NASA’s Europa Clipper Solar Arrays Successfully Deploy at Kennedy Space Center
Technicians working inside the Payload Hazardous Servicing Facility at the agency’s Kennedy Space Center in Florida unfolded and fully extended the first of two five-panel solar arrays built for NASA’s Europa Clipper in preparation for inspection and cleaning as part of assembly, test, and launch operations.
On March 6, technicians working inside the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center in Florida unfolded and fully extended the first of two five-panel solar arrays for the agency’s Europa Clipper spacecraft. Each solar array measures 46.5 feet in length. For the operation, the team suspended the solar array on a gravity offload support system that helps support the weight of the solar array while it’s here on Earth. Up next, technicians will begin inspecting and cleaning as part of assembly, test, and launch operations. Planned to arrive at Jupiter in April 2030, the mission will study Jupiter’s moon Europa, which shows strong evidence beneath its icy crust of a global ocean over twice the volume of all Earth’s oceans. The spacecraft will ship to Florida later this year from NASA’s Jet Propulsion Lab in Southern California in preparation for launch aboard a SpaceX Falcon Heavy rocket from Kennedy’s Launch Complex 39A.
Zero-Boil-Off Tank Experiments to Enable Long-Duration Space Exploration
10 Min Read
Zero-Boil-Off Tank Experiments to Enable Long-Duration Space Exploration
Figure 1. The Gateway space station—humanity’s first space station around the Moon—will be capable of being refueled in space.
Credits: NASA
Do we have enough fuel to get to our destination? This is probably one of the first questions that comes to mind whenever your family gets ready to embark on a road trip. If the trip is long, you will need to visit gas stations along your route to refuel during your travel. NASA is grappling with similar issues as it gets ready to embark on a sustainable mission back to the Moon and plans future missions to Mars. But while your car’s fuel is gasoline, which can be safely and indefinitely stored as a liquid in the car’s gas tank, spacecraft fuels are volatile cryogenic liquid propellants that must be maintained at extremely low temperatures and guarded from environmental heat leaks into the spacecraft’s propellant tank. And while there is already an established network of commercial gas stations in place to make refueling your car a cinch, there are no cryogenic refueling stations or depots at the Moon or on the way to Mars. Furthermore, storing volatile propellant for a long time and transferring it from an in-space depot tank to a spacecraft’s fuel tank under microgravity conditions will not be easy since the underlying microgravity fluid physics affecting such operations is not well understood. Even with today’s technology, preserving cryogenic fuels in space beyond several days is not possible and tank-to-tank fuel transfer has never been previously performed or tested in space.
Heat conducted through support structures or from the radiative space environment can penetrate even the formidable Multi-Layer Insulation (MLI) systems of in-space propellant tanks, leading to boil-off or vaporization of the propellant and causing tank self-pressurization. The current practice is to guard against over-pressurizing the tank and endangering its structural integrity by venting the boil-off vapor into space. Onboard propellants are also used to cool down the hot transfer lines and the walls of an empty spacecraft tank before a fuel transfer and filling operation can take place. Thus, precious fuel is continuously wasted during both storage and transfer operations, rendering long-duration expeditions—especially a human Mars mission—infeasible using current passive propellant tank pressure control methods.
Zero-Boil-Off (ZBO) or Reduced Boil-Off (RBO) technologies provide an innovative and effective means to replace the current passive tank pressure control design. This method relies on a complex combination of active, gravity-dependent mixing and energy removal processes that allow maintenance of safe tank pressure with zero or significantly reduced fuel loss.
Zero Boil-off Storage and Transfer: A Transformative Space Technology
At the heart of the ZBO pressure control system are two proposed active mixing and cooling mechanisms to counter tank self-pressurization. The first is based on intermittent, forced, subcooled jet mixing of the propellantand involves complex, dynamic, gravity-dependent interaction between the jet and the ullage (vapor volume) to control the condensation and evaporation phase change at the liquid-vapor interface. The second mechanism uses subcooled droplet injection via a spraybar in the ullage to control tank pressure and temperature. While the latter option is promising and gaining prominence, it is more complex and has never been tested in microgravity where the phase change and transport behavior of droplet populations can be very different and nonintuitive compared to those on Earth.
