned on January 6, 1978.

Landsat 1 orbits Earth at 917 km (570 miles) in a near-pole-synchronized orbit with the sun. 14 times a day, Landsat 1 circles the Earth.

Landsat 1 captured a false color satellite image of Fort Worth Texas on July 25, 1972. Red areas are vegetation and gray and white areas are urban areas.

Fun fact: 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 significant because it showed Earth-observing researchers how little land satellite technology at the time could capture it.

The discovery of the unexplored Canadian island extends the country’s borders offshore and increases its territorial waters to 68 square kilometers. The island was named Landsat Island after the origin of its discovery.

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

Landsat 2

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

Landsat 2 orbits Earth at 900 km (559 mi) in a sun-synchronous near-pole orbit (99.2 degree tilt). Like Landsat 1, Landsat 2 orbits the earth every 103 minutes for a total of 14 times a day.

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

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

Landsat 3

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

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

Landsat 3 orbits Earth at 917 km (570 mi) in a sun-synchronous near-pole orbit (99.2 degree tilt) 14 times a day.

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

Northern California’s first light image of Landsat 3. Image: USGS, public domain.

Landsat 4

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

Landsat 4 orbits Earth in an orbit near the poles that is in sync with the sun (inclination of 98.2 degrees). Landsat 4 has a lower orbit than the first three satellites at an altitude of 705 km (438 mi).

The improved Landsat 4 spatial resolution is 30 meters and the satellite data collection includes thermal bands. The new Thematic Mapper sensor on Landsat 4 enables the depiction of data as natural color for the first time.

On July 25, 1982, the first light image from Landsat 4 captured the eastern half of Lake Erie, Toledo, Detroit, and Windsor.

First Light Image of Landsat 4 west of Lake Erie, July 25, 1982. Image: USGS, public domain.

Landsat 5

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

Landsat 5 orbits Earth at 705 km (438 mi) in a near-pole-synchronized orbit with the sun (98.2 degrees tilt). The satellites circle the earth every 99 minutes for a total of fourteen orbits a day.

Like Landsat 4, Landsat 5 carries a Multispectral Scanner (MSS) and Thematic Mapper (TM) instrument and produces satellite images with a spatial resolution of 30 meters. When the TM sensor failed in 2011, the MSS sensor continued to collect satellite data into 2013.

The first light image of Landsat 5 was obtained on March 6, 1984 and shows Lake Superior, northern Minnesota, and the Wisconsin Apostle Islands.

False color composite satellite image using near infrared, red and green bands for Lake Superior, northern Minnesota, and the Wisconsin 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 was the only satellite in the Landsat program to fail.

Landsat 7

Landsat 7 was launched on April 15, 1999. Landsat 7 improvements over previous satellites in the program include a thermal infrared channel feature with a fourfold increase in spatial resolution via Thematic Mapper(TM), onboard full aperture solar calibrator, panchromatic band with 15 spatial resolution meters, and a five percent absolute radiometric calibration.

Landsat 7 orbits Earth at 705 km (438 miles) in a near-pole-synchronous orbit with the sun (98.2 degrees tilt) every 99 minutes.

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

Landsat 7-color infrared image of Southeastern Dakota obtained on April 18, 1999. The Missouri River flows from the lower right of the image, where the Fort Randall Dam produces Lake Francis Case, to the center 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 Thermal Infrared Sensor (TIRS) instruments.

The Landsat 8 imagery has a panchromatic spatial resolution of 15 meters and a multispectral resolution of 30 meters over a swath of 185 km (115 mi).

Landsat 8 orbits Earth in a solar synchronous near-pole orbit (98.2 degrees tilt) at an altitude of 705 km (438 mi). Satellites circle the earth every 99 minutes.

Natural 8 color Landsat scene obtained on March 18, 2013. The scene shows the area where the Great Plains meet the Rocky Mountain Front in Wyoming and Colorado. Image: USGS/NASA Earth Observatory, public domain.

Landsat 9

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

Landsat 9 acquired the first few light images:

First light image of Landsat 9 Nepal, 31 October 2021. Image; USGS, public domain.

Reference

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

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

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