By means of Chris Burns, NASA’s Goddard Space Flight Center
For more than 50 years, the Landsat program has provided the longest continuous satellite record of the Earth’s land surface from space. Landsat 9, launched in 2021, is the latest mission in this incredible legacy – building on decades of Earth observation with upgraded technology, including improved radiometric resolution, improved signal-to-noise performance, and polar night thermal imaging. Working with Landsat 8 to map the entire planet every eight days, Landsat 9 data is integrated with the European Space Agency’s Sentinel-2 satellites to make near-daily global observations, delivering richer, more detailed observations that help scientists and the community monitor the changing planet.
VIDEO SCRIPT
It started over 50 years ago with an idea:
A satellite, orbiting the Earth, observing the surface of our planet, gathering data, day in, day out.
That idea gave birth to the Landsat program, a partnership between NASA and the US Geological Survey, the longest continuous record of Earth’s land surface from space.
The launch of Landsat 1 in 1972 was the first link in a chain of 8 satellites, each a building at the end.
And now, Landsat 9 carries that legacy forward.
Since its launch in 2021, Landsat 9 has helped collect more scenes per day than any previous Landsat satellite mission. collects as many scenes per day as Landsats 5 & 7 combined.
Working with Landsat 8, the pair now collects nearly 1,500 scenes per day, creating a complete map of the planet’s land surface every 8 days.
It’s not just about scale – it’s about Landsat’s ability to repeat the same scene multiple times a month. With this rapid acquisition, Landsat 9 helps track seasonal shifts in crops, the spread of forest fires, the aftermath of hurricanes, and even the rapid changes in glaciers and coastlines.
More images mean more data, boosting research and scientific applications around the world.
But when it comes to Landsat 9 imagery, it’s not just about quantity – it’s also about quality.
While the main design of Landsat 9 is almost the same as Landsat 8, it is able to collect data in greater detail thanks to an upgraded radiometric resolution – 14-bit instead of Landsat 8’s 12-bit.
Think of it like upgrading from a box of 4,000 crayons to one with 16,000 – every shade captured, every subtle detail sharpened.
Landsat 9’s quadrupled radiometric sensitivity makes a real difference in capturing data on the brightest surfaces on the planet, such as snow and ice,
Seeing many shades of detail is powerful, but only important if the picture itself is clear.
Landsat 9 not only sharpens what we can detect, it also cuts static, providing a stronger signal-to-noise ratio, which means interference-free images.
It’s like trying to hear a whisper in a noisy room — Landsat 9 silences the static so we don’t miss anything important.
And that clarity can make a difference, especially on dark surfaces like water that can harbor harmful algal blooms that spread quickly, threatening drinking water supplies, local wildlife and even human safety.
By observing these flowers with greater sensitivity, Landsat 9 provides communities and scientists with more reliable and actionable information to respond.
Landsat 9 doesn’t clock out when the sun goes down – its onboard thermal sensor, TIRS, measures the heat on our planet’s surface even in the dark.
This means that we can monitor urban heat islands, volcanic hotspots, and water temperature at night.
Since 2022, the special data request program of the US Geological Survey has implemented Landsat Extended Acquisition of the Poles, or LEAP for short, which takes advantage of Landsat 9’s ability to see in the dark to obtain images of the polar regions throughout the year when the sun can set for up to six months at the poles.
With Landsat 8, satellites can detect features such as meltwater, cracks, and even open water within the ice under low-light conditions.
The improved coverage will help scientists better monitor ice dynamics and weather changes in the polar regions, identifying spawning events, surface melting, and changes in sea ice extent even during dark months.
Landsat 9 does not work alone – it is part of a global group of satellites, where the collaboration of agencies and countries gives us the clearest, most consistent view of the Earth.
NASA’s Harmonized Landsat Sentinel-2 project combines data from Landsats 8 & 9 with the European Space Agency’s Sentinel-2 A,B and C satellites to form a seamless, consistent surface reflectance record.
To this “virtual constellation,” Landsat 9 contributes its spectral precision and calibrated data, helping to make global observations every 1-2 days at 30-meter resolution.
Landsat 9’s high fidelity, radiometric stability, and continuous anchoring of HLS, ensure that the integrated product maintains the scientific integrity that Landsat users expect.
Landsat 9 is more than just a mission today — it’s part of the foundation for the future.
Through the Sustainable Land Imaging program, NASA and the US Geological Survey aim to preserve our ability to keep a continuous, reliable record of Earth’s land for decades to come.
That means not only flying satellites, but building the technology, partnerships, and planning needed to keep the record unbroken.
Within SLI, NASA’s Sustainable Land Imaging–Technology initiative is testing new instruments that will make future missions smaller, more capable, and more efficient.
Landsat 9 was NASA’s first SLI mission and played a key role here, setting the benchmark for data quality and coverage, proving what works today and guiding tomorrow’s technologies.
Its stability and accuracy are the hallmarks of past lessons learned, allowing scientists to rely on the record for decades, and its success will help guide the innovations that come next.
For more than half a century, Landsat satellites have provided us with an unbroken record of our changing planet.
In just four years, Landsat 9 brought that vision into sharper focus — capturing millions of scenes, advancing how we track water, ice, and land, and solidifying the longest observational record on Earth.
It’s not just another satellite in orbit. It’s a bridge — bringing the Landsat legacy forward with improved technology while laying the groundwork for the future of sustainable earth observation.
Because with Landsat, each image is more than a photograph — it’s a calibrated digital record, providing knowledge we can use to understand, protect, and sustain life on Earth.
Source link