Although the dynamic ZBO approach is technologically complex, it promises an impressive advantage over the currently used passive methods. An assessment of one nuclear propulsion concept for Mars transport estimated that the passive boil-off losses for a large liquid hydrogen tank carrying 38 tons of fuel for a three-year mission to Mars would be approximately 16 tons/year. The proposed ZBO system would provide a 42% saving of propellant mass per year. These numbers also imply that with a passive system, all the fuel carried for a three-year Mars mission would be lost to boil-off, rendering such a mission infeasible without resorting to the transformative ZBO technology.
The ZBO approach provides a promising method, but before such a complex technological and operational transformation can be fully developed, implemented, and demonstrated in space, important and decisive scientific questions that impact its engineering implementation and microgravity performance must be clarified and resolved.
The Zero-Boil-Off Tank (ZBOT) Microgravity Science Experiments
The Zero Boil-off Tank (ZBOT) Experiments are being undertaken to form a scientific foundation for the development of the transformative ZBO propellant preservation method. Following the recommendation of a ZBOT science review panel comprised of members from aerospace industries, academia, and NASA, it was decided to perform the proposed investigation as a series of three small-scale science experiments to be conducted onboard the International Space Station. The three experiments outlined below build upon each other to address key science questions related to ZBO cryogenic fluid management of propellants in space.
Figure 3. Astronaut Joseph M. Acaba installing ZBOT Hardware in the Microgravity Science Glovebox aboard the International Space Station.
Credit: NASA
The ZBOT-1 Experiment: Self-Pressurization & Jet Mixing
The first experiment in the series was carried out on the station in the 2017-2018 timeframe. Figure 3 shows the ZBOT-1 hardware in the Microgravity Science Glovebox (MSG) unit of the station. The main focus of this experiment was to investigate the self-pressurization and boiling that occurs in a sealed tank due to local and global heating, and the feasibility of tank pressure control via subcooled axial jet mixing. In this experiment, the complicated interaction of the jet flow with the ullage (vapor volume) in microgravity was carefully studied. Microgravity jet mixing data was also collected across a wide range of scaled flow and heat transfer parameters to characterize the time constants for tank pressure reduction, and the thresholds for geyser (liquid fountain) formation, including its stability, and penetration depth through the ullage volume. Along with very accurate pressure and local temperature sensor measurements, Particle Image Velocimetry (PIV) was performed to obtain whole-field flow velocity measurements to validate a Computational Fluid Dynamics (CFD) model.
Figure 4. Validation of ZBOT CFD Model Predictions for fluid flow and deformation of a spherical ullage in microgravity by a subcooled liquid jet mixing against ZBOT experimental results: (a) Model prediction of ullage position and deformation and flow vortex structures during subcooled jet mixing; (b) PIV image capture of flow vortex structures during jet mixing; (c) Ullage deformation captured by white light imaging; and (d) CFD model depiction of temperature contours during subcooled jet mixing. (ZBOT-1 Experiment, 2018)
Credit: Dr. Mohammad Kassemi, Case Western Reserve University
Some of the interesting findings of the ZBOT-1experiment are as follows:
Provided the first tank self-pressurization rate data in microgravity under controlled conditions that can be used for estimating the tank insulation requirements. Results also showed that classical self-pressurization is quite fragile in microgravity and nucleate boiling can occur at hotspots on the tank wall even at moderate heat fluxes that do not induce boiling on Earth.
Proved that ZBO pressure control is feasible and effective in microgravity using subcooled jet mixing, but also demonstrated that microgravity ullage-jet interaction does not follow the expected classical regime patterns (see Figure 4).
Enabled observation of unexpected cavitation during subcooled jet mixing, leading to massive phase change at both sides of the screened Liquid Acquisition Device (LAD) (see Figure 5). If this type of phase change occurs in a propellant tank, it can lead to vapor ingestion through the LAD and disruption of liquid flow in the transfer line, potentially leading to engine failure.
