NASA 3D Wind Measuring Laser Aims to Improve Forecasts from Air, Space

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Since last fall, NASA scientists have flown an advanced 3D Doppler wind lidar instrument across the United States to collect nearly 100 hours of data — including a flight through a hurricane. The goal? To demonstrate the unique capability of the Aerosol Wind Profiler (AWP) instrument to gather extremely precise measurements of wind direction, wind speed, and aerosol concentration – all crucial elements for accurate weather forecasting.Weather phenomena like severe thunderstorms and hurricanes develop rapidly, so improving predictions requires more accurate wind observations.
“There is a lack of global wind measurements above Earth’s surface,” explained Kris Bedka, the AWP principal investigator at NASA’s Langley Research Center in Hampton, Virginia. “Winds are measured by commercial aircraft as they fly to their destinations and by weather balloons launched up to twice per day from just 1,300 sites across the globe. From space, winds are estimated by tracking cloud and water vapor movement from satellite images.”
However, in areas without clouds or where water vapor patterns cannot be easily tracked, there are typically no reliable wind measurements. The AWP instrument seeks to fill these gaps with detailed 3D wind profiles.

Mounted to an aircraft with viewing ports underneath it, AWP emits 200 laser energy pulses per second that scatter and reflect off aerosol particles — such as pollution, dust, smoke, sea salt, and clouds — in the air. Aerosol and cloud particle movement causes the laser pulse wavelength to change, a concept known as the Doppler effect.
The AWP instrument sends these pulses in two directions, oriented 90 degrees apart from each other. Combined, they create a 3D profile of wind vectors, representing both wind speed and direction.

Kris bedka
NASA Research Physical Scientist

“The Aerosol Wind Profiler is able to measure wind speed and direction, but not just at one given point,” Bedka said. “Instead, we are measuring winds at different altitudes in the atmosphere simultaneously with extremely high detail and accuracy.”
Vectors help researchers and meteorologists understand the weather, so AWP’s measurements could significantly advance weather modeling and forecasting. For this reason, the instrument was chosen to be part of the National Oceanic and Atmospheric Administration’s (NOAA) Joint Venture Program, which seeks data from new technologies that can fill gaps in current weather forecasting systems. NASA’s Weather Program also saw mutual benefit in NOAA’s investments and provided additional support to increase the return on investment for both agencies.
On board NASA’s Gulfstream III (G-III) aircraft, AWP was paired with the agency’s High-Altitude Lidar Observatory (HALO) that measures water vapor, aerosols, and cloud properties through a combined differential absorption and high spectral resolution lidar.
Working together for the first time, AWP measured winds, HALO collected water vapor and aerosol data, and NOAA dropsondes (small instruments dropped from a tube in the bottom of the aircraft) gathered temperature, water vapor, and wind data.

“With our instrument package on board small, affordable-to-operate aircraft, we have a very powerful capability,” said Bedka. “The combination of AWP and HALO is NASA’s next-generation airborne weather remote sensing package, which we hope to also fly aboard satellites to benefit everyone across the globe.”

kris bedka
NASA Research Physical Scientist

The animation below, based on AWP data, shows the complexity and structure of aerosol layers present in the atmosphere. Current prediction models do not accurately simulate how aerosols are organized throughout the breadth of the atmosphere, said Bedka.

“When we took off on this particular day, I thought that we would be finding a clear atmosphere with little to no aerosol return because we were flying into what was the first real blast of cool Canadian air of the fall,” described Bedka. “What we found was quite the opposite: an aerosol-rich environment which provided excellent signal to accurately measure winds.” 
During the Joint Venture flights, Hurricane Helene was making landfall in Florida. The AWP crew of two pilots and five science team members quickly created a flight plan to gather wind measurements along the outer bands of the severe storm.

“A 3D wind profile can significantly improve weather forecasts, particularly for storms and hurricanes,” said Harshesh Patel, NOAA’s acting Joint Venture Program manager. “NASA Langley specializes in the development of coherent Doppler wind lidar technology and this AWP concept has potential to provide better performance for NOAA’s needs.”

