How Landsat recorded 50 years on a volatile, fiery planet


Around 2030 The Landsat program will launch its next satellite, called Landsat Next. It will boldly break away from numerical naming convention. It will also be an upgrade.

“Even when Landsat 9 was still being built, we talked to scientists in the community,” says Bruce Cook, Goddard scientist for the upcoming iteration of the program, asking what they wanted that Landsat 9 wouldn’t give them. The answers were direct. They wanted images of each point more often, higher-resolution data, and finer bands: the instruments would divide the light into finer categories according to its wavelength—something like the difference between a set of eight crayons and one with 16. They can detect things like outbreaks of algal blooms, whose the colors tell the story of their explosive growth. The team hopes Landsat Next will visit spots every nine days instead of every 16, have 26 bands instead of 11, and have a resolution of about 30 feet, showing areas that are about six square feet of sidewalk on a side.

But with hundreds of private Earth observation satellites in orbit, often providing higher resolution data, why should the government run Landsat at all? Well, for one thing, Landsat data is free.

Over the past half century, Landsat has had several parents, including various government agencies and, at one point, a private company. Today it is jointly monitored by NASA and the USGS, which operate both Landsat 8 and Landsat 9. (The other orbiters are now decommissioned.) The cost of satellite data dropped to $0 in 2008.

That’s cheap compared to 1979 when, under state ownership, stages cost a few hundred dollars. That price jumped to $4,400 per scene in the mid-90s when Landsat had a private operator. When the feds took it over and launched Landsat 7 in 1999, prices fell but didn’t disappear for nearly a decade, in part because the Internet made distribution and processing cheaper and less physical. No more cassettes in the mail!

Today, Landsat data lives on in the USGS archives and is available to the public for free download. Scientists around the world, who previously could only afford to buy one or three images, can now click Download to their heart’s content. Nonprofit organizations with tight checkbooks can do the same, as can researchers from countries without their own satellites. Other branches of the federal government—the Department of Agriculture, the Department of Defense—also use the data. So can you and all your curious compatriots, using various databases and tools according to your needs and technical knowledge.

The point is that everyone—regardless of the size of their wallet or the flag above their civic buildings—can see the same views of Earth. “It’s hard to overstate how important that transparency is,” says Morton. “When we all look at the same data, we all have the same basis for negotiating the future of our planet. I think when only a few people have that data, it changes the balance of power.”



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