NASA to Support DARPA Robotic Satellite Servicing Program
2 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
Two robotic arms wrapped in gold material sitting on top of a black and silver box.
Naval Research Laboratory
NASA and the Defense Advanced Research Projects Agency (DARPA) have signed an interagency agreement to collaborate on a satellite servicing demonstration in geosynchronous Earth orbit, where hundreds of satellites provide communications, meteorological, national security, and other vital functions.
Under this agreement, NASA will provide subject matter expertise to DARPA’s Robotic Servicing of Geosynchronous Satellites (RSGS) program to help complete the technology development, integration, testing, and demonstration. The RSGS servicing spacecraft will advance in-orbit satellite inspection, repair, and upgrade capabilities.
NASA is excited to support our long-term partner and advance important technologies poised to benefit commercial, civil, and national objectives. Together, we will make meaningful, long-lasting contributions to the nation’s in-space servicing, assembly, and manufacturing (ISAM) capabilities.
Pam Melroy
NASA Deputy Administrator
NASA will use expertise from the agency’s On-orbit Servicing, Assembly, and Manufacturing 1 project and other relevant efforts to provide hands-on support to RSGS in the areas of space robotics, systems engineering, spacecraft subsystems, integration and testing, operator training, and spaceflight operations. NASA’s involvement in RSGS will continue advancing the agency’s understanding of and experience with complex ISAM systems.
DARPA will continue to lead the RSGS program, which has already achieved several important milestones, including the completion of two dexterous robotic arms designed for inspection and service that have been stress-tested for an on-orbit environment and the integration of those arms with their associated electronics, tools, and ancillary hardware to produce the fully integrated robotic payload.
NASA’s Hubble, MAVEN Help Solve the Mystery of Mars’ Escaping Water
NASA, ESA, STScI, John T. Clarke (Boston University); Processing: Joseph DePasquale (STScI)
Mars was once a very wet planet as is evident in its surface geological features. Scientists know that over the last 3 billion years, at least some water went deep underground, but what happened to the rest? Now, NASA’s Hubble Space Telescope and MAVEN (Mars Atmosphere and Volatile Evolution) missions are helping unlock that mystery.
“There are only two places water can go. It can freeze into the ground, or the water molecule can break into atoms, and the atoms can escape from the top of the atmosphere into space,” explained study leader John Clarke of the Center for Space Physics at Boston University in Massachusetts. “To understand how much water there was and what happened to it, we need to understand how the atoms escape into space.”
Clarke and his team combined data from Hubble and MAVEN to measure the number and current escape rate of the hydrogen atoms escaping into space. This information allowed them to extrapolate the escape rate backwards through time to understand the history of water on the Red Planet.
Escaping Hydrogen and “Heavy Hydrogen”
Water molecules in the Martian atmosphere are broken apart by sunlight into hydrogen and oxygen atoms. Specifically, the team measured hydrogen and deuterium, which is a hydrogen atom with a neutron in its nucleus. This neutron gives deuterium twice the mass of hydrogen. Because its mass is higher, deuterium escapes into space much more slowly than regular hydrogen.
Over time, as more hydrogen was lost than deuterium, the ratio of deuterium to hydrogen built up in the atmosphere. Measuring the ratio today gives scientists a clue to how much water was present during the warm, wet period on Mars. By studying how these atoms currently escape, they can understand the processes that determined the escape rates over the last four billion years and thereby extrapolate back in time.
Although most of the study’s data comes from the MAVEN spacecraft, MAVEN is not sensitive enough to see the deuterium emission at all times of the Martian year. Unlike the Earth, Mars swings far from the Sun in its elliptical orbit during the long Martian winter, and the deuterium emissions become faint. Clarke and his team needed the Hubble data to “fill in the blanks” and complete an annual cycle for three Martian years (each of which is 687 Earth days). Hubble also provided additional data going back to 1991 – prior to MAVEN’s arrival at Mars in 2014.
The combination of data between these missions provided the first holistic view of hydrogen atoms escaping Mars into space.
