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Godspeed, Artemis II!

2026-03-31 15:54

The Artemis program patch in the space station's cupola. The patch is framed by the center circular window in the space. Earth can be seen behind the patch. The Artemis patch has five sides. It has a white background with a black border. There's a black "A," for Artemis. The crossbar of the A is made by a curving red trajectory line that crosses from left to right. That line continues beyond the "A" and beyond a small gray circle representing the Moon. Below the "A" is a blue crescent representing Earth. At the very bottom is the word "Artemis."

NASA/Jessica Meir

NASA astronaut Jessica Meir took this photo of an Artemis program patch floating in the International Space Station’s cupola. She posted it on X on March 30, 2026, with the following caption: “Our work on the @Space_Station has provided the foundation to explore further, preparing us to return humans to the Moon this week. Stay tuned as we enter the @NASAArtemis era! Expedition 74 will certainly be keeping a close watch. Godspeed, Artemis II!”

Image credit: NASA/Jessica Meir

Landsat Reveals Reservoir Changes and Bathymetry

2026-03-31 14:30

Communities worldwide rely on reservoirs for drinking water, hydroelectric power, irrigation, and more. These critical freshwater resources are affected by seasonal and long-term changes; water levels in reservoirs can dip during hot summer months or due to prolonged drought, or can flood after a particularly strong storm. Despite their importance, there are key gaps in our knowledge of reservoir structure and dynamics. Two recent papers use Landsat data to help fill in those gaps.

Researchers from the University of Southampton used Landsat data to identify where water advanced or retreated from 1984 to 2022, creating the first global dataset pinpointing the exact year of permanent surface water changes—such as when a reservoir formed or a stream dried up. The study can track changes in streams as narrow as 30m and lakes as small as 900m². In a separate study, Texas A&M University researchers used Landsat data to build a global bathymetry dataset called ‘3D-LAKES’ that enables water managers to estimate reservoir storage capacity.

In this output from the 3D-LAKES dataset, green represents shallow waters while purple represents deeper waters. The data is overlaid on an image collected by the Thematic Mapper (TM) on Landsat 5 on July 31, 1985 and a Copernicus Digital Elevation Model (DEM) and bathymetric data from the 3D-LAKES dataset.

Ross Walter/NASA

The above animation shows the Amistad Reservoir on the border of Texas and Mexico. It uses a natural-color Landsat image from 1985 overlaid onto a Copernicus Digital Elevation Model (DEM) and bathymetric data from the 3D-LAKES dataset. Vertical relief is exaggerated by a factor of four to emphasize topographic features and landforms. The reservoir is jointly managed by the U.S. and Mexico through the International Boundary and Water Commission (IBWC) for flood control, recreation, and hydroelectric power. Despite its importance to the two countries, the reservoir is slowly shrinking. The surface water transitions dataset shows the water levels retreating in recent decades, with significant recessions between 2012 and 2016. The 3D-LAKES dataset reveals the underwater shape of the reservoir. Together, these datasets complement the in situ water level and conditions data collected throughout the year.

Tracking Surface Water Transitions

Human communities both shape and are shaped by water. We divert rivers, build reservoirs, and construct artificial islands, while natural forces—storms, meandering rivers, and rising seas—reshape our waterways and coastlines. With satellite data as an important tool to study ecosystem dynamics, researchers have begun to build a more comprehensive global understanding of where water is and how it shifts over time. In their water transitions study, the University of Southampton team focused specifically on permanent changes in lakes, rivers, coastlines, and other water bodies worldwide.

Looking at long-term changes in surface water can help scientists understand drivers of change, said Gustavo Willy Nagel, lead researcher on the paper. Knowing when a lake began receding helps water managers investigate whether drought, irrigation, or other forces caused the decline.

Running from July 31, 1985 to November 10, 2025, this animation shows the Amistad Reservoir levels fluctuate with the seasons but slowly decline. The time series is composed of images from Landsats 5, 7, 8, and 9.