Developed a state-of-the-art two-phase CFD model validated by over 30 microgravity case studies (an example of which is shown in Figure 4). ZBOT CFD models are currently used as an effective tool for propellant tank scaleup design by several aerospace companies participating in the NASA tipping point opportunity and the NASA Human Landing System (HLS) program.
Figure 5. White light image captures of the intact single hemispherical ullage in ZBOT tank before depressurization by the subcooled jet (left) and after subcooled jet mixing pressure collapse that led to massive phase change bubble generation due to cavitation at the LAD (right). (ZBOT-1 Experiment, 2018).
Credit: Dr. Mohammad Kassemi, Case Western Reserve University
The ZBOT-NC Experiment: Non-Condensable Gas Effects
Non-condensable gases (NCGs) are used as pressurants to extract liquid for engine operations and tank-to-tank transfer. The second experiment, ZBOT-NC will investigate the effect of NCGs on the sealed tank self-pressurization and on pressure control by axial jet mixing. Two inert gases with quite different molecular sizes, Xenon, and Neon, will be used as the non-condensable pressurants. To achieve pressure control or reduction, vapor molecules must reach the liquid-vapor interface that is being cooled by the mixing jet and then cross the interface to the liquid side to condense.
This study will focus on how in microgravity the non-condensable gases can slow down or resist the transport of vapor molecules to the liquid-vapor interface (transport resistance) and will clarify to what extent they may form a barrier at the interface and impede the passage of the vapor molecules across the interface to the liquid side (kinetic resistance). By affecting the interface conditions, the NCGs can also change the flow and thermal structures in the liquid.
ZBOT-NC will use both local temperature sensor data and uniquely developed Quantum Dot Thermometry (QDT) diagnostics to collect nonintrusive whole-field temperature measurements to assess the effect of the non-condensable gases during both self-pressurization heating and jet mixing/cooling of the tank under weightlessness conditions. This experiment is scheduled to fly to the International Space Station in early 2025, and more than 300 different microgravity tests are planned. Results from these tests will also enable the ZBOT CFD model to be further developed and validated to include the non-condensable gas effects with physical and numerical fidelity.
The ZBOT-DP Experiment: Droplet Phase Change Effects
ZBO active pressure control can also be accomplished via injection of subcooled liquid droplets through an axial spray-bar directly into the ullage or vapor volume. This mechanism is very promising, but its performance has not yet been tested in microgravity. Evaporation of droplets consumes heat that is supplied by the hot vapor surrounding the droplets and produces vapor that is at a much lower saturation temperature. As a result, both the temperature and the pressure of the ullage vapor volume are reduced. Droplet injection can also be used to cool down the hot walls of an empty propellant tank before a tank-to-tank transfer or filling operation. Furthermore, droplets can be created during the propellant sloshing caused by acceleration of the spacecraft, and these droplets then undergo phase change and heat transfer. This heat transfer can cause a pressure collapse that may lead to cavitation or a massive liquid-to-vapor phase change. The behavior of droplet populations in microgravity will be drastically different compared to that on Earth.
The ZBOT-DP experiment will investigate the disintegration, coalescence (droplets merging together), phase change, and transport and trajectory characteristics of droplet populations and their effects on the tank pressure in microgravity. Particular attention will also be devoted to the interaction of the droplets with a heated tank wall, which can lead to flash evaporation subject to complications caused by the Liedenfrost effect (when liquid droplets propel away from a heated surface and thus cannot cool the tank wall). These complicated phenomena have not been scientifically examined in microgravity and must be resolved to assess the feasibility and performance of droplet injection as a pressure and temperature control mechanism in microgravity.
Back to Planet Earth
This NASA-sponsored fundamental research is now helping commercial providers of future landing systems for human explorers. Blue Origin and Lockheed Martin, participants in NASA’s Human Landing Systems program, are using data from the ZBOT experiments to inform future spacecraft designs.
