Jump to content

Recommended Posts

  • Publishers
Posted

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

risks concept
Risks Concept

Risk is inherent in human spaceflight. However, specific risks can and should be understood, managed, and mitigated to reduce threats posed to astronauts. Risk management in the context of human spaceflight can be viewed as a trade-based system. The relevant evidence in life sciences, medicine, and engineering is tracked and evaluated to identify ways to minimize overall risk to the astronauts and to ensure mission success. The Human System Risk Board (HSRB) manages the process by which scientific evidence is utilized to establish and reassess the postures of the various risks to the Human System during all of the various types of existing or anticipated crewed missions. The HSRB operates as part of the Health and Medical Technical Authority of the Office of the Chief Health and Medical Officer of NASA via the JSC Chief Medical Officer.

The HSRB approaches to human system risks is analogous to the approach the engineering profession takes with its Failure Mode and Effects Analysis in that a process is utilized to identify and address potential problems, or failures to reduce their likelihood and severity. In the context of risks to the human system, the HSRB considers eight missions which different in their destinations and durations (known as Design Reference Missions [DRM]) to further refine the context of the risks. With each DRM a likelihood and consequence are assigned to each risk which is adjusted scientific evidence is accumulated and understanding of the risk is enhanced, and mitigations become available or are advanced.

This framework enables the principles of Continuous Risk Management and Risk Informed Decision Making (RIDM) to be applied in an ongoing fashion to the challenges posed by Human System Risks. Using this framework consistently across the 29 risks allows management to see where risks need additional research or technology development to be mitigated or monitored and for the identification of new risks and concerns. Further information on the implementation of the risk management process can be found in the following documents:

Human System Risk Board Management Office

The HSRB Risk Management Office governs the execution of the Human System Risk management process in support of the HSRB. It is led by the HSRB Chair, who is also referred to as the Risk Manager.

Risk Custodian Teams

Along with the Human System Risk Manager, a team of risk custodians (a researcher, an operational researcher or physician, and an epidemiologist, who each have specific expertise) works together to understand and synthesize scientific and operational evidence in the context of spaceflight, identify and evaluate metrics for each risk in order to communicate the risk posture to the agency.

Directed Acyclic Graphs 

Summary

The HSRB uses Directed Acyclic Graphs (DAG), a type of causal diagramming, as visual tools to create a shared understanding of the risks, improve communication among those stakeholders, and enable the creation of a composite risk network that is vetted by members of the NASA community and configuration managed (Antonsen et al., NASA/TM– 20220006812). The knowledge captured is the Human Health and Performance community’s knowledge about the causal flow of a human system risk, and the relationships that exist between the contributing factors to that risk.

DAGs are:

  • Intended to improve communication between:
    • Managers and subject matter experts who need to discuss human system risks
    • Subject matter experts in different disciplines where human system risks interact with one another in a potentially cumulative fashion
  • Visual representations of known or suspected relationships
  • Directed – the relationship flows in one direction between any two nodes
  • Acyclic – cycles in the graph are not allowed
Example of a Directed Acyclic Graph
Example of a Directed Acyclic Graph. This is a simplified illustration of how and the individual, the crew, and the system contribute to the likelihood of successful task performance in a mission. Individual readiness is affected by many of the health and performance-oriented risks followed by the HSRB, but the readiness of any individual crew is complemented by the team and the system that the crew works within. Failures of task performance may lead to loss of mission objectives if severe.
NASA
View Larger (Example of a Directed Acyclic Graph) Image

Details

At NASA, the Human System Risks have historically been conceptualized as deriving from five Hazards present in the spaceflight environment. These are: altered gravity, isolation and confinement, radiation, a hostile closed environment, and distance from Earth. These Hazards are aspects of the spaceflight environment that are encountered when someone is launched into space and therefore are the starting point for causal diagramming of spaceflight-related risk issues for the HSRB.

These Hazards are often interpreted in relation to physiologic changes that occur in humans as a result of the exposure; however, interaction between human crew (behavioral health and performance), which may be degraded due to the spaceflight environment – and the vehicle and mission systems that the crew must operate – can also be influenced by these Hazards.