Ross Walter/NASA

Scientists, policymakers, and water managers can explore the interactive dataset that Nagel and his team created to visualize changes close to home as well as stark global impacts such as the drying of the Aral Sea, the lakes created by melting glaciers in Tibet, and the building of the Palm Islands in Dubai.

Assessing long-term changes in surface water presents a key challenge, as surface water is extremely dynamic. Seasonal fluctuations and climatic forces mean that rivers, lakes, and coastlines are changing all the time. To identify permanent water changes while excluding seasonal fluctuations, the researchers ran two algorithms. The first detected whether the water body was advancing or retreating over the study period using the Modified Normalized Difference Water Index (mNDWI), which uses the shortwave-infrared (SWIR) instead of the near-infrared (NIR) band. The second algorithm used the Green_Red Normalized Difference Water Index (grNDWI)—an index proposed by the research team—to identify the precise year that the water body transitioned. A change was considered “permanent” if it did not revert to its previous condition during the study period of 1984 to 2022.

“The dataset is showing, for every location on the planet, areas where water advanced or retracted and the year of that change,” said Nagel.

In this screenshot from the Water Change Time Detection tool on Google Earth Engine, red and orange represent areas where water receded, whereas blue represents areas where water advanced. Overall water levels have receded, including major recessions between 2012 and 2016.

Visualizing Lakes in 3D

Landsat can help us monitor surface water. But what about what’s under the surface?

In a study published in Scientific Data in October 2025, researchers from Texas A&M University fused Landsat and ICESat-2 data to create bathymetry maps for half a million global lakes and reservoirs. The research team, led by Huilin Gao, used Landsat imagery to calculate the surface area of water bodies, delineate where water meets land, and track how water extent changes over time. Then, they combined laser altimetry from the ICESat-2 satellite to infer the underwater bathymetry of water bodies. With these measurements, the scientists refined area-elevation relationships, a key metric for understanding how water storage changes with water level.

In this screenshot from the 3D-LAKES dataset, green represents shallow waters while purple represents deeper waters. Comparing this screenshot to the results from the water change detection tool, it appears that the areas where water receded align with the shallower portions of the reservoir.

The resultant dataset, dubbed 3D-LAKES, is static, as bathymetry does not tend to change significantly year to year. “This dataset can support many applications, from monitoring water storage to refining hydrological models,” said Chi-Hsiang Huang, the study’s lead author.

3D-LAKES can be used in combination with Landsat-based maps—like the surface transition research or the popular Global Surface Water dataset—to help water resource managers assess the volume of water held in a reservoir or lake. This allows them to evaluate flood risk, map habitat, or calculate how much water is available during a particularly dry season. Researchers can also track changing water volume over time, helping understand long-term trends in water storage.

Measuring underwater topography has historically been expensive and impractical at global scales. The 3D-LAKES dataset now provides researchers and managers with crucial bathymetric data for lakes and reservoirs worldwide. “With this new dataset, we can achieve a more comprehensive understanding of the impacts of lakes and reservoirs on regional climatology, water security, and ecosystem services,” said Gao. Both studies provide water and land managers with unprecedented tools for resource management and planning—from the Amistad Reservoir to the Australian Outback to the Brazilian Amazon.

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Fires Tear Through Nebraska Grasslands

2026-03-31 04:01

February 28, 2026

March 29, 2026

Plains in western Nebraska, divided by the North Platte River, appear in light shades of green and brown in a false-color satellite image.

NASA Earth Observatory / Lauren Dauphin

A burned area on the plains of western Nebraska appears as a large tan area in a false-color satellite image.

NASA Earth Observatory / Lauren Dauphin

Plains in western Nebraska, divided by the North Platte River, appear in light shades of green and brown in a false-color satellite image.

NASA Earth Observatory / Lauren Dauphin

A burned area on the plains of western Nebraska appears as a large tan area in a false-color satellite image.

NASA Earth Observatory / Lauren Dauphin

February 28, 2026

March 29, 2026

Acquired with the VIIRS (Visible Infrared Imaging Radiometer Suite) on the NOAA-21 satellite on February 28 and March 29, 2026, these false-color images (bands M11-I2-I1) show grasslands in western Nebraska before and after several wildland fires spread through the area. NASA Earth Observatory/Lauren Dauphin.