The flights of the AWP lidar are serving as a proving ground for possible integration into a future satellite mission.
“The need to improve global 3D wind models requires a space-based platform,” added Patel. “Instruments like AWP have specific space-based applications that potentially align with NOAA’s mission to provide critical data for improving weather forecasting.”

After the NOAA flights, AWP and HALO were sent to central California for the Westcoast & Heartland Hyperspectral Microwave Sensor Intensive Experiment  and the Active Passive profiling Experiment, which was supported by NASA’s Planetary Boundary Layer Decadal Survey Incubation Program and NASA Weather Programs. These missions studied atmospheric processes within the planetary boundary layer, the lowest part of the atmosphere, that drives the weather conditions we experience on the ground. 

To learn more about lidar instruments at NASA visit:
NASA Langley Research Center: Generations of Lidar Expertise Läs mer…

Planetary Alignment Provides NASA Rare Opportunity to Study Uranus

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When a planet’s orbit brings it between Earth and a distant star, it’s more than just a cosmic game of hide and seek. It’s an opportunity for NASA to improve its understanding of that planet’s atmosphere and rings. Planetary scientists call it a stellar occultation and that’s exactly what happened with Uranus on April 7.Observing the alignment allows NASA scientists to measure the temperatures and composition of Uranus’ stratosphere – the middle layer of a planet’s atmosphere – and determine how it has changed over the last 30 years since Uranus’ last significant occultation.

“Uranus passed in front of a star that is about 400 light years from Earth,” said William Saunders, planetary scientist at NASA’s Langley Research Center in Hampton, Virginia, and science principal investigator and analysis lead, for what NASA’s team calls the Uranus Stellar Occultation Campaign 2025. “As Uranus began to occult the star, the planet’s atmosphere refracted the starlight, causing the star to appear to gradually dim before being blocked completely. The reverse happened at the end of the occultation, making what we call a light curve. By observing the occultation from many large telescopes, we are able to measure the light curve and determine Uranus’ atmospheric properties at many altitude layers.”  

William Saunders
Planetary Scientist at NASA’s Langley Research Center

This data mainly consists of temperature, density, and pressure of the stratosphere. Analyzing the data will help researchers understand how the middle atmosphere of Uranus works and could help enable future Uranus exploration efforts. 
To observe the rare event, which lasted about an hour and was only visible from Western North America, planetary scientists at NASA Langley led an international team of over 30 astronomers using 18 professional observatories.

“This was the first time we have collaborated on this scale for an occultation,” said Saunders. “I am extremely grateful to each member of the team and each observatory for taking part in this extraordinary event. NASA will use the observations of Uranus to determine how energy moves around the atmosphere and what causes the upper layers to be inexplicably hot. Others will use the data to measure Uranus’ rings, its atmospheric turbulence, and its precise orbit around the Sun.”
Knowing the location and orbit of Uranus is not as simple as it sounds. In 1986, NASA’s Voyager 2 spacecraft became the first and only spacecraft to fly past the planet – 10 years before the last bright stellar occultation occured in 1996. And, Uranus’ exact position in space is only accurate to within about 100 miles, which makes analyzing this new atmospheric data crucial to future NASA exploration of the ice giant.
These investigations were possible because the large number of partners provided many unique views of the stellar occultation from many different instruments.

Emma Dahl, a postdoctoral scholar at Caltech in Pasadena, California, assisted in gathering observations from NASA’s Infrared Telescope Facility (IRTF) on the summit of Mauna Kea in Hawaii – an observatory first built to support NASA’s Voyager missions.
“As scientists, we do our best work when we collaborate. This was a team effort between NASA scientists, academic researchers, and amateur astronomers,” said Dahl. “The atmospheres of the gas and ice giant planets [Jupiter, Saturn, Uranus, and Neptune] are exceptional atmospheric laboratories because they don’t have solid surfaces. This allows us to study cloud formation, storms, and wind patterns without the extra variables and effects a surface produces, which can complicate simulations very quickly.”
On November 12, 2024, NASA Langley researchers and collaborators were able to do a test run to prepare for the April occultation. Langley coordinated two telescopes in Japan and one in Thailand to observe a dimmer Uranus stellar occultation only visible from Asia. As a result, these observers learned how to calibrate their instruments to observe stellar occultations, and NASA was able to test its theory that multiple observatories working together could capture Uranus’ big event in April.
Researchers from the Paris Observatory and Space Science Institute, in contact with NASA, also coordinated observations of the November 2024 occultation from two telescopes in India. These observations of Uranus and its rings allowed the researchers, who were also members of the April 7 occultation team, to improve the predictions about the timing on April 7 down to the second and also improved modeling to update Uranus’ expected location during the occultation by 125 miles.

