Expedition 75 is Go for Tuesday Spacewalk to Install High-Speed Antenna
ESA astronaut Sophie Adenot is pictured inside the International Space Station’s Quest airlock with her helmet visor down as she nears the end of a six‑hour, 23‑minute spacewalk on Aug. 18. 2026.
NASA/Jack Hathaway
Two astronauts will exit the International Space Station on Tuesday and conduct a spacewalk to finish installing a high-speed space-to-ground antenna. The duo completed final spacewalk preparations on Monday with two of their Expedition 75 crewmates while the rest of the orbital residents studied the human respiratory system, activated Earth observation gear, and packed a cargo spacecraft prior to its departure.
Flight engineers Anil Menon of NASA and Sophie Adenot of ESA (European Space Agency) wrapped up their spacewalk preparations on Monday with tool configurations, spacesuit leak checks, and procedure reviews inside the Quest airlock. They are scheduled to set their spacesuits to battery power at 8:35 a.m. EDT on Tuesday signifying the start of a six-and-a-half-hour spacewalk to finish installing an antenna on the Z1 truss segment above the Unity module. NASA’s live spacewalk coverage will begin at 7 a.m.
NASA astronauts Jack Hathaway and Jessica Meir, flight engineer and station commander respectively, assisted Menon and Adenot with their spacewalk preparations throughout Monday. All four astronauts gathered together at the end of their shift for a conference with mission controllers on the ground to discuss spacewalk readiness and robotics operations.
On Tuesday, Hathaway will command the Canadarm2 robotic arm from inside the orbital outpost with Menon attached and guide him along the antenna installation worksite. Adenot will remain tethered to the Z1 where she and Menon will install the antenna and make the precise connections required to activate high‑speed transmissions with mission control. Meir will monitor the spacewalkers and work with Hathaway to help the spacewalkers in and out of their spacesuits.
Roscosmos flight engineers Pyotr Dubrov and Anna Kikina took turns at the beginning of their shift on Monday wearing an acoustic sensor around their necks that recorded their rapid exhalation rate. Doctors are exploring how microgravity affects air and fluid motion in the lungs. Afterward, Dubrov packed the Progress 94 resupply ship with trash and obsolete gear in advance of its departure in September. Kikina set up and activated Earth observation gear to automatically photograph islands and volcanoes throughout the Asia-Pacific region. Flight engineer Andrey Fedyaev programmed a different set of Earth observation hardware to capture multi-wavelength imagery of African lakes and the continent’s Atlantic coastline.
NASA Astronaut Reid Wiseman at Freedom 250 Grand Prix
NASA/Joel Kowsky
NASA astronaut and Artemis II commander Reid Wiseman is seen in the two-seat IndyCar as he prepares for driver Conor Daly to take him on a lap ahead of the start of the Freedom 250 Grand Prix, Sunday, Aug. 23, 2026, in Washington, D.C.
This roof-mounted air sensor in Addis Ababa, the capital of Ethiopia, is one of 10 used by NASA’s Multi-Angle Imager for Aerosols (MAIA) to study the city’s air quality. MAIA’s air sensors provide a detailed look at particulate matter that is 2.5 micrometers or less in diameter, also known as PM2.5, one of the world’s deadliest forms of air pollution.
Black carbon, or soot, is an important component of particulate pollution in Addis Ababa and is produced by diesel vehicles, fires, and other combustion sources. Detailed measurements from the MAIA air sensors reveal how pollution changes by time of day and season, including spikes produced by rush-hour traffic and holiday celebrations. The findings are relevant to cities around the world, including in the United States.
The 2025 State of Global Air Report, cited in the paper, estimates that these particles, some of which are tiny enough to enter the human bloodstream, are linked to around 4.9 million excess deaths per year globally. Of the many kinds of PM2.5, black carbon in particular has been linked to impacts on low birth weight, brain development, respiratory conditions, and premature mortality.
Mapping Air Pollution With MAIA Sensors in Addis Ababa
2 Min Read
Mapping Air Pollution With MAIA Sensors in Addis Ababa
PIA26694
Credits: NASA/JPL-Caltech
Downloads
Mapping Air Pollution With MAIA Sensors in Addis Ababa
PNG (456.55 KB)
Description
This map of Addis Ababa, the capital of Ethiopia, shows the locations of 10 air sensors that NASA’s Multi-Angle Imager for Aerosols (MAIA) mission is using to provide one of the most detailed looks ever at the city’s air pollution. Over the course of three years, these sensors measured particulate matter that is 2.5 micrometers or less in diameter, also known as PM2.5. Black carbon, or soot, is an important component of particulate pollution in Addis Ababa, which studies have linked to impacts on low birth weight, brain development, respiratory conditions, and premature mortality.
The color bar at right indicates air quality variations from 20 to 40 micrograms per cubic meter across the monitoring stations, with the darkest red being the poorest air quality.
In Ethiopia, black carbon is commonly produced by diesel vehicles, fires, and other combustion sources. Detailed measurements from the MAIA sensors reveal how Addis Ababa’s air pollution changes by time of day and season, including spikes produced by rush-hour traffic and holiday celebrations. The findings are relevant to cities around the world, including in the United States.
MAIA’s air pollution research is focused on a dozen regions around the globe, including three in the U.S. centered on Los Angeles, Atlanta, and Boston. The mission consists of a ground-based sensor network already in operation as well as a space observatory, which uses a camera built at NASA’s Jet Propulsion Laboratory, that will be launched by the Italian Space Agency (ASI) on an ASI satellite no earlier than late 2027. The camera is specially designed to help identify different types of PM2.5 aerosols based on how they reflect light, making it possible to map particle concentrations over each region that the mission studies.