Cryogenic fluid management and use of hydrogen as a fuel are not limited to space applications. Clean green energy provided by hydrogen may one day fuel airplanes, ships, and trucks on Earth, yielding enormous climate and economic benefits. By forming the scientific foundation of ZBO cryogenic fluid management for space exploration, the ZBOT science experiments and CFD model development will also help to reap the benefits of hydrogen as a fuel here on Earth.
PROJECT LEAD
Dr. Mohammad Kassemi (Dept Mechanical & Aerospace Engineering, Case Western Reserve University)
SPONSORING ORGANIZATION
Biological and Physical Sciences (BPS) Division, NASA Science Mission Directorate (SMD)
NASA’s Roman Team Selects Survey to Map Our Galaxy’s Far Side
The plane of our Milky Way galaxy, as seen by ESA’s Gaia space mission. It contains more than a billion stars, along with darker, dusty regions Gaia couldn’t see through. With its greater sensitivity and longer wavelength coverage, NASA’s Nancy Grace Roman Space Telescope’s galactic plane survey will peer through more of the dust and reveal far more stars.
Credit: ESA/Gaia/DPAC
NASA’s Nancy Grace Roman Space Telescope team has announced plans for an unprecedented survey of the plane of our Milky Way galaxy. It will peer deeper into this region than any other survey, mapping more of our galaxy’s stars than all previous observations combined.
“There’s a really broad range of science we can explore with this type of survey, from star formation and evolution to dust in between stars and the dynamics of the heart of the galaxy,” said Catherine Zucker, an astrophysicist at the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts, who co-authored a white paper describing some of the benefits of such an observing program.
Scientists have studied our solar system’s neighborhood pretty well, but much of the galaxy remains shrouded from view. NASA’s Nancy Grace Roman Space Telescope will peer through thick bands of dust to reveal parts of our galaxy we’ve never been able to explore before, thanks to a newly selected galactic plane survey. Credit: NASA’s Goddard Space Flight Center
A galactic plane survey was the top-ranked submission following a 2021 call for Roman survey ideas. Now, the scientific community will work together to design the observational program ahead of Roman’s launch by May 2027.
“There will be lots of trade-offs since scientists will have to choose between, for example, how much area to cover and how completely to map it in all the different possible filters,” said paper co-author Robert Benjamin, an astronomer at the University of Wisconsin-Whitewater.
While the details of the survey remain to be determined, scientists say if it covered about 1,000 square degrees – a region of sky as large as 5,000 full moons – it could reveal well over 100 billion cosmic objects (mainly stars).
“That would be pretty close to a complete census of all the stars in our galaxy, and it would only take around a month,” said Roberta Paladini, a senior research scientist at Caltech/IPAC in Pasadena, California, and the white paper’s lead author. “It would take decades to observe such a large patch of the sky with the Hubble or James Webb space telescopes. Roman will be a survey machine!”
Milky Way Anatomy
Observatories with smaller views of space have provided exquisite images of other galaxies, revealing complex structures. But studying our own galaxy’s anatomy is surprisingly difficult. The plane of the Milky Way covers such a large area on the sky that studying it in detail can take a very long time. Astronomers also must peer through thick dust that obscures distant starlight.
While we’ve studied our solar system’s neighborhood well, Zucker says, “we have a very incomplete view of what the other half of that Milky Way looks like beyond the galactic center.”
Observatories like NASA’s retired Spitzer Space Telescope have conducted large-area surveys of the galactic plane in longer wavelengths of light and revealed some star-forming regions on the far side of the galaxy. But it couldn’t resolve fine details like Roman will do.
“Spitzer set up the questions that Roman will be able to solve,” Benjamin said.
Roman’s combination of a large field of view, crisp resolution, and the ability to peer through dust make it the ideal instrument to study the Milky Way. And seeing stars in different wavelengths of light – optical and infrared – will help astronomers learn things such as the stars’ temperatures. That one piece of information unlocks much more data, from the star’s evolutionary stage and composition to its luminosity and size.
