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Landsat 9 returns its 1st Earth images

Landsat 9: Feather-like patterns of white snow-capped mountains with tan, brown and teal valleys.
View larger. | The latest Earth-observing Landsat satellite – Landsat 9 – acquired its first images of Earth on October 31, 2021. Here’s its view of the snow-capped Himalayan Mountains. You can make out lakes made from glacial meltwater within the icy white regions toward the top center of this image. The lighter terrain at lower left is Kathmandu, Nepal. Mount Everest is just out of frame to the right. Earlier Landsats have documented the shrinking glaciers of this region. Image via NASA/ USGS.

Landsat 9 returns 1st Earth images

Most of us don’t remember the days before the Landsats and other Earth-observing satellites. How did people back then know what Earth changes were taking place? NASA launched Landsat 1 in 1972. And NASA launched its latest Landsat – Landsat 9 – on September 27, 2021. This newest Earth-observing satellite returned its first Earth images on October 31. NASA released Landsat 9’s first-light images on November 5. NASA administrator Bill Nelson said:

Landsat 9’s first images capture critical observations about our changing planet and will advance this joint mission of NASA and the U.S. Geological Survey (USGS) that provides critical data about Earth’s landscapes and coastlines seen from space.

Nelson said the Landsat program has:

… the proven power to not only improve lives but also save lives.

And that’s surely going to be increasingly true as global warming continues, bringing about rising seas and more weather extremes. We now have nearly 50 years of Earth observations from space. NASA said Landsat will help humanity manage natural resources and get a better understanding of the impacts of climate change. And just in time, too, don’t you think? Where would we on Earth be today, without this space-based Earth-observing technology?

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Teal water with beige swirls around edge of dark brown and olive land.
View larger. | This Landsat 9 image from October 31, 2021, shows the swirling sediments in light brown mixing with the teal waters of Lake Erie and Lake St. Clair near Detroit, Michigan, and Windsor, Ontario, Canada. Landsat 9 monitors these giant sources of freshwater, observing green algae and identifying harmful blooms early. Image via NASA/ USGS.

First-light images

Landsat 9 replaces the Landsat 7; Landsat 8 is still in operation. Scientists point to upgrades with Landsat 9 that include the ability to differentiate between 16,000 shades of a given wavelength of color. In other words, subtle changes on Earth will become clear with the new data. The new satellite is still performing test runs. It’s undergoing a 100-day period during which scientists will test its systems and calibrate its instruments. Then USGS will take the reins, likely in January. Eventually, Landsat 9 and Landsat 8 are expected to acquire about 1,500 Earth images daily, covering the globe every eight days.

The first-light images put a spotlight on Detroit, the Florida Panhandle, the American Southwest’s Navajo Nation, the western coast of Australia and the Himalayas. Jeff Masek, a project scientist on Landsat 9, commented:

First light is a big milestone for Landsat users. It’s the first chance to see the kind of quality that Landsat 9 provides. And they look fantastic. When we have Landsat 9 operating in coordination with Landsat 8, it’s going to be this wealth of data, allowing us to monitor changes to our home planet every eight days.

Popcorn clouds over green lowlands with thin white curve of beach at edge of navy blue water.
View larger. | This Landsat 9 image from October 31, 2021, captures the white sand beaches of the Florida Panhandle from Pensacola Beach all the way down to Panama City Beach. Landsat 9 will keep its eagle eye on the coastlines for potential impacts from rising sea levels. Image via NASA/ USGS.

Instruments on Landsat 9

Landsat 9 houses two science instruments: the Operational Land Imager 2 (OLI-2) and the the Thermal Infrared Sensor 2 (TIRS-2).

The Operational Land Image 2 detects visible, near-infrared and shortwave-infrared light in nine wavelengths.

The Thermal Infrared Sensor 2 detects thermal radiation in two wavelengths to measure Earth’s surface temperatures and its changes.

These instruments will provide Landsat 9 users with data at a scale where they can separate human and natural causes of change. Karen St. Germain, Earth Science Division director at NASA Headquarters in Washington, said:

The data and images from Landsat 9 are expanding our capability to see how Earth has changed over decades. In a changing climate, continuous and free access to Landsat data, and the other data in NASA’s Earth observing fleet, helps data users, including city planners, farmers and scientists, plan for the future.

Popcorn clouds over brown landscape with heavily indented shoreline and navy and teal ocean.
View larger. | Landsat 9 took this image of Western Australia on October 31, 2021. This image shows popcorn-shaped clouds (cumulus) over land with some higher cirrus clouds. Mangroves cluster along the shore of the country, providing a protective barrier from storms and erosion. Mitchell River National Park lies near the center of the image, with the Coronation Islands at lower left and Bigge Island to the upper left in the Indian Ocean. Image via NASA/ USGS.

Monitoring Earth from above

This eye-from-the-sky view on Earth helps us on the ground get a better picture of what’s happening on our planet. Scientists hope to be able to have weekly tropical deforestation alerts, water quality monitoring, and crop condition reports, among other helpful insights that Landsat 9 can provide on a regular basis. USGS Acting Director Dr. David Applegate said:

The incredible first pictures from the Landsat 9 satellite are a glimpse into the data that will help us make science-based decisions on key issues including water use, wildfire impacts, coral reef degradation, glacier and ice-shelf retreat and tropical deforestation. This historic moment is the culmination of our long partnership with NASA on Landsat 9’s development, launch and initial operations, which will better support environmental sustainability, climate change resiliency and economic growth – all while expanding an unparalleled record of Earth’s changing landscapes.

Orbital view of brown and dark green land with a few white clouds.
View larger. | This image is of the Navajo Nation in the southwestern United States on October 31, 2021. Landsat 9 will help monitor drought conditions and manage irrigation water in regions such as this. As NASA said, “With only 85 rain gauges to cover more than 27,000 square miles, satellite data and climate models are filling the gaps to help the Navajo Nation monitor drought severity.” Image via NASA/ USGS.

Bottom line: Landsat 9 took its first images of Earth on October 31, 2021. Enjoy these views of Earth from space, as Landsat 9 begins its monitoring of the land below.

Via NASA

The post Landsat 9 returns its 1st Earth images first appeared on EarthSky.

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