The rugged terrain of the Silver Island Mountains and Crater Island rises above the pale playa and bright salt flats of former Lake Bonneville. The image was acquired with the OLI (Operational Land Imager) on Landsat 8 on June 4, 2026, and overlaid on a digital elevation model.
NASA Earth Observatory/Michala Garrison
At its peak, ancient Lake Bonneville would have been a sight to behold. Nearly as large as Lake Michigan, the Ice Age lake spread across much of western Utah and parts of Nevada and Idaho. When it eventually receded, it left behind flat, bright playas and salt flats rich with minerals—a landscape that would later serve as the setting for feats of engineering and technological ingenuity, as well as epic tales of exploration and desperation.
Lake Bonneville began forming about 55,000 years ago during a cool, wet period, when volcanic eruptions in what’s now southeastern Idaho diverted the Bear River, causing water to gather in Gem Valley and other basins to the south. For tens of thousands of years, a natural dam at Red Rock Pass helped confine the lake.
Then, about 18,000 years ago, water breached that dam, unleashing a torrent that entered the Columbia River system. Over a six-week period, amid one of North America’s largest floods, lake levels plummeted by more than 350 feet (105 meters). As the climate warmed and dried in subsequent millennia, the lake shrank dramatically, leaving remnants that include today’s Great Salt Lake, Utah Lake, and Sevier Lake.
Lake Bonneville may be gone, but its imprint on the region’s landscape remains—even in satellite imagery. In this image (below) captured by the OLI (Operational Land Imager) on the NASA-USGS Landsat 8 satellite, bathtub-like rings and wave-cut terraces trace the position of former shorelines. The dried lakebed—where fine-grained clay, marl, and sandy sediment settled out of the water—appears pale in comparison to the darker, rockier, more vegetated surroundings.
NASA scientists analyzed the terrain in this part of Utah when testing technologies that will be used on NASA’s DAVINCI mission to Venus. This image was acquired with the OLI (Operational Land Imager) on Landsat 8 on June 4, 2026.
NASA Earth Observatory/Michala Garrison
In deep parts of the basin, where runoff and groundwater still pool, bright deposits of evaporite minerals coat the land surfaces, forming salt flats. These remarkably flat surfaces are the product of water gradually evaporating and concentrating minerals to produce brines and hard mineral crusts, typically including halite and gypsum, along with potassium- and magnesium-bearing salts. Brines and deposits like these—particularly of potash, which is used as a fertilizer—have long made the playa a target for mining, as seen in the rectangular evaporation ponds above and below.
In contrast, the darker, more rugged terrain—including the Silver Island Mountains, the Newfoundland Mountains, and the Pilot Range—that rises above the playas is built from layers of erosion-resistant sedimentary and metasedimentary bedrock that is hundreds of millions of years old. These mountains also contain younger igneous and metamorphic rocks that formed when magma intruded into the ancient sedimentary sequence.
Crater Island, for instance, is composed of sedimentary rocks, including silica-rich sandstones and quartzites that formed as sands accumulated in a shallow ocean, as well as intrusions of quartz monzonite, granites, and other igneous rocks. Periods of crustal stretching later produced the fault-block mountains that define the landscape.
This animation shows the descent over Crater Island, Utah, of the camera system that will one day fly aboard NASA’s DAVINCI mission to Venus. It was created by stitching together 37 infrared images captured during a test on June 24, 2026.
Malin Space Science Systems/NASA/Jay Friedlander
Mapping geological distinctions like this took center stage in June 2026 when NASA scientists and engineers working with the agency’s DAVINCI mission came to Crater Island—a place they call “Venus on Earth”—to field-test the design of a set of cameras and a package of instruments that will eventually descend through the thick atmosphere of Venus and photograph mountains at scales finer than these Landsat images. During a 60-minute descent, the pioneering probe will capture near-infrared images, measure the atmospheric chemistry, and explore the environment of a world in unprecedented detail.
During the rehearsals at Crater Island, the camera system took hundreds of images of various rock formations, including iron-rich and silica-rich rock units, while suspended from a helicopter as it descended toward the surface. Using only the images acquired by DAVINCI’s camera systems, the team made three-dimensional maps of the area consistent with existing geologic maps, giving the scientists confidence that they will be able to map the geology of an analogous mountainous region on Venus that DAVINCI will study, an area called Alpha Regio.
Other epic adventures have played out on and around Lake Bonneville’s playas, as well. The flat, smooth surfaces have often been the setting for new land speed records. In 1960, Mickey Thompson became the first American to break the 400-miles-per-hour (640 kilometers-per-hour) barrier, hitting 406.60 miles per hour (654.36 kilometers per hour) in a streamlined race car on the Bonneville Salt Flats. The feat temporarily earned him the nickname “fastest man on Earth.”
People mine minerals from the Bonneville Salt Flats and use its flat surface to pursue land speed records. This image was acquired with the OLI (Operational Land Imager) on Landsat 8 on June 4, 2026.
NASA Earth Observatory/Michala Garrison
More recently, in August 2026, Andy Green, the first person to break the sound barrier on land, set a record for the fastest land speed in a hydrogen-fueled internal-combustion vehicle, reaching 406.320 miles per hour (653.909 kilometers per hour). By burning hydrogen rather than gasoline, the “rocket car” produced no carbon dioxide.
Nearly two centuries earlier, in August 1846, members of the ill-fated Donner-Reed Party also passed along the southern edge of Crater Island. As part of a shortcut toward Pilot Peak, they journeyed from Hastings Pass, past Floating Island, and toward Donner Spring. However, in an ominous sign of challenges to come, their heavy wagons broke through the thin salt crust and became mired in underlying mud, slowing them down and prompting them to abandon several wagons in the desert.
NASA Earth Observatory images by Michala Garrison, using Landsat data from the U.S. Geological Survey.Story by Adam Voiland.