These are far-ultraviolet Hubble images of Mars near its farthest point from the Sun, called aphelion, on December 31, 2017 (top), and near its closest approach to the Sun, called perihelion, on December 19, 2016 (bottom). The atmosphere is clearly brighter and more extended when Mars is close to the Sun. Reflected sunlight from Mars at these wavelengths shows scattering by atmospheric molecules and haze, while the polar ice caps and some surface features are also visible. Hubble and MAVEN showed that Martian atmospheric conditions change very quickly. When Mars is close to the Sun, water molecules rise very rapidly through the atmosphere, breaking apart and releasing atoms at high altitudes.
NASA, ESA, STScI, John T. Clarke (Boston University); Processing: Joseph DePasquale (STScI)
“In recent years scientists have found that Mars has an annual cycle that is much more dynamic than people expected 10 or 15 years ago,” explained Clarke. “The whole atmosphere is very turbulent, heating up and cooling down on short timescales, even down to hours. The atmosphere expands and contracts as the brightness of the Sun at Mars varies by 40 percent over the course of a Martian year.”
The team discovered that the escape rates of hydrogen and deuterium change rapidly when Mars is close to the Sun. In the classical picture that scientists previously had, these atoms were thought to slowly diffuse upward through the atmosphere to a height where they could escape.
But that picture no longer accurately reflects the whole story, because now scientists know that atmospheric conditions change very quickly. When Mars is close to the Sun, the water molecules, which are the source of the hydrogen and deuterium, rise through the atmosphere very rapidly releasing atoms at high altitudes.
The second finding is that the changes in hydrogen and deuterium are so rapid that the atomic escape needs added energy to explain them. At the temperature of the upper atmosphere only a small fraction of the atoms have enough speed to escape the gravity of Mars. Faster (super-thermal) atoms are produced when something gives the atom a kick of extra energy. These events include collisions from solar wind protons entering the atmosphere or sunlight that drives chemical reactions in the upper atmosphere.
Mars was once a very wet planet. Scientists know that over the last 3 billion years, some of the water went underground, but what happened to the rest? Credit: NASA’s Goddard Space Flight Center; Lead Producer: Paul Morris; Mars Animations Producer: Dan Gallagher
Serving as a Proxy
Studying the history of water on Mars is fundamental not only to understanding planets in our own solar system but also the evolution of Earth-size planets around other stars. Astronomers are finding more and more of these planets, but they’re difficult to study in detail. Mars, Earth and Venus all sit in or near our solar system’s habitable zone, the region around a star where liquid water could pool on a rocky planet; yet all three planets have dramatically different present-day conditions. Along with its sister planets, Mars can help scientists grasp the nature of far-flung worlds across our galaxy.
The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, Colorado, also supports mission operations at Goddard. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
MAVEN’s principal investigator is based at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder. LASP is also responsible for managing science operations and public outreach and communications. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN mission. Lockheed Martin Space built the spacecraft and is responsible for MAVEN mission operations at Goddard. NASA’s Jet Propulsion Laboratory in Southern California provides navigation and Deep Space Network support. The MAVEN team is preparing to celebrate the spacecraft’s 10th year at Mars in September 2024.
Eclipses Create Atmospheric Gravity Waves, NASA Student Teams Confirm
4 Min Read
Eclipses Create Atmospheric Gravity Waves, NASA Student Teams Confirm
In this photo taken from the International Space Station, the Moon passes in front of the Sun casting its shadow, or umbra, and darkening a portion of the Earth’s surface above Texas during the annular solar eclipse Oct. 14, 2023.
Credits: NASA
Student teams from three U.S. universities became the first to measure what scientists have long predicted: eclipses can generate ripples in Earth’s atmosphere called atmospheric gravity waves. The waves’ telltale signature emerged in data captured during the North American annular solar eclipse on Oct. 14, 2023, as part of the Nationwide Eclipse Ballooning Project (NEBP) sponsored by NASA.