Each Human System Risk DAG is intended to show the causal flow of risk from Hazards to Mission Level Outcomes. As such, the structure of each DAG starts with at least one Hazard and ends with at least one of the pre-defined Mission Level Outcomes. In between are the nodes and edges of the causal flow diagrams that are relevant to the Risk under consideration. These are called ‘contributing factors’ in the HSRB terminology, and include countermeasures, medical conditions, and other Human System Risks. A graph data structure is composed of a set of vertices (nodes), and a set of edges (links). Each edge represents a relationship between two nodes. There can be two types of relationships between nodes: directed and undirected. For example, if an edge exists between two nodes A and B and the edge is undirected, it is represented as A–B, (no arrow). If the edge were directed, for example from A to B, then this is represented with an arrow (A->B). Each directed arrow connecting one node to another on a DAG indicates a claim of causality. A directed graph can potentially contain a cycle, meaning that, from a specific node, there exists a path that would eventually return to that node. A directed graph that has no cycles is known as acyclic. Thus, a graph with directed links and no cycles is a DAG.  DAGs are a type of network diagram that represent causality in a visual format.

DAGs are updated with the regular Human System Risk updates generally every 1-2 years. Approved DAGs can be found in the NASA/TP 20220015709 below or broken down under each Human System Risk.

Documents

Points of Contact

Mary Van Baalen
Dan Buckland
Bob Scully
Kim Lowe

Share

Details

Last Updated
Mar 11, 2025
Editor
Robert E. Lewis

View the full article

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Topics

    • By NASA
      Explore This Section Perseverance Home Mission Overview Rover Components Mars Rock Samples Where is Perseverance? Ingenuity Mars Helicopter Mission Updates Science Overview Objectives Instruments Highlights Exploration Goals News and Features Multimedia Perseverance Raw Images Images Videos Audio More Resources Mars Missions Mars Sample Return Mars Perseverance Rover Mars Curiosity Rover MAVEN Mars Reconnaissance Orbiter Mars Odyssey More Mars Missions Mars Home 3 min read
      Visiting Mars on the Way to the Outer Solar System
      Written by Roger Wiens, Principal Investigator, SuperCam instrument / Co-Investigator, SHERLOC instrument at Purdue University
      A portion of the “Sally’s Cove” outcrop where the Perseverance rover has been exploring. The radiating lines in the rock on the left of the image may indicate that it is a shatter cone, showing the effects of the shock wave from a nearby large impact. The image was taken by Mastcam-Z’s left camera on March 21, 2025 (Sol 1452, or Martian day 1,452 of the Mars 2020 mission) at the local mean solar time of 12:13:44. Mastcam-Z is a pair of cameras located high on the rover’s mast. This image was voted by the public as “Image of the week.” NASA/JPL-Caltech/ASU Recently Mars has had a few Earthly visitors. On March 1, NASA’s Europa Clipper flew within 550 miles (884 kilometers) of the Red Planet’s surface on its way out to Jupiter. On March 12, the European Space Agency’s Hera spacecraft flew within about 3,100 miles (5,000 kilometers) of Mars, and only 300 kilometers from its moon, Deimos. Hera is on its way to study the binary asteroid Didymos and its moon Dimorphos. Next year, in May 2026, NASA’s Psyche mission is scheduled to buzz the Red Planet on its way to the metal-rich asteroid 16 Psyche, coming within a few thousand kilometers.
      Why all these visits to Mars? You might at first think that they’re using Mars as an object of opportunity for their cameras, and you would be partially right. But Mars has more to give these missions than that. The main reason for these flybys is the extra speed that Mars’ velocity around the Sun can give them. The idea that visiting a planet can speed up a spacecraft is not all that obvious, because the same gravity that attracts the spacecraft on its way towards the planet will exert a backwards force as the spacecraft leaves the planet.
      The key is in the direction that it approaches and leaves the planet. If the spacecraft leaves Mars heading in the direction that Mars is traveling around the Sun, it will gain speed in that direction, slingshotting it farther into the outer solar system. A spacecraft can typically gain several percent of its speed by performing such a slingshot flyby. The closer it gets to the planet, the bigger the effect. However, no mission wants to be slowed by the upper atmosphere, so several hundred kilometers is the closest that a mission should go. And the proximity to the planet is also affected by the exact direction the spacecraft needs to go when it leaves Mars.
      Clipper’s Mars flyby was a slight exception, slowing down the craft — by about 1.2 miles per second (2 kilometers per second) — to steer it toward Earth for a second gravity assist in December 2026. That will push the spacecraft the rest of the way to Jupiter, for its 2030 arrival.
      While observing Mars is not the main reason for their visits, many of the visiting spacecraft take the opportunity to use their cameras either to perform calibrations or to study the Red Planet and its moons.
      During Clipper’s flyby over sols 1431-1432, Mastcam-Z was directed to watch the skies for signs of the interplanetary visitor. Clipper’s relatively large solar panels could have reflected enough sunlight for it to be seen in the Mars night sky, much as we can see satellites overhead from Earth. Unfortunately, the spacecraft entered the shadow of Mars just before it came into potential view above the horizon from Perseverance’s vantage point, so the sighting did not happen. But it was worth a try.
      Meanwhile, back on the ground, Perseverance is performing something of a cliff-hanger. “Sally’s Cove” is a relatively steep rock outcrop in the outer portion of Jezero crater’s rim just north of “Broom Hill.” Perseverance made an approach during March 19-23, and has been exploring some dark-colored rocks along this outcrop, leaving the spherules behind for the moment. Who knows what Perseverance will find next?
      Share








