Though it might not be as well-known as the Hubble Space Telescope or the James Webb Space Telescope, NASA’s Landsat 7 has significantly enhanced our understanding of our planet. For over 25 years, it has been capturing the stunning landscapes of Earth from space, documenting remarkable details of the planet’s ever-changing environment.
Launched in 1999 with an expected mission duration of only five years, Landsat 7 has instead emerged as one of the longest-running Earth observation missions in history. While it doesn’t gaze into distant galaxies, its instruments are focused on the vibrant, living surfaces of Earth instead.
From an altitude of 700 km (about 435 miles), it has produced vital data for scientific research and conservation, showcasing stunning images of dynamic deserts, glaciers, forests, and coastlines.
“[Landsat 7 has] been essential in tracking environmental changes such as natural disasters, deforestation, and urban expansion,” said David Applegate, former director of the US Geological Survey.
“It documented significant events such as Hurricane Katrina in 2005, the Haiti earthquake in 2010, the Australian wildfires from 2019 to 2020, and rapid urban growth across the globe.”
The Landsat 7’s primary sensor, the Enhanced Thematic Mapper Plus (ETM+), captured in the clean room at Lockheed Martin Space Systems. Photo Credit: NASA/Raytheon
Landsat 7 is scheduled to retire this month after covering 6.1 billion km (3.8 billion miles) in space and capturing over 3 million images. A carefully planned shutdown will involve depleting its batteries, turning off the fuel line heater, and rendering the communications system silent permanently. For another 55 years, the satellite will drift silently above Earth before eventually re-entering the atmosphere and burning up.
As we bid farewell, we reflect on its lens and celebrate the beauty and complexity of our planet, revealing both the impacts of deforestation and the intricate patterns of continents.
Coral Reef Conservation
In the first year of the Landsat 7 mission, detailed images of coral reefs were gathered from around 900 locations worldwide. These vibrantly colored swirls depict atolls, enclosed coral reefs that typically surround a lagoon, often formed from eroded volcanic islands. Photo Credit: NASA Goddard Space Flight Center Science Visualization Studio
Guinea-Bissau, West Africa
Guinea-Bissau, a small country in West Africa, showcases intricate patterns evident in the shallow waters along its coast, where silt from the Geba and other rivers is carried away by the Atlantic Ocean. Photo Credit: NASA/USGS
Siberia, Dragon Lake
Dragon Lake, formed by the Bratsk Reservoir along the Angara River in southern Siberia, Russia, is shown here frozen in winter. Photo Credit: NASA/USGS
Lena Delta, Siberia
The Lena River, approximately 4,500 km long, is among the largest rivers globally. The Lena Delta Reserve is the most extensive protected wilderness area in Russia, serving as a sanctuary and breeding ground for many Siberian wildlife species. Photo Credit: NASA/USGS
9/11, New York
This true-color image was captured on September 12, 2001, by the Enhanced Thematic Mapper Plus (ETM+) sensor on the Landsat 7 satellite shortly after the Twin Towers fell. Photo Credit: USGS/EROS
Comprehensive Continental Mosaic of Antarctica
A complete continental mosaic of Antarctica was constructed using images from Landsat 7. Photo Credit: NASA/USGS
Bolivian Deforestation
Once a vast expanse of lush vegetation, the Amazon rainforest is rapidly changing. This image demonstrates the significant deforestation occurring in Bolivia’s portion of the Amazon Basin, where loggers have carved extensive paths while ranchers have cleared areas for grazing. The bright red areas indicate healthy vegetation. Photo Credit: NASA/USGS
Icefall, Lambert Glacier, Antarctica
Lambert Glacier, the largest glacier in the world, features an ice waterfall that nourishes the glacier from the expansive ice sheets covering the plateau. The ice flows slowly, resembling water, descending about 1,300 feet (400 meters) to the underlying glacier. Photo Credit: NASA/USGS
Deepwater Horizon Oil Spill
On April 20, 2010, a catastrophic oil spill followed an explosion at an oil well in the Gulf of Mexico. Efforts to contain the expanding oil slick began immediately. Landsat imagery provided by the US Geological Survey reveals the extent of the spill, with Landsat data being vital for monitoring its range and movement. Photo Credit: NASA/USGS
Westfjords, Iceland
The Westfjords are a series of peninsulas located in northwestern Iceland. Though they comprise less than one-eighth of the country’s land area, their rugged coastlines account for over half of Iceland’s total coastline. Photo Credit: NASA/USGS
“Spilled Paint”: Iran’s Dasht-e Kavir
Resembling spilled paint, this image showcases a vibrant tapestry of landscapes in Iran’s largest desert, Dasht-e Kavir, or Great Salt Desert. It spans approximately 77,000 square kilometers (29,730 square miles) and consists of dry stream beds, desert plateaus, and salt marshes. Extreme temperatures and dramatic daily fluctuations, alongside severe storms, are characteristic of this harsh environment. Photo Credit: NASA/USGS
Hurricane Katrina, New Orleans
Following Hurricane Katrina, which led to severe flooding of up to 80% of New Orleans, Landsat 7 captured this image on September 15, 2005. Two and a half weeks post-hurricane, efforts were ongoing to siphon water back into Pontchartrain Lake, with pumps extracting approximately 380 cubic meters of water every second. Photo Credit: USGS/CEROS
Namib Naukluft National Park, Namibia
Namib Naukluft National Park is an ecological reserve in the Namib Desert, where coastal winds give rise to the world’s tallest dunes, which can reach 980 feet (300 meters). Photo Credit: NASA/USGS
Vatnajökull Glacier Ice Cap, Iceland
This image features blue ice fingers breaking away from the Vatnajökull glacier in Iceland’s Skaftafell National Park, situated at the southern extremity of Europe’s largest ice cap. Photo Credit: NASA/USGS
Uppsala Glacier Retreat in Argentina
Landsat images captured in 1986, 2001, and 2014 illustrate the retreat of the Uppsala Glacier. Photo credit: NASA