Through NEBP, high school and university student teams were stationed along the eclipse path through multiple U.S. states, where they released weather balloons carrying instrument packages designed to conduct engineering studies or atmospheric science experiments. A cluster of science teams located in New Mexico collected the data definitively linking the eclipse to the formation of atmospheric gravity waves, a finding that could lead to improved weather forecasting.
“Climate models are complicated, and they make some assumptions about what atmospheric factors to take into account.”
Angela Des Jardins
Director of the Montana Space Grant Consortium, which led NEBP.
“Understanding how the atmosphere reacts in the special case of eclipses helps us better understand the atmosphere, which in turn helps us make more accurate weather predictions and, ultimately, better understand climate change.”
Catching Waves in New Mexico
Previous ballooning teams also had hunted atmospheric gravity waves during earlier eclipses, research that was supported by NASA and the National Science Foundation. In 2019, an NEBP team stationed in Chile collected promising data, but hourly balloon releases didn’t provide quite enough detail. Attempts to repeat the experiment in 2020 were foiled by COVID-19 travel restrictions in Argentina and a heavy rainstorm that impeded data collection in Chile.
Project leaders factored in these lessons learned when planning for 2023, scheduling balloon releases every 15 minutes and carefully weighing locations with the best potential for success.
“New Mexico looked especially promising,” said Jie Gong, a researcher in the NASA Climate and Radiation Lab at the agency’s Goddard Space Flight Center in Greenbelt, Maryland, and co-investigator of the research on atmospheric gravity waves. “The majority of atmospheric gravity sources are convection, weather systems, and mountains. We wanted to eliminate all those possible sources.”
The project created a New Mexico “supersite” in the town of Moriarty where four atmospheric science teams were clustered: two from Plymouth State University in Plymouth, New Hampshire, and one each from the State University of New York (SUNY) Albany and SUNY Oswego.
Students began launching balloons at 10 a.m. the day before the eclipse.
“They worked in shifts through the day and night, and then everyone was on site for the eclipse,” said Eric Kelsey, research associate professor at Plymouth State and the NEBP northeast regional lead.
“Our hard work really paid off. The students had a real sense of accomplishment.”
Eric Kelsey
Research Associate Professor at Plymouth State and the NEBP Northeast Regional Lead.
Each balloon released by the science teams carried a radiosonde, an instrument package that measured temperature, location, humidity, wind direction, and wind speed during every second of its climb through the atmosphere. Radiosondes transmitted this stream of raw data to the team on the ground. Students uploaded the data to a shared server, where Gong and two graduate students spent months processing and analyzing it.
Confirmation that the eclipse had generated atmospheric gravity waves in the skies above New Mexico came in spring 2024.
“We put all the data together according to time, and when we plotted that time series, I could already see the stripes in the signal,” Gong said. “I bombarded everybody’s email. We were quite excited.”
Plymouth State University students Sarah Brigandi, left, and Sammantha Boulay release a weather balloon from Moriarty, New Mexico, to collect atmospheric data on Oct. 14, 2023.
NASA
For Students, Learning Curves Bring Opportunity
The program offered many students their first experience in collecting data. But the benefits go beyond technical and scientific skill.
“The students learned a ton through practicing launching weather balloons,” Kelsey said. “It was a huge learning curve. They had to work together to figure out all the logistics and troubleshoot. It’s good practice of teamwork skills.”
“All of this is technically complicated,” Des Jardins said. “While the focus now is on the science result, the most important part is that it was students who made this happen.”
NASA’s Science Mission Directorate Science Activation program funds NEBP, along with contributions from the National Space Grant College and Fellowship Project and support from NASA’s Balloon Program Office.
NASA Tunnel Generates Decades of Icy Aircraft Safety Data
5 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
A National Advisory Committee for Aeronautics researcher notes the conditions on the P-39L after its first test run in the Icing Research Tunnel on Sept. 13, 1944. The aircraft was too large to fit in the test section, so it was installed downstream in a larger area of the tunnel. The initial tests analyzed ice buildup on the nose, propeller blades, and antennae. In the summer of 1945, the P-39L was used to demonstrate the effectiveness of a thermal pneumatic boot ice-prevention system and heated propeller blades.