      Details
      Last Updated Mar 28, 2025 Related Terms
      Blogs Explore More
      2 min read Sols 4493-4494: Just Looking Around


      Article


      4 hours ago
      2 min read Sols 4491-4492: Classic Field Geology Pose


      Article


      2 days ago
      3 min read Sols 4488-4490: Progress Through the Ankle-Breaking Terrain (West of Texoli Butte, Climbing Southward)


      Article


      4 days ago
      Keep Exploring Discover More Topics From NASA
      Mars


      Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited…


      All Mars Resources


      Explore this collection of Mars images, videos, resources, PDFs, and toolkits. Discover valuable content designed to inform, educate, and inspire,…


      Rover Basics


      Each robotic explorer sent to the Red Planet has its own unique capabilities driven by science. Many attributes of a…


      Mars Exploration: Science Goals


      The key to understanding the past, present or future potential for life on Mars can be found in NASA’s four…

      View the full article
    • By NASA
      5 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      Advanced Capabilities for Emergency Response Operations (ACERO) researchers Lynne Martin, left, and Connie Brasil use the Portable Airspace Management System (PAMS) to view a simulated fire zone and set a drone flight plan during a flight test the week of March 17, 2025.NASA/Brandon Torres-Navarrete NASA researchers conducted initial validation of a new airspace management system designed to enable crews to use aircraft fight and monitor wildland fires 24 hours a day, even during low-visibility conditions.  
      From March 17-28, NASA’s Advanced Capabilities for Emergency Response Operations (ACERO) project stationed researchers at multiple strategic locations across the foothills of the Sierra de Salinas mountains in Monterey County, California. Their mission: to test and validate a new, portable system that can provide reliable airspace management under poor visual conditions, one of the biggest barriers for aerial wildland firefighting support. 
      The mission was a success. 
      “At NASA, we have decades of experience leveraging our aviation expertise in ways that improve everyday life for Americans,” said Carol Carroll, deputy associate administrator for NASA’s Aeronautics Research Mission Directorate at agency headquarters in Washington. “We need every advantage possible when it comes to saving lives and property when wildfires affect our communities, and ACERO technology will give responders critical new tools to monitor and fight fires.” 
      NASA ACERO researchers Samuel Zuniga,left, and Jonathan La Plain prepare for a drone flight test using the PAMS in Salinas on March 19, 2025.NASA/Brandon Torres-Navarrete One of the barriers for continued monitoring, suppression, and logistics support in wildland fire situations is a lack of tools for managing airspace and air traffic that can support operations under all visibility conditions. Current aerial firefighting operations are limited to times with clear visibility when a Tactical Air Group Supervisor or “air boss” in a piloted aircraft can provide direction. Otherwise, pilots may risk collisions. 
      The ACERO technology will provide that air boss capability for remotely piloted aircraft operations – and users will be able to do it from the ground. The project’s Portable Airspace Management System (PAMS) is a suitcase-sized solution that builds on decades of NASA air traffic and airspace management research. The PAMS units will allow pilots to view the locations and operational intents of other aircraft, even in thick smoke or at night. 
      During the testing in Salinas, researchers evaluated the PAMS’ core airspace management functions, including strategic coordination and the ability to automatically alert pilots once their aircrafts exit their preapproved paths or the simulated preapproved fire operation zone.  
      Using the PAMS prototype, researchers were able to safely conduct  flight operations of a vertical takeoff and landing aircraft operated by Overwatch Aero, LLC, of Solvang, California, and two small NASA drones. 
      Flying as if responding to a wildfire scenario, the Overwatch aircraft connected with two PAMS units in different locations. Though the systems were separated by mountains and valleys with weak cellular service, the PAMS units were able to successfully share and display a simulated fire zone, aircraft location, flight plans, and flight intent, thanks to a radio communications relay established by the Overwatch aircraft.  
      Operating in a rural mountain range validated that PAMS could work successfully in an actual wildland fire environment.   
      “Testing in real mountainous environments presents numerous challenges, but it offers significantly more value than lab-based testing,” said Dr. Min Xue, ACERO project manager at NASA’s Ames Research Center in California’s Silicon Valley. “The tests were successful, providing valuable insights and highlighting areas for future improvement.”