Uranus is almost 2 billion miles away from Earth and has an atmosphere composed of primarily hydrogen and helium. It does not have a solid surface, but rather a soft surface made of water, ammonia, and methane. It’s called an ice giant because its interior contains an abundance of these swirling fluids that have relatively low freezing points. And, while Saturn is the most well-known planet for having rings, Uranus has 13 known rings composed of ice and dust.
Over the next six years, Uranus will occult several dimmer stars. NASA hopes to gather airborne and possibly space-based measurements of the next bright Uranus occultation in 2031, which will be of an even brighter star than the one observed in April.

For more information on NASA’s Uranus Stellar Occultation Campaign 2025:
https://science.larc.nasa.gov/URANUS2025

Karen Fox / Molly WasserHeadquarters, Washington202-358-1600karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov 

Charles HatfieldLangley Research Center, Hampton, Virginia757-262-8289charles.g.hatfield@nasa.gov Läs mer…

NASA Tests Ultralight Antennas to Benefit Future National Airspace

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NASA engineers are using one of the world’s lightest solid materials to construct an antenna that could be embedded into the skin of an aircraft, creating a more aerodynamic and reliable communication solution for drones and other future air transportation options. 
Developed by NASA, this ultra-lightweight aerogel antenna is designed to enable satellite communications where power and space are limited. The aerogel is made up of flexible, high-performance plastics known as polymers. The design features high air content (95%) and offers a combination of light weight and strength. Researchers can adjust its properties to achieve either the flexibility of plastic wrap or the rigidity of plexiglass.
“By removing the liquid portion of a gel, you’re left with this incredibly porous structure,” said Stephanie Vivod, a chemical engineer at NASA’s Glenn Research Center in Cleveland. “If you’ve ever made Jell-O, you’ve performed chemistry that’s similar to the first step of making an aerogel.”
NASA sandwiched a layer of aerogel between a small circuit board and an array of thin, circular copper cells, then topped the design off with a type of film known for its electrical insulation properties. This innovation is known at NASA and in the aviation community as an active phased array aerogel antenna. 

In addition to decreasing drag by conforming to the shape of aircraft, aerogel antennas save weight and space and come with the ability to adjust their individual array elements to reduce signal interference. They are also less visually intrusive compared to other types of antennas, such as spikes and blades. The finished product looks like a honeycomb but lays flat on an aircraft’s surface.
In the summer of 2024, researchers tested a rigid version of the antenna on a Britten-Norman Defender aircraft during an in-flight demonstration with the U.S. Navy at Naval Air Station Patuxent River in Maryland.

Then, last October, researchers at NASA Glenn and the satellite communications firm Eutelsat America Corp., of Houston, began ground testing a version of the antenna mounted to a platform. The team successfully connected with a Eutelsat satellite in geostationary orbit, which bounced a signal back down to a satellite dish on a building at Glenn. Other demonstrations of the system at Glenn connected with a constellation of communications satellites operated in low Earth orbit by the data relay company Kepler. NASA researchers will design, build, and test a flexible version of the antenna later this year.
“This is significant because we are able to use the same antenna to connect with two very different satellite systems,” said Glenn researcher Bryan Schoenholz. Low Earth orbit satellites are relatively close – at 1,200 miles from the surface – and move quickly around the planet. Geostationary satellites are much farther – more than 22,000 miles from the surface – but orbit at speeds matching the Earth’s rotation, so they appear to remain in a fixed position above the equator.

