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Landsat 9: Continuing 50 Years of Eyes on our Changing Planet

illustration of the LANDSAT 9 spacecraft in Earth's orbit

What would you do with 50 years of Earth observations?

With 9 million images of our home planet’s landscapes and coastlines seen from space, all for free at your fingertips?

Mosaic of images taken by Landsat missions
Landsat imagery courtesy of NASA Goddard Space Flight Center and U.S. Geological Survey

The Landsat mission asks just that.

Since 1972, this partnership between NASA and the U.S. Geological Survey has continuously had satellites in orbit, looking back at Earth – and it continues with this year’s Landsat 9 launch.

Decades of Observation

Over the decades, Landsat has shown us:

Cities expanding into the desert (1972-1982)

(1972-1982) The spreading sprawl of Las Vegas, as seen in false-color images with parks and lawns in red.

Rivers and deltas changing course (1984-1991)

(1984-1991) Sediments flowing down the Atchafalaya River created new deltas in the Mississippi Basin.

Glaciers melting (1995-2002)

(1995-2002) As the climate warms, Landsat captures the retreat of Columbia Glacier in Alaska.

Reservoirs drying up in droughts (2002-2007)

(2002-2007) Lake Powell, along the Colorado River, is an essential source of water for cities and irrigation.

Farmers changing what they grow (2012-2020)

(2012-2020) Landsat data help the USDA track crops field by field – including almonds (in teal).

Data in Action

Landsat satellites give us a global perspective of how Earth is changing. That change could be due to natural causes like earthquakes, or due to human-caused drivers like greenhouse gas emissions that lead to warming temperatures on a global scale.

The satellite technology improves through the years, but the mission stays the same: monitor Earth’s land and coastal regions to help people manage natural resources. A recent USGS study found that in 2017 alone, having free and available Landsat data resulted in more than $3.4 billion in economic benefits to society.

Generations have used Landsat data to tackle problems crucial to everyday life on our planet.


In wildfire-prone California, Landsat data provides crucial information about the health of a forest. If a beetle infestation or drought kills trees, it shows up in Landsat images and tells us an area could be more at risk of a fire.

When a wildfire burns, Landsat images in natural color capture plumes of smoke. The satellite also has instruments that let us peer through the smoke and clouds to outline the extent of a burning or smoldering fire.

satellite view of an active fire near Paradise, California
Joshua Stevens, NASA Earth Observatory/Landsat

Landsat’s job isn’t over after the flames die down. The satellite helps direct recovery experts to the most damaged sites for replanting and landslide-prevention efforts. A recent study estimated Landsat data saves federal agencies in the United States about $7.7 million annually in post-fire recovery efforts by identifying these restoration sites.


From its orbit 400 miles above Earth, Landsat can also help us identify lakes and reservoirs struck by potentially harmful algal blooms. These greenish blooms are swirls of microscopic organisms, which can release toxins that sicken people and pets.

satellite view of algal blooms in a lake in Utah

Scientists are developing computer programs that would use Landsat and other satellite data to automatically warn lake recreation managers when blooms pop up – allowing them to test the waters and warn swimmers, boaters and picnickers before the little organisms become a big problem. Landsat 9 will be even better at distinguishing details of scenes that are really dark, like the deep blues and greens of these lakes.


Landsat also helps scientists study water in its frozen form – vast ice sheets in Antarctica, Arctic sea ice, and glaciers worldwide, including in Greenland.

Glaciologists can identify cracks and ridges in the glacier. By tracking them over time, they can see how fast the ice is moving – and get a better handle on the impacts of warming global temperatures on glaciers and on sea level rise.

satellite view showing a Greenland glacier's movement
NASA Goddard's Scientific Visualization Studio/Cindy Starr, data visualizer

Congo and Brazil

Scientists frequently combine Landsat data with other remote-sensing data, to give us a fuller portrait of Earth’s terrain. Scientists who wanted to map the healthiest tropical forests – showing not just the location of forests but the height of trees, combined Landsat data with observations from a NASA instrument that uses lasers to measure the height of trees.

Image showing a map of tree height in Congo

They’re hoping to use this tool in places like Congo and Brazil to focus conservation efforts on key forests.


Since the early days of the Landsat program, researchers and conservation groups have been tracking deforestation in the Amazon. There, they can see changes in the patterns of deforestation – from individual ranchers cutting down and burning smaller parcels of land to graze cattle, to the rise of large-scale industrial ranching and soybean farms.

Credit: NASA


The first Landsat was designed with agricultural monitoring in mind – the size of one Landsat pixel lets us map even small farm fields in the U.S. And farmers and irrigation managers have harnessed the satellite’s data to improve the management of those fields as well.

With a new program called OpenET, they are improving the efficiency of irrigation in a water-parched region by using Landsat data to investigate how much water individual crop fields are soaking up.

screenshot of the OpenET program
A snapshot of the OpenET interface, showing different irrigation levels in crop fields.

The Spacecraft

We're launching Landsat 9 from Vandenberg Space Force Base, near the agricultural fields and vineyards of Lompoc, California.

image of Landsat spacecraft launch
Landsat-8 launch

Landsat 9 carries two instruments, similar to those on Landsat 8, to collect invaluable data on Earth below.

  • Operational Land Imager 2 (OLI-2)
    The Operational Land Imager 2 captures wavelengths of visible light as well as near infrared and shortwave infrared that reflect off Earth. Specific combinations of these wavelengths give us the natural color of a scene, the health of vegetation, the strength of a wildfire, and information beyond what we could see with our eyes.
  • The Thermal Infrared Sensor 2 measures the amount of heat emitted from Earth’s surface, which allows us to calculate surface temperature. This helps water managers track the health of plants, which cool down when they’re well-watered and growing.

The Landsat spacecraft provides power, navigation, data storage and more to the satellite.

From orbit, the Landsat 9 observatory continues the legacy of 50 years of Earth observations from space. The Landsat mission is the cornerstone of America’s land imaging program and will continue as NASA and USGS develop Landsat Next.

So… what would you explore?

Illustration of Landsat spacecraft above Earth

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