“We can do very detailed studies of things like star formation and the structure of our own galaxy in a way that we can’t do for any other galaxy,” Paladini said.
This image shows two views of the same spiral galaxy, called IC 5332, as seen by two NASA observatories – the James Webb Space Telescope’s observations appear at the top left and the Hubble Space Telescope’s at the bottom right. The views are mainly so different due to the wavelengths of light they each showcase. Hubble’s visible and ultraviolet observation features dark regions where dust absorbs those types of light. Webb sees longer wavelengths and detects that dust glowing in infrared. But neither could conduct an efficient survey of our Milky Way galaxy because it covers so much sky area; since IC 5332 is around 30 million light-years away, it appears as a small spot. It would take Hubble or Webb decades to survey the Milky Way, but NASA’s upcoming Nancy Grace Roman Space Telescope could do it in less than a month.
Credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), Rupali Chandar (UToledo), PHANGS Team
Roman will offer new insights about the structure of the central region known as the bulge, the “bar” that stretches across it, and the spiral arms that extend from it.
“We’ll basically rewrite the 3D picture of the far side of the galaxy,” Zucker said.
Roman’s sharp vision will help astronomers see individual stars even in stellar nurseries on the far side of the galaxy. That will help Roman generate a huge new catalog of stars since it will be able to map 10 times farther than previous precision mapping by ESA’s (the European Space Agency’s) Gaia space mission. Gaia mapped over 1 billion stars in 3D largely within about 10,000 light-years. Roman could map up to 100 billion stars 100,000 light-years away or more (stretching out to the most distant edge of our galaxy and beyond).
The Galactic Plane Survey is Roman’s first announced general astrophysics survey – one of several observation programs Roman will do in addition to its three core community surveys and Coronagraph technology demonstration. At least 25% of Roman’s five-year primary mission will be allocated to general astrophysics surveys in order to pursue science that can’t be done with only the mission’s core community survey data. Astronomers from all over the world will have the opportunity to use Roman and propose cutting-edge research, enabling the astronomical community to utilize the full potential of Roman’s capabilities to conduct extraordinary science.
The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA’s Jet Propulsion Laboratory and Caltech/IPAC in Southern California, the Space Telescope Science Institute in Baltimore, and a science team comprising scientists from various research institutions. The primary industrial partners are BAE Systems in Boulder, Colorado; L3Harris Technologies in Melbourne, Florida; and Teledyne Scientific & Imaging in Thousand Oaks, California.
Understanding Risk, Artificial Intelligence, and Improving Software Quality
The software discipline has broad involvement across each of the NASA Mission Directorates. Some recent discipline focus and development areas are highlighted below, along with a look at the Software Technical Discipline Team’s (TDT) approach to evolving discipline best practices toward the future.
Understanding Automation Risk
Software creates automation. Reliance on that automation is increasing the amount of software in NASA programs. This year, the software team examined historical software incidents in aerospace to characterize how, why, and where software or automation is mostly likely to fail. The goal is to better engineer software to minimize the risk of errors, improve software processes, and better architect software for resilience to errors (or improve fault-tolerance should errors occur).
Some key findings shown in the above charts, indicate that software more often does the wrong thing rather than just crash. Rebooting was found to be ineffective when software behaves erroneously. Unexpected behavior was mostly attributed to the code or logic itself, and about half of those instances were the result of missing software—software not present due to unanticipated situations or missing requirements. This may indicate that even fully tested software is exposed to this significant class of error. Data misconfiguration was a sizeable factor that continues to grow with the advent of more modern data-driven systems. A final subjective category assessed was “unknown unknowns”—things that could not have been reasonably anticipated. These accounted for 19% of software incidents studied.
The software team is using and sharing these findings to improve best practices. More emphasis is being placed on the importance of complete requirements, off-nominal test campaigns, and “test as you fly” using real hardware in the loop. When designing systems for fault tolerance, more consideration should be given to detecting and correcting for erroneous behavior versus just checking for a crash. Less confidence should be placed on rebooting as an effective recovery strategy. Backup strategies for automations should be employed for critical applications—considering the historic prevalence of absent software and unknown unknowns. More information can be found in NASA/TP-20230012154, Software Error Incident Categorizations in Aerospace.
