The goals of the working group were to:

1. Endorse or recommend changes to H2S SMAC levels that had been proposed by the JSC Toxicology Laboratory
2. Review a draft H2S SMAC manuscript prepared by the JSC Toxicology Laboratory
3. Provide any additional insight and consideration regarding H2S toxicity that should be considered for spaceflight programs

Background

The NASA Spaceflight Human-System Standard (NASA-STD-3001) establishes that vehicle systems shall limit atmospheric contamination below established limits [V2 6050] Atmosphere Contamination Limit. The JSC Toxicology Laboratory maintains the JSC 20584 Spacecraft Maximum Allowable Concentrations for Airborne Contaminants document, which contains a table of SMAC values for a variety of chemicals including carbon monoxide, ammonia, heavy metals, and a wide range of volatile organic compounds. SMACs are documented for 1-hr, 24-hr, 7-day, 30-day, 180-day, and 1000-day time spans for each chemical, and express the maximum concentration to which spaceflight crew can be exposed for that duration.

The organ system that is affected as well as the effect (symptoms) are also documented for each SMAC. For more information on SMACs, see this article Exposure Guidelines (SMACs and SWEGs) – NASA and the OCHMO Spaceflight Toxicology technical brief technical brief.

A SMAC value for hydrogen sulfide has not previously been established since it has not been of concern in spacecraft. However, with Artemis missions returning to the moon there is a possibility that H₂S could be released within spacecraft during lunar sample return, given that this compound may be a component of lunar polar ice. H₂S has an intense smell of rotten eggs and therefore has a distracting psychological element. Physiologically it has been shown to be an irritant at low concentrations and in high concentrations can potentially lead to neurological effects and unconsciousness.

Hydrogen sulfide SMAC values will define safe limits for spaceflight crews on future missions and could drive new requirements for monitoring and mitigation of this chemical during spaceflight.

Conclusions

Key points of the review were:

1. The proposed 1-hour, 24-hour, 7-day, 30-day, and 180-day SMAC values were deemed appropriate and were endorsed by each of the panel members.
2. The proposed 1000-day SMAC value is so low that the panel’s opinion is that this SMAC may not be attainable due to human-generated sources, and that these concentrations do not represent a true toxicological risk. The recommendation is to eliminate the 1000-day SMAC, or to call it a guideline.
3. The general SMAC calculation approach and inclusion of safety factors is logical, although some additional rationale would be justified.
4. Interactive and additive effects with other substances are considered negligible, particularly at these low concentrations.
5. Microgravity-induced physiological changes are unlikely to exacerbate hydrogen sulfide exposure at these low concentrations.
6. Recommendations were made with the understanding that these SMACs apply to pre-screened, healthy astronauts. For private spaceflight participants who may not be as well screened, the panel recommended individual physician attention and a review of all SMACs (including hydrogen sulfide), to identify sensitivities in certain populations (existing disease states, etc.).
7. Passive dosimetry technology is available and should be considered for long-term monitoring at these low concentrations.

Following consideration of the panel’s recommendation, the NASA/TM-20240000101 Exposure Limits for Hydrogen Sulfide in Spaceflight was revised and released by the JSC toxicology group in January of 2024 and is available below.

About the Author

Kim Lowe

Human Systems Standards Integrator

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President Biden has named 19 researchers who contribute to NASA’s mission as recipients of the Presidential Early Career Award for Scientists and Engineers (PECASE). These recipients are among nearly 400 federally funded researchers receiving the honor.  

Established in 1996 by the National Science and Technology Council, the PECASE Award is the highest honor given by the U.S. government to scientists and engineers who are beginning their research careers. The award recognizes recipients’ potential to advance the frontiers of scientific knowledge and their commitment to community service, as demonstrated through professional leadership, education or community outreach. 

“I am so impressed with these winners and what they have accomplished,” said Kate Calvin, chief scientist, NASA Headquarters in Washington. “They have made valuable contributions to NASA science and engineering, and I can’t wait to see what they do in the future.” 

The following NASA recipients were nominated by the agency: 

• Natasha Batalha, NASA Ames Research Center, Silicon Valley, California – for transformational scientific research in the development of open-source systems for the modeling of exoplanet atmospheres and observations 

• Elizabeth Blaber, Rensselaer Polytechnic Institute, Troy, New York – for transformative spaceflight and ground-based space biology research 

• James Burns, University of Virginia, Charlottesville – for innovative research at the intersection of metallurgy, solid mechanics and chemistry  

• Egle Cekanaviciute, NASA Ames Research Center – for producing transformational research to enable long-duration human exploration on the Moon and Mars 

• Nacer Chahat, NASA Jet Propulsion Laboratory, Southern California – for leading the innovation of spacecraft antennas that enable NASA deep space and earth science missions 

• Ellyn Enderlin, Boise State University, Idaho – for innovative methods to study glaciers using a wide variety of satellite datasets 

• David Estrada, Boise State University, Idaho – for innovative research in the areas of printed electronics for in space manufacturing and sensors for harsh environments 

• Burcu Gurkan, Case Western Reserve University, Cleveland, Ohio – for transforming contemporary approaches to energy storage and carbon capture to be safer and more economical, for applications in space and on Earth 

• Elliott Hawkes, University of California, Santa Barbara – for highly creative innovations in bio-inspired robotics that advance science and support NASA’s mission 

