For the last 50 years, a series of NASA satellites have been doing something that has become increasingly important in recent years due to climate change – keeping a continuous eye on our changing planet from space.
The Landsat Program has catalogued the earth’s changing landscapes, from the rise of the megacities to the decline of forests, glaciers, and the evolution of deserts and coastlines.
It has been used to monitor the behaviour and habitat of various species of wildlife, from wildebeest in the African savannah, to the walruses in Antarctica. According to NASA, it is the most economically impactful Earth science program in history. While there have many technically advanced imaging satellites, none have been close to Landsat in longevity and reliability.
Some of the stunning images captured by Landsat
Coastal Colour in New Zealand.
Landscape in Southern Louisiana.
Fire Consumes Large Swaths of Greece.
A joint effort by the United States Geological Survey and NASA, the first Landsat satellite, formerly known as the Earth Resources Technology Satellite, was launched in July 1972. In the last five decades, seven more satellites were launched in a series to replace the last. In 1982, the Landsat – 4 became the first satellite that could capture details as small as 30 meters across the ground.
Early this morning (02:12 P.M. EDT, Sep 27), the newest satellite in the program, the Landsat – 9 blasted off from Vandenberg Space Force Base in California and successfully made it into orbit.
Orbiting at an altitude of 700 kilometers above sea level, Landsat – 9 will start acquiring images of the earth in tandem with its predecessor the Landsat – 8, which was launched in 2013, and replace the aging Landsat – 7, which launched way back in 1999.
Landsat Timeline. Credits: NASA
According to NASA, the mission cost around $750 million and carries two crucial instruments – the Thermal Infrared Sensor 2 and the Operational Land Imager 2. The two instruments can detect minute changes in the world ecosystems such as lakes, forests, and rivers.
“We’ve assembled an amazing history of how the planet has changed over the last half-century,” said Dr. Jeff Masek, a project scientist for the program. “We can see the natural disturbances that occur, fires, hurricanes, and insect outbreaks; and then the long-term recovery of ecosystems that takes place for decades after that.
“And we’re able to look specifically at climate and climate-change impacts on ecosystems,” he said. “We’ve mapped areas of increased plant cover at high latitudes due to a warming climate. We’ve also seen areas of vegetation decline in water-limited semi-arid environments.”
Check out more stunning images of Landsat here.
Cover Image: United Launch Alliance