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By NASA
2 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
ResilienX employees Angelo Niforatos, left, and Ryan Pleskach, right, overview the NASA safety tools integrated into the company’s commercial system, July 11, 2025, at the ResilienX Headquarters in Syracuse, New York. Credit: ResilienX A future with advanced air mobility aircraft populating the skies will require the U.S. to implement enhanced preflight planning that can mitigate potential risks well before takeoff – and NASA is working to develop the tools to make that happen.
Preflight planning is critical to ensuring safety in the complex, high-risk environments of the future airspace. Timely, predictive, and up-to-date risk assessment within a single platform makes it much easier for drone or air taxi operators to check flight plans for high-risk concerns.
NASA is working on tools to deliver those services, and in June, the agency and aviation safety company ResilienX Inc. demonstrated how these tools can be integrated into commercial systems.
During a series of tests conducted at ResilienX’s facility in Syracuse, New York, researchers used NASA services that allowed flight operators to submit flight plans prior to departure, obtain risk assessment results, and then decide whether to proceed with flights or change their flight plans and re-assess risks. Allowing operators to perform these tasks quickly reduces the safety risk to flight passengers as well as humans on the ground.
The three NASA-developed services are intended to assess unique risks associated with highly automated aircraft flying at low altitudes over cities.
The partnership was managed under a Phase III NASA Small Business Innovation Research (SBIR) contract, which is an extension of prior work to assess weather-related risks. This collaboration is already leading to direct technology transfer of safety systems into ResilienX’s platform. The partnership is also intended to provide indirect benefits for ResilienX partners and customers, such as the U.S. Air Force and regional operators, helping to advance the overall safety of future airspace operations.
This work is led by NASA’s System-Wide Safety project under the Airspace Operations and Safety program in support of the agency’s Advanced Air Mobility mission. The mission seeks to deliver data, findings, and recommendations to guide the industry’s development of future air taxis and drones.
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Last Updated Aug 22, 2025 EditorDede DiniusContactTeresa Whitingteresa.whiting@nasa.gov Related Terms
Armstrong Flight Research Center Advanced Air Mobility Aeronautics Aeronautics Research Mission Directorate Airspace Operations and Safety Program Drones & You Small Business Innovation Research / Small Business System-Wide Safety Explore More
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By NASA
NASA/Nichole Ayers NASA astronaut Nichole Ayers took this photo of California’s San Francisco Bay Area surrounded by the cities of San Francisco, Oakland, and San Jose, and their suburbs on Aug. 3, 2025. At the time, the International Space Station orbited 260 miles above the Golden State.
The International Space Station serves as a unique platform for observing Earth with both hands-on and automated equipment. Station crew members have produced hundreds of thousands of images, recording phenomena such as storms in real time, observing natural events such as volcanic eruptions as they happen, and providing input to ground personnel for programming automated Earth-sensing systems.
In its third decade of continuous human presence, the space station has a far-reaching impact as a microgravity lab hosting technology, demonstrations, and scientific investigations from a range of fields. The research done on the orbiting laboratory will inform long-duration missions like Artemis and future human expeditions to Mars.
Learn more about Earth observation from the space station.
Image credit: NASA/Nichole Ayers
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By European Space Agency
Image: With the festive season approaching, even Earth-observing satellites are getting into the spirit, capturing a stunning compilation of European cities that resemble stars. View the full article
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By NASA
As any urban dweller who has lived through a heat wave knows, a shady tree can make all the difference. But what happens when there’s no shade available?
A recent study in Nature Communications used NASA satellite data to identify a major gap in global resilience to climate change: cities in the Global South have far less green space — and therefore less cooling capacity — than cities in the Global North. The terms Global North and Global South were used in the study to distinguish developed countries (mostly in the Northern Hemisphere) from developing nations (mostly in the Southern Hemisphere).
Cities tend to be hotter than nearby rural areas because of the urban heat island effect. Heat-trapping dark surfaces such as sidewalks, buildings, and roads absorb heat from the Sun’s rays, which raises the temperature of the city. Extreme heat poses serious health threats for urban residents, including dehydration, heat stroke, and even death. Though not a cure-all, greenery provides shade and releases moisture into the air, cooling the surroundings.
“Cities can strategically prioritize developing new green spaces in areas that have less green space,” said Christian Braneon, a climate scientist at NASA’s Goddard Institute for Space Studies in New York who was not affiliated with this study. “Satellite data can be really helpful for this.”
The Operational Land Imager (OLI) on the NASA and U.S. Geological Survey’s Landsat 8 satellite captured this natural color image of Sanaa, Yemen, on June 8, 2024. Sanaa, which has a hot, dry climate and little green space, had the second-lowest cooling capacity of 500 cities studied in a paper recently published in the journal Nature Communications. Wanmei Liang, NASA Earth Observatory An international team of researchers led by Yuxiang Li, a doctoral student at Nanjing University, analyzed the 500 largest cities in the world to compare their cooling capacities. They used data from the Landsat 8 satellite, jointly managed by NASA and the U.S. Geological Survey, to determine how effective green space was at cooling each city.
First, they calculated the average land surface temperature for the hottest month of 2018 for each city, as well as the average of the hottest months from 2017 to 2019. Next, the researchers used a metric called the Normalized Difference Vegetation Index (NDVI) to map how much green space each city had. The NDVI relies on the fact that healthy vegetation absorbs red light and reflects infrared light: the ratio of these wavelengths can show the density of healthy vegetation in a given satellite image.
Researchers found that cities in the Global South have just 70% of the greenery-related cooling capacity of cities in the Global North. The green spaces in an average Global South city cool the temperature by about 4.5 F (2.5 C). In an average Global North city, that cooling capacity is 6.5 F (3.6 C). This compounds an existing problem: cities in the South tend to be at lower latitudes (that is, nearer to the Equator), which are predicted to see more heat extremes in the coming years.
“It’s already clear that Global South countries will be impacted by heat waves, rising temperatures, and climatic extremes more than their Global North counterparts,” said Chi Xu, a professor of ecology at Nanjing University and a co-author of the study. The Global South has less capacity to adapt to heat because air conditioning is less common and power outages are more frequent.
Why do cities in the Global South struggle to stay cool? Cities in the Global South tend to have less green space than cities in the Global North. This mirrors studies of the disparities within cities, sometimes referred to as the “luxury effect”: wealthier neighborhoods tend to have more green space than poorer neighborhoods. “Wealthier cities also have more urban green spaces than the poorest cities,” Chi said.
It’s unlikely that urban planners can close the gap between the study’s worst-performing city (Mogadishu, Somalia) and the best-performing one (Charlotte, North Carolina).
Mogadishu is a dense city with a dry climate that limits vegetation growth. Still, there’s a lot that each city can learn from its neighbors. Within a given region, the researchers identified the city with the greatest cooling capacity and used that as a goal. They calculated the difference between the best-performing city in the region and every city nearby to get the potential additional cooling capacity. They found that cities’ average cooling capacity could be increased substantially — to as much as 18 F (10 C) — by systematically increasing green space quantity and quality.
“How you utilize green space is really going to vary depending on the climate and the urban environment you’re focused on,” said Braneon, whose research at NASA focuses on climate change and urban planning.
Greener cities in the U.S. and Canada have lower population densities. However, fewer people per square mile isn’t necessarily good for the environment: residents in low-density cities rely more on cars, and their houses tend to be bigger and less efficient. Braneon noted that there’s a suite of solutions beyond just planting trees or designating parks: Cities can increase cooling capacity by creating water bodies, seeding green roofs, and painting roofs or pavement lighter colors to reflect more light.
With a global study like this, urban planners can compare strategies for cities within the same region or with similar densities. “For newly urbanized areas that aren’t completely built out, there’s a lot of room to still change the design,” Braneon said.
By Madeleine Gregory
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Nov 26, 2024 Editor Rob Garner Contact Rob Garner rob.garner@nasa.gov Location Goddard Space Flight Center Related Terms
Climate Change Earth Goddard Institute for Space Studies Goddard Space Flight Center Landsat Landsat 8 / LDCM (Landsat Data Continuity Mission) View the full article
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By European Space Agency
Image: The landscape around the city of Bentiu in South Sudan is featured in this Copernicus Sentinel-2 image. View the full article
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