How Landsat recorded 50 years on a hot, changing planet

Around 2030, Landsat plans to launch its next satellite, called Landsat Next. It will bravely break number naming conventions. This will also be an upgrade.

“Even though Landsat 9 is still under construction, we’re talking to scientists in the community,” said Bruce Cook, a Goddard scientist on the upcoming iteration of the program, who asked what they wanted that Landsat 9 wouldn’t give them. The answer is simple. They want more frequent photos of each point, higher-resolution data, and finer wavelength bands: the instrument breaks the light into more detailed categories based on wavelength—kind of like a set of eight crayons and a set of 16 crayons difference between. These can reveal things like algal blooms, and their colors tell the story of their explosive growth. The team hopes that Landsat Next will visit every 9 days instead of every 16 days, have 26 bands instead of 11, and have a resolution of about 30 feet, showing a space about the length of six sidewalk squares.

But with hundreds of private Earth observation satellites in orbit, providing higher resolution data more frequently, why would governments need to run Landsat? Well, for one thing, Landsat data is free.

Over the past half century, Landsat has had several parents, including various government agencies and sometimes a private company. Today, it is jointly overseen by NASA and the USGS, which operate Landsat 8 and Landsat 9. (Other orbiters are now retired.) The price of satellite data dropped to $0 in 2008.

It’s a good deal compared to 1979, when the scene was only a few hundred dollars under government ownership. In the mid-1990s, when Landsat had private operators, that price had skyrocketed to $4,400 per scene. When the FBI took it back and launched the Landsat 7 in 1999, the price dropped, but it didn’t go away for nearly a decade, in part because the Internet made distribution and processing cheaper and less physical . No more tapes in the mail!

Today, Landsat data is held in the USGS archives and available to the public download free. Scientists around the world who previously could only buy one or three images can now click to download and enjoy. Nonprofits with tight checkbooks can do the same, as can researchers from countries that don’t have their own satellites. Other departments of the federal government — the Department of Agriculture, the Department of Defense — also use the data. You and all your curious compatriots also have access to various databases and tools depending on your needs and technical knowledge.

The point is that anyone — no matter the size of their wallet or the flag above a municipal building — can see the same view of the planet. “The importance of transparency cannot be overstated,” Morton said. “We all have the same basis for negotiating the future of our planet when we are all looking at the same data. I think it changes the balance of power when only a few people have this data.”

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