      NASA ACERO researchers fly a drone to test the PAMS during a flight test on March 19, 2025.NASA/Brandon Torres-Navarrete Pilots on the ground used PAMS to coordinate the drones, which performed flights simulating aerial ignition – the practice of setting controlled, intentional fires to manage vegetation, helping to control fires and reduce wildland fire risk. 
      As a part of the testing, Joby Aviation of Santa Cruz, California, flew its remotely piloted aircraft, similar in size to a Cessna Grand Caravan, over the testing site. The PAMS system successfully exchanged aircraft location and flight intent with Joby’s mission management system. The test marked the first successful interaction between PAMS and an optionally piloted aircraft. 
      Fire chiefs from the California Department of Forestry and Fire Protection (CAL FIRE) attended the testing and provided feedback on the system’s functionality, features that could improve wildland fire air traffic coordination, and potential for integration into operations. 
      “We appreciate the work being done by the NASA ACERO program in relation to portable airspace management capabilities,” said Marcus Hernandez, deputy chief for CAL FIRE’s Office of Wildfire Technology. “It’s great to see federal, state, and local agencies, as it is important to address safety and regulatory challenges alongside technological advancements.” 
      ACERO chief engineer Joey Mercer, right, shows the Portable Airspace Management System (PAMS) to Cal Fire representatives Scott Eckman, center, and Pete York, left, in preparation for the launch of the Overwatch Aero FVR90 Vertical Take Off and Landing (VTOL) test “fire” information sharing, airspace management, communication relay, and aircraft deconfliction capabilities during the Advanced Capabilities for Emergency Response Operations (ACERO) test in Salinas, California.NASA/Brandon Torres-Navarrete These latest flights build on successful PAMS testing in Watsonville, California, in November 2024. ACERO will use flight test data and feedback from wildland fire agencies to continue building out PAMS capabilities and will showcase more robust information-sharing capabilities in the coming years.  
      NASA’s goal for ACERO is to validate this technology, so it can be developed for wildland fire crews to use in the field, saving lives and property. The project is managed by NASA’s Airspace Operations and Safety Program and supports the agency’s  Advanced Air Mobility mission. 
      ACERO’s PAMS unit shown during a flight test on March 19, 2025NASA/Brandon Torres-Navarrette Share
      Details
      Last Updated Mar 25, 2025 Related Terms
      General Aeronautics Air Traffic Solutions Drones & You Natural Disasters Wildfires Wildland Fire Management Explore More
      3 min read New Aircraft Wing Undergoes Crucial NASA Icing Testing
      Article 3 hours ago 3 min read Engineering Reality: Lee Bingham Leads Lunar Surface Simulation Support for Artemis Campaign
      Article 21 hours ago 3 min read Career Transition Assistance Plan (CTAP) Services
      Article 1 day ago Keep Exploring Discover More Topics From NASA
      Missions
      Humans in Space
      Climate Change
      Solar System
      View the full article
    • By NASA
      5 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      In-person participants (L-R) – Back row: Jason Lytle, Stuart Lee, Eric Bershad, Ashot Sargsyan, Aaron Everson, Philip Wells, Sergi Vaquer Araujo, Steven Grover, John A. Heit, Mehdi Shishehbor, Laura Bostick; Middle row: Sarah Childress Taoufik, Stephan Moll, Brandon Macias, Kristin Coffey, Ann-Kathrin Vlacil, Dave Francisco; Front row: James Pavela, Doug Ebert, Kathleen McMonigal, Esther Kim, Emma Hwang; Not pictured: Tyson Brunstetter, J. D. Polk
      Online participants: Stephen Alamo, Mark Crowther, Steven Nissen, Mark Rosenberg, Jeffrey Weitz, R. Eugene Zierler, Serena Aunon, Tina Bayuse, Laura Beachy, Becky Brocato, Daniel Buckland, Jackie Charvat, Diana Cruz Topete, Quinn Dufurrena, Robert Haddon, Joanne Kaouk, Kim Lowe, Steve Laurie, Karina Marshall-Goebel, Sara Mason, Shannan Moynihan, James Pattarini, Devan Petersen, Ruth Reitzel, Donna Roberts, Lucia Roccaro, Mike Stenger, Terry Taddeo, Gavin Travers, Mary Van Baalen, Liz WarrenNASA In October 2024, NASA’s Office of the Chief Health and Medical Officer (OCHMO) initiated a working group to review the status and progress of research and clinical activities intended to mitigate the risk of venous thromboembolism (VTE) during spaceflight. The working group took place over two days at NASA’s Johnson Space Center; a second meeting on the topic was held in December 2024 at the European Space Agency (ESA) facility in Cologne, Germany.
      Read More about the Risk of VTE The working group was assembled from internal NASA subject matter experts (SMEs), the NASA OCHMO Standards Team, NASA and ESA stakeholders, and external SMEs, including physicians and medical professionals from leading universities and medical centers in the United States and Canada.