Employing AI and Machine Learning Techniques
The rise of artificial intelligence (AI) and machine learning (ML) techniques has allowed NASA to examine data in new ways that were not previously possible. While NASA has been employing autonomy since its inception, AI/ML techniques provide teams the ability to expand the use of autonomy outside of previous bounds. The Agency has been working on AI ethics frameworks and examining standards, procedures, and practices, taking security implications into account. While AI/ML generally uses nondeterministic statistical algorithms that currently limit its use in safety-critical flight applications, it is used by NASA in more than 400 AI/ML projects aiding research and science. The Agency also uses AI/ML Communities of Practice for sharing knowledge across the centers. The TDT surveyed AI/ML work across the Agency and summarized it for trends and lessons.
Common usages of AI/ML include image recognition and identification. NASA Earth science missions use AI/ML to identify marine debris, measure cloud thickness, and identify wildfire smoke (examples are shown in the satellite images below). This reduces the workload on personnel. There are many applications of AI/ML being used to predict atmospheric physics. One example is hurricane track and intensity prediction. Another example is predicting planetary boundary layer thickness and comparing it against measurements, and those predictions are being fused with live data to improve the performance over previous boundary layer models.
Examples of how NASA uses AI/ML. Satellite images of clouds with estimation of cloud thickness (left) and wildfire detection (right).
NASA-HDBK-2203, NASA Software Engineering and Assurance Handbook (https://swehb.nasa.gov)
The Code Analysis Pipeline: Static Analysis Tool for IV&V and Software Quality Improvement
The Code Analysis Pipeline (CAP) is an open-source tool architecture that supports software development and assurance activities, improving overall software quality. The Independent Verification and Validation (IV&V) Program is using CAP to support software assurance on the Human Landing System, Gateway, Exploration Ground Systems, Orion, and Roman. CAP supports the configuration and automated execution of multiple static code analysis tools to identify potential code defects, generate code metrics that indicate potential areas of quality concern (e.g., cyclomatic complexity), and execute any other tool that analyzes or processes source code. The TDT is focused on integrating Modified Condition/Decision Coverage analysis support for coverage testing. Results from tools are consolidated into a central database and presented in context through a user interface that supports review, query, reporting, and analysis of results as the code matures.
The tool architecture is based on an industry standard DevOps approach for continuous building of source code and running of tools. CAP integrates with GitHub for source code control, uses Jenkins to support automation of analysis builds, and leverages Docker to create standard and custom build environments that support unique mission needs and use cases.
Improving Software Process & Sharing Best Practices
The TDT has captured the best practice knowledge from across the centers in NPR 7150.2, NASA Software Engineering Requirements, and NASA-HDBK-2203, NASA Software Engineering and Assurance Handbook (https://swehb.nasa.gov.) Two APPEL training classes have been developed and shared with several organizations to give them the foundations in the NPR and software engineering management. The TDT established several subteams to help programs/projects as they tackle software architecture, project management, requirements, cybersecurity, testing and verification, and programmable logic controllers. Many of these teams have developed guidance and best practices, which are documented in NASA-HDBK-2203 and on the NASA Engineering Network.
NPR 7150.2 and the handbook outline best practices over the full lifecycle for all NASA software. This includes requirements development, architecture, design, implementation, and verification. Also covered, and equally important, are the supporting activities/functions that improve quality, including software assurance, safety configuration management, reuse, and software acquisition. Rationale and guidance for the requirements are addressed in the handbook that is internally and externally accessible and regularly updated as new information, tools, and techniques are found and used.
The Software TDT deputies train software engineers, systems engineers, chief engineers, and project managers on the NPR requirements and their role in ensuring these requirements are implemented across NASA centers. Additionally, the TDT deputies train software technical leads on many of the advanced management aspects of a software engineering effort, including planning, cost estimating, negotiating, and handling change management.