Credit: NASA
On Sept. 13, 1944, researchers subjected a Bell P-39L Airacobra to frigid temperatures and a freezing water spray in the National Advisory Committee for Aeronautics (NACA)’s new Icing Research Tunnel (IRT) to study inflight ice buildup. Since that first run at the Aircraft Engine Research Laboratory (now NASA’s Glenn Research Center) in Cleveland, the facility has operated on a regular basis for 80 years and remains the oldest and one of the largest icing tunnels in the world.
Water droplets in clouds can freeze on aircraft surfaces in certain atmospheric conditions. Ice buildup on the forward edges of wings and tails causes significant decreases in lift and rapid increases in drag. Ice can also block engine intakes and add weight. NASA has a long tradition of working to understand the conditions that cause icing and developing systems that prevent and remove ice buildup.
The NACA decided to build its new icing tunnel adjacent to the lab’s Altitude Wind Tunnel to take advantage of its powerful cooling equipment and unprecedented refrigeration system. The system, which can reduce air temperature to around –30 degrees Fahrenheit, produces realistic and repeatable icing conditions using a spray nozzle system that creates small, very cold droplets and a drive fan that generates airspeeds up to 374 miles per hour.
View upstream of the Icing Research Tunnel’s 25-foot-diameter drive fan in 1944. The original 12-bladed wooden fan and its 4,100-horsepower motor could produce air speeds up to 300 miles per hour. The motor and fan were replaced in 1987 and 1993, respectively.
Credit: NASA
Two rudimentary icing tunnels had briefly operated at the NACA’s Langley Memorial Aeronautical Laboratory in Hampton, Virginia, but icing research primarily relied on flight testing. The sophisticated new tunnel in Cleveland offered a safer way to study icing physics, test de-icing systems, and develop icing instrumentation.
During World War II, inlet icing was a key contributor to the heavy losses suffered by C-46s flying supply missions to allied troops in China. In February 1945, a large air scoop from the C-46 Commando was installed in the tunnel, where researchers determined the cause of the issue and redesigned the scoop to prevent freezing water droplets entering. The modifications were later incorporated into the C–46 and Convair C–40.
A National Advisory Committee for Aeronautics engineer experiments with an Icing Research Tunnel water spray system design in September 1949. Researchers used data taken from research flights to determine the proper droplet sizes. The atomizing spray system was perfected in 1950.
Credit: NASA
Despite these early successes, NACA engineers struggled to improve the facility’s droplet spray system because of a lack of small nozzles able to produce sufficiently small droplets. After years of dogged trial and error, the breakthrough came in 1950 with an 80-nozzle system that produced the uniform microscopic droplets needed to properly simulate a natural icing cloud.
Usage of the IRT increased in the 1950s, and the controlled conditions produced by the facility helped researchers define specific atmospheric conditions that produce icing. The Civil Aeronautics Authority (the precursor to the Federal Aviation Administration) used this data to establish regulations for all-weather aircraft. The facility also contributed to new icing protections for antennae and jet engines and the development of cyclical heating de-icing systems.
The success of the NACA’s icing program, along with the increased use of jet engines – which permitted cruising above the weather – reduced the need for additional icing research. In early 1957, just before the NACA transitioned to NASA, the center’s icing program was terminated. Nonetheless, the IRT remained active throughout the 1960s and 1970s supporting industry testing.
The Icing Research Tunnel is highlighted in this 1973 aerial photograph. The larger Altitude Wind Tunnel (AWT) is located behind it, and the Refrigeration Building that supported both tunnels is immediately to the left of the AWT.
Credit: NASA
By the mid-1970s, new icing issues were arising due to the increased use of helicopters, regional airliners, and general aviation aircraft. The center held an icing workshop in July 1978 where over 100 icing experts from across the world converged and lobbied for a reinstatement of NASA’s icing research program.
The agency agreed to provide funding to support a small team of researchers and increase operation of the icing facility. In 1982, a deadly icing-related airline crash spurred NASA to bring back a full-fledged icing research program.