      Background
      Spaceflight Venous Thrombosis (SVT)
      Spaceflight Venous Thrombosis (SVT) refers to a phenomenon experienced during spaceflight in which a thrombus (blood clot) forms in the internal jugular vein (and/or associated vasculature) that may be symptomatic (thrombus accompanied by, but not limited to, visible internal jugular vein swelling, facial edema beyond “nominal” spaceflight adaptation, eyelid edema, and/or headache) or asymptomatic. Obstructive thrombi have been identified in a very small number of crewmembers, as shown in the figure below.

      Note that the figure below is for illustrative purposes only; locations are approximate, and size is not to scale.

      Approximate location of identified thrombi in crewmembers.Source: Modified from Cerebral Sinus Venous Thrombosis – University of Colorado Denver With treatment, crewmembers were able to complete their mission, and anticoagulants were discontinued several days prior to landing to minimize the risk of bleeding in the event of a traumatic injury. Some thromboses completely resolved post landing, and some required additional treatment.
      Pathophysiology of Venous Thromboembolism (VTE)
      The proposed pathogenesis of VTE is referred to as Virchow’s triad and suggests that VTE occurs as the result of:
      Alterations in blood flow (i.e., stasis), Vascular endothelial injury/changes, and/or, Alterations in the constituents of the blood leading to hypercoagulability (i.e., hereditary predisposition or acquired hypercoagulability). Note: pathophysiology are the changes that occur during a disease process; hypercoagulability is the increased tendency to develop blood to clots.
      The Virchow’s triad of risk factors for venous thrombosis.Bouchnita, 2017 Blood stasis, or venous stasis, refers to a condition in which the blood flow in the veins slows down which leads to pooling in the veins. This slowing of the blood may be due to vein valves becoming damaged or weak, immobility, and/or the absence of muscular contractions. Associated symptoms include swelling, skin changes, varicose veins, and slow-healing sores or ulcers. In terrestrial medicine, venous thrombosis is typically caused by damaged or weakened vein valves, which can be due to many factors, including aging, blood clots, varicose veins, obesity, pregnancy, sedentary lifestyle, estrogen use, and hereditary predisposition.