Splashdown! NASA’s SpaceX Crew-7 Finishes Mission, Returns to Earth
Roscosmos cosmonaut Konstantin Borisov, left, ESA (European Space Agency) astronaut Andreas Mogensen, NASA astronaut Jasmin Moghbeli, and Japan Aerospace Exploration Agency (JAXA) astronaut Satoshi Furukawa are seen inside the SpaceX Dragon Endurance spacecraft onboard the SpaceX recovery ship MEGAN shortly after having landed in the Gulf of Mexico off the coast of Pensacola, Florida, Tuesday, March 12, 2024. Moghbeli, Mogensen, Furukawa, and Borisov are returning after nearly six-months in space as part of Expedition 70 aboard the International Space Station.
NASA/Joel Kowsky
NASA’s SpaceX Crew-7 completed the agency’s seventh commercial crew rotation mission to the International Space Station on Tuesday after splashing down safely in a Dragon spacecraft off the coast of Pensacola, Florida. The international crew of four spent 199 days in orbit.
NASA astronaut Jasmin Moghbeli, ESA (European Space Agency) astronaut Andreas Mogensen, JAXA (Japan Aerospace Exploration Agency) astronaut Satoshi Furukawa, and Roscosmos cosmonaut Konstantin Borisov, returned to Earth splashing down at 5:47 a.m. EDT. Teams aboard SpaceX recovery vessels retrieved the spacecraft and its crew. After returning to shore, the crew will fly to NASA’s Johnson Space Center in Houston.
“After more than six months aboard the International Space Station, NASA’s SpaceX Crew-7 has safely returned home,” said NASA Administrator Bill Nelson. “This international crew showed that space unites us all. It’s clear that we can do more – we can learn more – when we work together. The science experiments conducted during their time in space will help prepare for NASA’s bold missions at the Moon, Mars, and beyond, all while benefitting humanity here on Earth.”
The Crew-7 mission lifted off at 3:27 a.m. Aug. 26, 2023, on a Falcon 9 rocket from NASA’s Kennedy Space Center in Florida. About 30 hours later, Dragon docked to the Harmony module’s space-facing port. Crew-7 undocked at 11:20 a.m. Monday, March 11, to begin the trip home.
Moghbeli, Mogensen, Furukawa, and Borisov traveled 84,434,094 miles during their mission, spent 197 days aboard the space station, and completed 3,184 orbits around Earth. The Crew-7 mission was the first spaceflight for Moghbeli and Borisov. Mogensen has logged 209 days in space over his two flights, and Furukawa has logged 366 days in space over his two flights.
Throughout their mission, the Crew-7 members contributed to a host of science and maintenance activities and technology demonstrations. Moghbeli conducted one spacewalk, joined by NASA astronaut Loral O’Hara, replacing one of the 12 trundle bearing assemblies on the port solar alpha rotary joint, which allows the arrays to track the Sun and generate electricity to power the station.
The crew contributed to hundreds of experiments and technology demonstrations, including the first study of human response to different spaceflight durations, and an experiment growing food on the space station.
This was the third flight of the Dragon spacecraft, named Endurance. It also previously supported the Crew-3 and Crew-5 missions. The spacecraft will return to Florida for inspection and processing at SpaceX’s refurbishing facility at Cape Canaveral Space Force Station, where teams will inspect the Dragon, analyze data on its performance, and process it for its next flight.
The Crew-7 flight is part of NASA’s Commercial Crew Program and its return to Earth follows on the heels of NASA’s SpaceX Crew-8 launch, which docked to the station March 5, beginning another science expedition.
The goal of NASA’s Commercial Crew Program is safe, reliable, and cost-effective transportation to and from the International Space Station and low Earth orbit. This already is providing additional research time and has increased the opportunity for discovery aboard humanity’s microgravity testbed for exploration, including helping NASA prepare for human exploration of the Moon and Mars.
Learn more about NASA’s Commercial Crew program at:
