It may not be a household name like the Hubble Space Telescope or the James Webb Space Telescope, but NASA’s Landsat 7 has quietly transformed how we see our planet. For more than 25 years, it’s captured breathtaking views of Earth from orbit, chronicling our planet’s dynamic landscapes in unprecedented detail.
Launched in 1999 with a planned mission of just five years, Landsat 7 became one of the longest-running Earth observation missions in history. While it didn’t peer into distant galaxies, it focused its lens on something equally remarkable: the living, breathing surface of Earth.
From 700km (about 435 miles) above us, it provided critical data for science and conservation while delivering striking images of deserts, glaciers, forests, and coastlines in flux.
“[Landsat 7 has] been pivotal in documenting environmental changes such as natural disasters, deforestation, and urban growth over its 25 years,” said David Applegate, former director of the US Geological Survey.
“[It captured] significant events like Hurricane Katrina in 2005, the Haiti earthquake in 2010, the Australian bushfires in 2019 - 2020, the dramatic growth of cities worldwide and more through its long-standing mission.”
The Enhanced Thematic Mapper Plus (ETM ) instrument, the primary sensor on the Landsat-7, was photographed in the clean room of Lockheed Martin Space Systems. Photo credit: NASA/Raytheon
Now, after logging 6.1 billion km (3.8 billion miles) in orbit and capturing over 3 million images, Landsat 7 is set to retire this month. In a meticulously planned farewell, its batteries will be drained, its fuel-line heaters switched off, and its communication systems permanently silenced. The satellite will drift quietly above Earth for another 55 years before eventually reentering the atmosphere and burning up.
As we say goodbye, we look back through its lens to celebrate the beauty and complexity of our world, from deforestation to continent mosaics.
Coral Reef Conservation
Detailed images of reefs from nearly 900 locations around the world have been collected in the first year of the Landsat 7 mission. These elegant whorls of colour are atolls: enclosed coral reefs that almost always surround a lagoon. Generally speaking, atolls are the products of volcanic islands that have eroded. Picture Credit: NASA Goddard Space Flight Center Scientific Visualization Studio
Guinea-Bissau, West Africa
Guinea-Bissau is a small country in West Africa. Complex patterns can be seen in the shallow waters along its coastline, where silt carried by the Geba and other rivers washes out into the Atlantic Ocean. Picture Credit: NASA/USGS
Dragon Lake, Siberia
Nicknamed 'Dragon Lake', this body of water is formed by the Bratsk Reservoir, built along the Angara River in southern Siberia, Russia. This image was acquired in winter, when the lake is frozen. Picture Credit: NASA/USGS
Lena Delta, Siberia
The Lena River, some 4,500km long, is one of the largest rivers in the world. The Lena Delta Reserve is the most extensive protected wilderness area in Russia. It is an important refuge and breeding ground for many species of Siberian wildlife. Picture Credit: NASA/USGS
9/11, New York
This true-colour image was taken by the Enhanced Thematic Mapper Plus (ETM ) sensor aboard the Landsat 7 satellite on September 12, 2001, at roughly 11:30 a.m. A day after the attack, smoke continues to billow out of the collapsed Twin Towers in New York, USA. Picture Credit: USGS/EROS
Full continent mosaic of Antarctica
Landsat 7 imagery was used to create a full continent mosaic of Antarctica. Picture Credit: NASA/USGS
Bolivian Deforestation
Once a vast carpet of healthy vegetation, the Amazon rain forest is changing rapidly. This image of Bolivia shows dramatic deforestation in the Amazon Basin. Loggers have cut long paths into the forest, while ranchers have cleared large blocks for their herds. Fanning out from these clear-cut areas are settlements built in radial arrangements of fields and farms. Healthy vegetation appears bright red in this image. Picture Credit: NASA/USGS
Icefall, Lambert Glacier, Antarctica
The Lambert Glacier in Antarctica is the world's largest glacier. The focal point of this image is an icefall that feeds into the glacier from the vast ice sheet covering the polar plateau. Ice flows like water, albeit much more slowly. Cracks can be seen in this icefall as it bends and twists on its slow-motion descent 1300 feet (400 meters) to the glacier below. Picture Credit: NASA/USGS
The Deepwater Horizon oil spill
April 20, 2010, an explosion at an oil well in the Gulf of Mexico resulted in a major oil spill. Since then, emergency response efforts have been underway to contain the growing oil slick before it reaches the southern coast of the United States. Landsat imagery, acquired by the U.S. Geological Survey, shows the extent of the oil slick. The Landsat data are being used to monitor the extent and movement of the slick. Picture Credit: NASA/USGS
West Fjords, Iceland
The West Fjords are a series of peninsulas in northwestern Iceland. They represent less than one-eighth of the country's land area, but their jagged perimeter accounts for more than half of Iceland's total coastline. Picture Credit: NASA/USGS
'Spilt Paint': The Dasht-e Kavir, Iran
Like poster paints running wild, this image reveals an eclectic montage of landscapes in Iran's largest desert, the Dasht-e Kavir, or Great Salt Desert. The word kavir is Persian for salt marsh. The almost uninhabited region spans an area of more than 77,000 square kilometres (29,730 square miles) and comprises a mix of dry streambeds, desert plateaus, mudflats, and salt marshes. Extreme heat, dramatic daily temperature swings, and violent storms are the norm in this inhospitable place. Picture Credit: NASA/USGS
Hurricane Katrina, New Orleans
The floods that buried up to 80 per cent of New Orleans had noticeably subsided by September 15, 2005, when the top image was taken by the Landsat 7 satellite. In the two and a half weeks that had passed since Hurricane Katrina flooded the city, pumps had been working nonstop to return the water to Lake Pontchartrain. As portable pumps were brought in to supplement the permanent pumps already hard at work, as much as 380 cubic meters of water were being pumped out of New Orleans every second, according to the U.S. Army Corps of Engineers. Picture Credit: USGS/CEROS
Namib-Naukluft National Park, Namibia
Namib-Naukluft National Park is an ecological preserve in Namibia's vast Namib Desert. Coastal winds create the tallest sand dunes in the world here, with some dunes reaching 980 feet (300 meters) in height. Picture Credit: NASA/USGS
Vatnajökull Glacier Ice Cap, Iceland
Valley glaciers appear as fingers of blue ice reaching out from the Vatnajökull Glacier in Iceland's Skaftafell National Park. The park lies on the southern edge of Vatnajokull, Europe's largest ice cap. Picture Credit: NASA/USGS
Upsala Glacier Retreat, Argentina
Landsat images from 1986, 2001 and 2014 show the retreat of the Upsala glacier. Picture Credit: NASA