The satellite testing was crucial for analyzing the aerogel antenna concept’s potential real-world applications. When modern aircraft communicate with stations on the ground, those signals are often transmitted through satellite relays, which can come with delays and loss of communication. This NASA-developed technology will make sure these satellite links are not disrupted during flight as the aerogel antenna’s beam is a concentrated flow of radio waves that can be electronically steered with precision to maintain the connection.
As new types of air transportation options are brought to the market and U.S airspace – from the small, piloted aircraft of today to the autonomous air taxis and delivery drones of tomorrow – these kinds of steady connections will become increasingly important. That’s why NASA’s Advanced Air Mobility mission and Transformative Aeronautics Concepts program are supporting research like the aerogel antennas that can boost industry efforts to safely expand the emerging marketplace for these transportation systems.
“If an autonomous air taxi or drone flight loses its communications link, we have a very unsafe situation,” Schoenholz said. “We can’t afford a ‘dropped call’ up there because that connection is critical to the safety of the flight.”
Schoenholz, Vivod, and others work on NASA’s Antenna Deployment and Optimization Technologies activity within the Transformational Tools and Technologies project. The activity aims to develop technologies that reduce the risk of radio frequency interference from air taxis, drones, commercial passenger jets, and other aircraft in increasingly crowded airspace. Läs mer…

NASA Studies Wind Effects and Aircraft Tracking with Joby Aircraft

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NASA engineers began using a network of ground sensors in March to collect data from an experimental air taxi to evaluate how to safely integrate such vehicles into airspace above cities – in all kinds of weather.
Researchers will use the campaign to help improve tools to assist with collision avoidance and landing operations and ensure safe and efficient air taxi operations in various weather conditions.
For years, NASA has looked at how wind shaped by terrain, including buildings in urban areas, can affect new types of aircraft. The latest test, which is gathering data from a Joby Aviation demonstrator aircraft, looks at another kind of wind – that which is generated by the aircraft themselves.
Joby flew its air taxi demonstrator over NASA’s ground sensor array near the agency’s Armstrong Flight Research Center in Edwards, California producing air flow data. The Joby aircraft has six rotors that allow for vertical takeoffs and landings, and tilt to provide lift in flight. Researchers focused on the air pushed by the propellers, which rolls into turbulent, circular patterns of wind.

This rolling wind can affect the aircraft’s performance, especially when it’s close to the ground, as well as others flying in the vicinity and people on the ground. Such wind turbulence is difficult to measure, so NASA enhanced its sensors with a new type of lidar – a system that uses lasers to measure precise distances – and that can map out the shapes of wind features.
“The design of this new type of aircraft, paired with the NASA lidar technology during this study, warrants a better understanding of possible wind and turbulence effects that can influence safe and efficient flights,” said Grady Koch, lead for this research effort, from NASA’s Langley Research Center in Hampton, Virginia.

NASA also set up a second array of ground nodes including radar, cameras, and microphones in the same location as the sensors to provide additional data on the aircraft. These nodes will collect tracking data during routine flights for several months.
The agency will use the data gathered from these ground nodes to demonstrate the tracking capabilities and functions of its “distributed sensing” technology, which involves embedding multiple sensors in an area where aircraft are operating.

This technology will be important for future air taxi flights, especially those occurring in cities by tracking aircraft moving through traffic corridors and around landing zones. Distributed sensing has the potential to enhance collision avoidance systems, air traffic management, ground-based landing sensors, and more.
“Our early work on a distributed network of sensors, and through this study, gives us the opportunity to test new technologies that can someday assist in airspace monitoring and collision avoidance above cities,” said George Gorospe, lead for this effort from NASA’s Ames Research Center in California’s Silicon Valley.
Using this data from an experimental air taxi aircraft, NASA will further develop the technology needed to help create safer air taxi flights in high-traffic areas. Both of these efforts will benefit the companies working to bring air taxis and drones safely into the airspace.
The work is led by NASA’s Transformational Tools and Technologies and Convergent Aeronautics Solutions projects under the Transformative Aeronautics Concepts program in support of NASA’s Advanced Air Mobility mission. NASA’s Advanced Air Mobility mission seeks to deliver data to guide the industry’s development of electric air taxis and drones. Läs mer…