      Spaceflight Considerations
      Altered Venous Blood Flow and Spaceflight Associated Neuro-ocular Syndrome

      In addition to the terrestrial risk factors of VTE, there are physiological changes associated with spaceflight that are hypothesized to potentially play a role in the development of VTE in weightlessness. Specifically, researchers have explored the effects of the microgravity environment and subsequent observed headward fluid shifts that occur, and the potential impact on blood flow. Crewmembers onboard the International Space Station (ISS) experience weightlessness due to the microgravity environment and thus experience a sustained redistribution of bodily fluids from the legs toward the head. The prolonged headward fluid shifts during weightlessness results in facial puffiness, decreased leg volume, increased cardiac stroke volume, and decreased plasma volume.
      Crewmembers have also experienced altered blood flow during spaceflight, including retrograde venous blood flow (RVBF) (the backflow of venous blood towards the brain) or stasis (a stoppage or slowdown in the flow of blood). While the causes of the observed stasis and retrograde blood flow in spaceflight participants is not well understood, the potential clinical significance of the role it may have in the development of thrombus formation warrants further investigation.
      Doppler imaging of a retrograde flow in the left internal jugular vein.Yan & Seow, 2009 Other physiological concerns affected by fluid shifts are being studied to consider if any relation to VTE exists. Chronic weightlessness can cause bodily fluids such as blood and cerebrospinal fluid to move toward the head, which can lead to optic nerve swelling, folds in the retina, flattening of the back of the eye, and swelling in the brain. This collection of eye and brain changes is called “spaceflight associated neuro-ocular syndrome,” or SANS. Some astronauts only experience mild changes in space, while others have clinically significant outcomes. The long-term health outcome from these changes is unknown but actively being investigated. The risk of developing SANS is higher during longer-duration missions and remains a top research priority for scientists ahead of a Mars mission.
      Conclusions and Further Work
      Based on expert opinion and the assessment of the risk factors for thrombosis, an algorithm was developed to provide guidance for in-mission assessment and treatment of thrombus formation in weightlessness. The algorithm is based on early in-flight ultrasound testing to determine the flow characteristic of the left internal jugular vein and associated vasculature.
      NASA Working Group Recommendations
      The working group recommended several areas for further investigation to assess feasibility and potential to mitigate the risk of thrombosis in spaceflight:
      Improved detection capabilities to identify when a thrombus has formed in-flight, Pathophysiology/factors leading to thrombi formation during spaceflight, Countermeasures and treatment
      For more information on the working group meeting and a complete list of references, please see the Risk of Venous Thromboembolism (VTE) During Spaceflight Summary Report.
      Risk of Venous Thromboembolism (VTE) During Spaceflight Summary Report Share
      Details
      Last Updated Mar 14, 2025 EditorKim Lowe Related Terms
      Office of the Chief Health and Medical Officer (OCHMO) Astronauts General Human Health and Performance Humans in Space The Human Body in Space Keep Exploring Discover Related Topics
      OCHMO Independent Assessments
      Independent assessment plays a crucial role in NASA’s long-term success by addressing essential questions requiring rapid response to support further…
      Aerospace Medical Certification Standard
      This NASA Technical Standard provides medical requirements and clinical procedures designed to ensure crew health and safety and occupational longevity…
      Human Spaceflight Standards
      The Human Spaceflight & Aviation Standards Team continually works with programs to provide the best standards and implementation documentation to…
      Human Spaceflight and Aviation Standards
      The Human Spaceflight and Aviation Standards Team continuously works with subject matter experts and with each space flight program to…
      View the full article
    • By NASA
