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From 438 miles above Earth’s surface,

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the newest Landsat satellite will collect data so detailed,

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it can detect both natural and

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human-caused changes to the landscape.

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But what really makes Landsat unique

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is the half-century of data,

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an unbroken chain of observations over five decades.

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Let’s take a look at how we got here.

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1966 – The US Geological Survey proposes a satellite

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to study Earth’s land masses.

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But what would that look like?

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Over the next few years,

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USGS and NASA research their options.

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1970 – NASA gets the green light to build

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an Earth Resources Technology Satellite,

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an experiment to study and monitor

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our planet’s land surface from space.

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Launched in ’72,

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this was the first digital data of Earth,

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repeated at regular intervals, with geometric fidelity

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to allow comparison between observations.

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This changed how we drew maps,

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tabulated agricultural production,

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and assessed damage after disasters.

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In 1975, NASA launched a second satellite,

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similar to the first.

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Now they were collecting twice as much data.

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With Landsat 3 replacing the aging original in ’78,

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focus shifted to the advanced technology planned for the 80s.

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The Thematic Mapper instrument,

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launched on Landsat 4 in 1982

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and on its twin Landsat 5 in ‘84,

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was a major step forward.

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Collecting seven different wavelengths,

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at better ground resolution, and with higher precision,

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this was the beating heart of the satellite

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and became the work horse for a generation of scientists.

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For the first time, Landsat data had three visible bands

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– red, green, and blue –

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allowing natural-color composite images.

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And with the addition of short-wave infrared wavelengths,

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the data could better highlight flooded areas,

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mineral deposits, and burn scars from wildfires.

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The thermal bands were also upgraded

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allowing individual farm fields to be tracked.

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The sixth Landsat was intended

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to be another big step forward,

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but it never reached orbit after launch in 1993.

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Plans immediately began for Landsat 7,

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which would carry an even more improved sensor.

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At the time, the Enhanced Thematic Mapper Plus

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was the most stable Earth observation instrument

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ever sent into orbit, and the calibration

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could be updated while in space.

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For the first time,

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we had an instrument robust enough

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to collect lots of data,

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and we had a plan to thoroughly record the entire globe.

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Landsat 7 was put to work mapping coral reefs,

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and even produced the first

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high-resolution natural-color map

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of remote Antarctica.

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Improvements to the thermal bands on Landsat 7

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allowed states and counties

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to gauge how much water was used by crops.

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This helps manage water resources efficiently.

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An important milestone occurred in 2008,

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when the USGS made the data available to download for free.

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Users were able to get the data they needed,

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and not just what they could afford.

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It really unlocked a ton of innovation

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and created about 2 billion dollars a year

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in economic benefits.

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The modern era of Landsat observations

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began with the launch of Landsat 8 in 2013.

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Having a push-broom style sensor on Landsat 8

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was a big improvement over the older scanning sensor.

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The Landsat 8 ground system that USGS runs

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is capable of receiving a lot more data than before.

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We’re downloading over 725 scenes each day.

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That just wasn’t remotely possible until Landsat 8.

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The two European Sentinel-2 satellites

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were designed to mesh with Landsat

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so that users can treat data from all the satellites

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as if it came from one single source.

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Now we get observations every 2 or 3 days,

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instead of every 2 weeks.

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2021 is the launch of Landsat 9. the next step forward.

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It will collect the best data ever recorded by a Landsat satellite,

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while still integrating seamlessly with the extensive archive.

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Since the early 1970s,

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Landsat satellites have allowed us to better manage our resources.

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Landsat data has enabled countless innovations

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and will let us track the effects of climate change into the future.