Nearly all the tunnel’s major components were subsequently upgraded. Use of the IRT skyrocketed, and there was at least a one-year wait for new tests during this period. In 1988, the facility operated more hours than any year since 1950.
This model was installed in the Icing Research Tunnel in 2023 as part of the Advanced Air Mobility Rotor Icing Evaluation Study, which sought to refine testing of rotating models in the tunnel, validate 3D computational models, and study propeller icing issues.
Credit: NASA
The facility was used in a complementary way with the Twin Otter aircraft and computer simulation to improve de-icing systems, predictive tools, and instrumentation. IRT testing also accelerated the all-weather certification of the OH-60 Black Hawk helicopter. In the 1990s, the icing program turned its attention to combatting super-cooled large droplets, which can cause ice buildup in areas not protected by leading edge de-icing systems, and tailplane icing, which can cause commuter aircraft to pitch forward.
The IRT was one of the busiest facilities at the center in the 2000s and continues to maintain a steady test schedule today, investigating icing on turbofan engines and propellers, refining testing of rotating models, validating 3D models, and much more. The IRT been used to develop nearly every modern ice protection system, provided key icing environment data to regulatory agencies, and validated leading ice prediction software. After 80 years, it remains a critical tool for sustaining NASA’s leadership in the icing field.
Artemis IV: Gateway Gadget Fuels Deep Space Dining
2 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
A prototype of the Mini Potable Water Dispenser, currently in development at NASA’s Marshall Space Flight Center, is displayed alongside various food pouches during a demonstration at NASA’s Johnson Space Center.
NASA/David DeHoyos
NASA engineers are working hard to ensure no astronaut goes hungry on the Artemis IV mission.
When international teams of astronauts live on Gateway, humanity’s first space station to orbit the Moon, they’ll need innovative gadgets like the Mini Potable Water Dispenser. Vaguely resembling a toy water soaker, it manually dispenses water for hygiene bags, to rehydrate food, or simply to drink. It is designed to be compact, lightweight, portable and manual, making it ideal for Gateway’s relatively small size and remote location compared to the International Space Station closer to Earth.
The team at NASA’s Marshall Space Flight Center in Huntsville, Alabama leading the development of the dispenser understands that when it comes to deep space cuisine, the food astronauts eat is so much more than just fuel to keep them alive.
“Food doesn’t just provide body nourishment but also soul nourishment,” said Shaun Glasgow, project manager at Marshall. “So ultimately this device will help provide that little piece of soul nourishment. After a long day, the crew can float back and enjoy some pasta or scrambled eggs, a small sense of normalcy in a place far from home.”
As NASA continues to innovate and push the boundaries of deep space exploration, devices like the compact, lightweight dispenser demonstrate a blend of practicality and ingenuity that will help humanity chart its path to the Moon, Mars, and beyond.
An engineer demonstrates the use of the Mini Potable Water Dispenser by rehydrating a food pouch during a testing session at Johnson Space Center on June 6, 2024. This compact, lightweight dispenser is designed to help astronauts prepare meals in deep space.
NASA/David DeHoyos
A close-up view of the Mini Potable Water Dispenser prototype during a testing demonstration at NASA’s Johnson Space Center on June 6, 2024.
NASA/David DeHoyos
NASA food scientists rehydrate a food pouch during a test of the Mini Potable Water Dispenser at Johnson Space Center on June 6, 2024.
NASA/David DeHoyos
A NASA food scientist captures video of the Mini Potable Water Dispenser during testing at Johnson Space Center.
NASA/David DeHoyos
Matt Rowell, an engineer from the Marshall Space Flight Center demonstrates the Mini Potable Water Dispenser to NASA food scientists during a testing session.
NASA/David DeHoyos
Project manager Shaun Glasgow (right) demonstrates the Mini Potable Water Dispenser.
NASA/David DeHoyos
Brett Montoya, a lead space architect in the Center for Design and Space Architecture at Johnson Space Center, rehydrates a package of food using the Mini Potable Water Dispenser.