      1 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      The space shuttle Endeavour is seen on launch pad 39a as a storm passes by prior to the rollback of the Rotating Service Structure (RSS), Thursday, April 28, 2011, at Kennedy Space Center in Cape Canaveral, Fla. During the 14-day mission, Endeavour and the STS-134 crew will deliver the Alpha Magnetic Spectrometer (AMS) and spare parts including two S-band communications antennas, a high-pressure gas tank and additional spare parts for Dextre. Launch is targeted for Friday, April 29 at 3:47 p.m. EDT.NASA It is important to protect humans from unintended electrical current flow during spaceflight. The thresholds for contact electrical shock are well established, and standards and requirements exist that minimize the probability of contact electrical shock. Current thresholds were chosen (vs. voltage thresholds) because body impedance varies depending on conditions such as wet/dry, AC/DC, voltage level, large/small contact area, but current thresholds and physiological effects do not change. By addressing electrical thresholds, engineering teams are able to provide the appropriate hazard controls, usually through additional isolation (beyond the body’s impedance), current limiters, and/or modifying the voltage levels. Risk assessment determined that the probability of an event was extremely low, and the most serious consequence is expected to be involuntary muscle contraction.
      Lightning strikes the Launch Pad 39B protection system as preparations for launch of NASA’s Space Launch System (SLS) rocket with the Orion spacecraft aboard continue, Saturday, Aug. 27, 2022, at NASA’s Kennedy Space Center in Florida. NASA’s Artemis I flight test is the first integrated test of the agency’s deep space exploration systems: the Orion spacecraft, SLS rocket, and supporting ground systems. Launch of the uncrewed flight test is targeted for no earlier than Aug. 29 at 8:33 a.m. ET. Photo Credit: (NASA/Bill Ingalls) Directed Acyclic Graph Files
      + DAG File Information (HSRB Home Page)
      + Electrical Shock Risk DAG and Narrative (PDF)
      + Electrical Shock Risk DAG Code (TXT)
      Human System Risks Share
      Details
      Last Updated Mar 11, 2025 EditorRobert E. LewisLocationJohnson Space Center Related Terms
      Human Health and Performance Human System Risks Explore More
      1 min read Risk of Toxic Substance Exposure
      Article 15 mins ago 1 min read Risk of Urinary Retention
      Article 15 mins ago 1 min read Risk to Vehicle Crew Egress Capability and Task Performance as Applied to Earth and Extraterrestrial Landings
      Article 14 mins ago Keep Exploring Discover More Topics From NASA
      Humans In Space
      Missions
      International Space Station
      Solar System
      View the full article
    • By NASA
      1 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      Astronaut Serena M. Auñón-Chancellor Examines Her Eyes in SpaceNASA Exposure to altered gravity can cause ocular and brain structural changes to develop during spaceflight; these changes could lead to vision alterations, cognitive effects, or other deleterious health effects. SANS is a syndrome unique to humans that fly in space, and there is no terrestrial disease equivalent. Brain structural changes appear small but seem to indicate that over half of crewmembers experience one or more symptoms of SANS. Determining intracranial pressure during spaceflight could improve our understanding of SANS mechanisms and improve our ability to target countermeasures for determining risk for future missions.
      NASA astronaut Karen Nyberg, Expedition 36 flight engineer, conducts an ocular health exam on herself in the Destiny laboratory of the Earth-orbiting International Space Station. (NASA)NASA Directed Acyclic Graph Files
      + DAG File Information (HSRB Home Page)
      + SANS Risk DAG and Narrative (PDF)
      + SANS Risk DAG Code (TXT)
      Human Research Roadmap
      + Risk of Spaceflight Associated Neuro-ocular Syndrome
      + 2022 April Evidence Report (PDF)
      Human System Risks Share
      Details
      Last Updated Mar 11, 2025 EditorRobert E. LewisLocationJohnson Space Center Related Terms
      Human Health and Performance Human System Risks Explore More
      1 min read Risk of Toxic Substance Exposure
      Article 15 mins ago 1 min read Risk of Urinary Retention
      Article 15 mins ago 1 min read Risk to Crew Health Due to Electrical Shock (Electrical Shock Risk)
      Article 15 mins ago Keep Exploring Discover More Topics From NASA
      Humans In Space
      Missions
      International Space Station
      Solar System
      View the full article
  • Check out these Videos

×
×
  • Create New...