On the afternoon of March 12, 2026, a wildland fire ignited in Morrill County, Nebraska. Within 12 hours, high winds had propelled flames approximately 70 miles (110 kilometers) east-southeast across the prairie. The Morrill fire would burn over 640,000 acres (260,000 hectares) within a week, becoming the largest wildfire in the state’s history.

This image (right) shows the extent of recently burned areas near the North Platte River in western Nebraska on March 29. By this time, authorities reported the Morrill fire was 100 percent contained. However, crews were working to contain two smaller blazes immediately to the northeast, the Ashby and Minor fires, which ignited early on March 26. For comparison, the left image was acquired on February 28, before the fires. Both are false-color to better distinguish the burned areas.

The fires occurred amid an active start for wildfires in the U.S. in 2026. The National Interagency Fire Center (NIFC) reported that 15,436 fires had burned 1,510,973 acres nationwide as of March 27. That’s far higher than the 10-year average—9,195 fires burning 664,792 acres—for the same period.

The Great Plains have been particularly prone to fire in early 2026. Exceptionally dry fuels contributed to rapid fire growth and other unusual fire behavior for the time of year, according to the NIFC. Throughout the winter, much of the region saw warmer and windier-than-average conditions, as well as less than 50 percent of average precipitation over a 90-day period, leading to low soil moisture and grass fuels that were primed to burn.

The fires in western Nebraska affected large areas of ranch and pasture lands, destroyed homes, barns, and fences, and injured or killed livestock, according to news reports. The Morrill fire also burned much of the Crescent Lake National Wildlife Refuge in the Nebraska Sandhills, an area of grasslands, wetlands, and dunes used by migratory birds. Despite the fires, reports indicate that hundreds of thousands of sandhill cranes are still making their annual migration through the Platte River valley.

NASA Earth Observatory images by Lauren Dauphin, using VIIRS data from NASA EOSDIS LANCE, GIBS/Worldview, and the Joint Polar Satellite System (JPSS). Story by Lindsey Doermann.

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References & Resources

InciWeb (2026) Morrill Fire. Accessed March 30, 2026.
National Interagency Fire Center (2026, March 27) National Fire News. Accessed March 30, 2026.
National Interagency Fire Center (2026, March 20) Fuels and Fire Behavior Advisory: Northern and Central Great Plains. Accessed March 30, 2026.
Nebraska Public Media (2026, March 30) ‘It’s like a death’: Grief, hope and resilience after fire ravages Nebraska Sandhills. Accessed March 30, 2026.
The Washington Post (2026, March 24) Wildfires rip through unusual parts of U.S., raising fears of a brutal season. Accessed March 30, 2026.

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Sendoff for Artemis II Crew

2026-03-30 18:18

NASA/Josh Valcarcel

From left to right, NASA astronauts Andre Douglas, Victor Glover, and Christina Koch, CSA (Canadian Space Agency) astronauts Jenni Gibbons, NASA astronaut Reid Wiseman, and CSA astronaut Jeremy Hansen pose for a photo before the Artemis II crew proceed to a media event on March 27, 2026. Douglas and Gibbons are the backup crew members for the mission; they would join the crew if a NASA or CSA astronaut, respectively, is unable to take part in the flight.

Artemis II is NASA’s first crewed mission under the Artemis program and will launch from the agency’s Kennedy Space Center in Florida. It will send Wiseman, Glover, Koch, and Hansen on an approximately 10-day journey around the Moon. Among other objectives, the agency will test the Orion spacecraft’s life support systems for the first time with people and lay the groundwork for future crewed Artemis missions.

Image credit: NASA/Josh Valcarcel

Seeing Blue During Schirmacher’s Summer Melt Season

2026-03-30 04:01

A network of cerulean blue meltwater drainage channels flowing across white and blue ice surfaces. An

Cerulean blue meltwater flows through drainage channels on the Nivlisen Ice Shelf, Antarctica, in this image acquired on January 6, 2026, by the OLI (Operational Land Imager) on Landsat 9.

NASA Earth Observatory/Michala Garrison

Summer is a busy season at Schirmacher Oasis, a rocky, ice-free plateau in Queen Maud Land, East Antarctica. Located near the grounding line of Nivlisen Ice Shelf and about 100 kilometers (60 miles) from the open waters of the Lazarev Sea, the “oasis” of land amid an otherwise continuous expanse of ice is home to dozens of small ice-covered freshwater lakes and two research stations.

It’s the season when all-white snow petrels are sometimes spotted soaring over the oasis, and fuzzy south polar skua and Wilson’s storm petrel chicks grow up in sheltered crevices on its cliffs and ridges. Under constant sunlight, the plateau’s freshwater lakes come to life, supporting cyanobacterial growth and teeming with microscopic tardigrades, rotifers, and nematodes. At times, groups of Adélie penguins toddle through the oasis and attempt to breed.

The summer months are also when temperatures creep just above freezing long enough for expansive networks of seasonal melt ponds and drainage channels on and within the surrounding ice to fill with bright blue meltwater that flows north onto and across the Nivlisen Ice Shelf. The satellite image above shows seasonal melt on January 6, 2026, during the peak of the 2026 melt season.

Schirmacher Oasis appears as a brown rocky plateau dotted with ice-covered lakes surrounded by fields of mostly white ice.

Lakes dot the rocky surface of Schirmacher Oasis in this image acquired on January 6, 2026, by the OLI on Landsat 9.

NASA Earth Observatory/Michala Garrison

The Nivlisen Ice Shelf is a floating tongue that forms as glacial ice flows off Antarctica and into the waters of the Lazarev Sea. The many blue ice areas found around the oasis are snow-free areas where old, compressed glacial ice with few air bubbles has been exposed by powerful katabatic winds and sublimation. This dense ice absorbs red wavelengths of light and reflects blue wavelengths, making it appear blue. Blue ice areas are rare in Antarctica, covering about 1 percent of the continent’s surface.

“The image captures the Nivlisen Ice Shelf during a phase of strong, system-wide hydrological connectivity,” said Geetha Priya Murugesan, a remote sensing scientist with the Centre for Incubation, Innovation, Research and Consultancy (CIIRC) and Jyothy Institute of Technology in Bengaluru, India. Such features aren’t always visible in optical satellite imagery, she added, noting that they are often frozen, buried under snow, or drained. “This image is notable because the ‘cerulean veins’ we see on the surface align with a deeper, persistent plumbing system that we monitor with radar.”

Drainage channels filled with blue meltwater zigzag across the white surfaces of Nivlisen Ice Shelf .

Surface drainage channels filled with meltwater flow across the Nivlisen Ice Shelf in this image acquired on January 6, 2026, by the OLI on Landsat 9.

NASA Earth Observatory/Michala Garrison

Murugesan and colleagues have analyzed decades of satellite data and conducted several years of field research in the area, including in 2026. Their work shows that since 2000, the surface melting caused by seasonal melt ponds and channels on the ice shelf has grown in depth, area, and volume. The depth and volume of melt features grew by a factor of 1.5, while their surface area increased by a factor of 1.2.

Murugesan thinks that the visibility of the drainage network in images like these hints at a deeper vulnerability of the ice shelf. The drainage channels trace preexisting structural weaknesses, including crevasses, that act as “hydraulic pathways” that concentrate meltwater in vulnerable zones near the grounding line, where it can weaken the ice shelf, Murugesan said.

The researchers have also linked peak melting periods like this one to atmospheric rivers and foehn winds that enhance surface melting and help route meltwater through the drainage networks. The dark color—low albedo—of the many blue ice areas surrounding the oasis contributes to drainage events by making ice surfaces less reflective, warmer, and thus more prone to summer melting, Murugesan added.

While Murugesan and colleagues are currently conducting a detailed analysis of the 2026 melt season to determine how it compares to past years, she said it appears to be a “strong melt event consistent with elevated melt conditions.”

NASA Earth Observatory images by Michala Garrison, using Landsat data from the U.S. Geological Survey. Story by Adam Voiland.