• John Hwang, University of California, San Diego – for innovative approach to air taxi design and key contributions to the urban air mobility industry  

• James Tuttle Keane, NASA Jet Propulsion Laboratory – for innovative and groundbreaking planetary geophysics research, and renowned planetary science illustrations 

• Kaitlin Kratter, University of Arizona, Tucson – for leadership in research about the formation and evolution of stellar and planetary systems beyond our own  

• Lyndsey McMillon-Brown, NASA Glenn Research Center, Cleveland, Ohio – for leadership in photovoltaic research, development, and demonstrations 

• Debbie Senesky, Stanford University, California – for research that has made it possible to operate sensing and electronic devices in high-temperature and radiation-rich environments 

• Hélène Seroussi, Dartmouth College, Hanover, New Hampshire  – for leading the cryosphere science community in new research directions about the role of ocean circulation in the destabilization of major parts of Antarctica’s ice sheets 

• Timothy Smith, NASA Glenn Research Center – for achievements in materials science research, specifically in high temperature alloy innovation 

• Mitchell Spearrin, University of California, Los Angeles – for pioneering scientific and technological advancements in multiple areas critical to NASA’s current and future space missions including rocket propulsion, planetary entry, and sensor systems 

• Michelle Thompson, Purdue University, West Lafayette, Indiana  – for research in planetary science and dedication to training the next generation of STEM leaders 

• Mary Beth Wilhelm, NASA Ames Research Center – for achievements in science, technology, and community outreach through her work in the fields of space science and astrobiology 

The PECASE awards were created to highlight the importance of science and technology for America’s future. These early career awards foster innovative developments in science and technology, increase awareness of careers in science and engineering, provide recognition to the scientific missions of participating agencies, and enhance connections between research and challenges facing the nation. For a complete list of award winners, visit: 

https://www.whitehouse.gov/ostp/news-updates/2025/01/14/president-biden-honors-nearly-400-federally-funded-early-career-scientists

NASA’s Sustainable Business Model Challenge is looking for entrepreneurs, startups, and researchers to leverage the agency’s publicly available Earth system science data to develop commercial solutions for climate challenges.

This opportunity, with a submission deadline of June 13, bridges the gap between vast climate data and actionable solutions by inviting solvers to transform data into sustainable business models that support climate resilience and decision-making.

“Creative, outcome-driven entrepreneurs are the lifeblood of our country’s economy, and we’re excited to see the sustainable climate solutions they’re able to come up with when working closely with NASA’s vast resources and data,” said Jason L. Kessler, program executive for the NASA Small Business Innovation Research / Small Business Technology Transfer (SBIR/STTR) program, which is sponsoring the challenge.

Through the Sustainable Business Model Challenge, NASA aims to foster a new set of sustainable enterprises capable of turning climate insights into tangible market-ready services, ultimately contributing to a more resilient future for vulnerable communities, businesses, and ecosystems. NASA is committed to broadening participation in its solicitations and fostering technology advancements.

By engaging new entrepreneurs, the challenge serves as a pathway to NASA’s SBIR/STTR program, helping scale solutions to advance the global response to climate change and encourage a more sustainable future. From its vantage point in space, NASA holds a wealth of data that can inform new approaches to climate adaptation and mitigation.

Participants will submit a 10-page business concept paper that includes details on how they will incorporate NASA climate or Earth system data to deliver a product or service. Up to ten winning teams will receive $10,000 each, along with admission to a 10-week capability development training designed to strengthen any future proposals for potential NASA funding.

NASA’s SBIR/STTR program, managed by the agency’s Space Technology Mission Directorate, is part of America’s Seed Fund, the nation’s largest source of early-stage funding for innovative technologies. Through this program, entrepreneurs, startups, and small businesses with less than 500 employees can receive funding and non-monetary support to build, mature, and commercialize their technologies, advancing NASA missions and advancing the nations aerospace economy.

Ensemble is hosting the challenge on behalf of NASA. The NASA Tournament Lab, part of the Prizes, Challenges, and Crowdsourcing program in the Space Technology Mission Directorate, manages the challenge. The program supports global public competitions and crowdsourcing as tools to advance NASA research and development and other mission needs.

The deadline to participate in NASA’s Sustainable Business Model Challenge is June 13, 2025.

For more information about the challenge, visit: https://nasabusinesschallenge.org/ 

President Biden has named 19 researchers who contribute to NASA’s mission as recipients of the Presidential Early Career Award for Scientists and Engineers (PECASE). These recipients are among nearly 400 federally funded researchers receiving the honor.  

Established in 1996 by the National Science and Technology Council, the PECASE Award is the highest honor given by the U.S. government to scientists and engineers who are beginning their research careers. The award recognizes recipients’ potential to advance the frontiers of scientific knowledge and their commitment to community service, as demonstrated through professional leadership, education or community outreach. 

“I am so impressed with these winners and what they have accomplished,” said Kate Calvin, chief scientist, NASA Headquarters in Washington. “They have made valuable contributions to NASA science and engineering, and I can’t wait to see what they do in the future.” 

The following NASA recipients were nominated by the agency: 

• Natasha Batalha, NASA Ames Research Center, Silicon Valley, California – for transformational scientific research in the development of open-source systems for the modeling of exoplanet atmospheres and observations 

• Elizabeth Blaber, Rensselaer Polytechnic Institute, Troy, New York – for transformative spaceflight and ground-based space biology research 

• James Burns, University of Virginia, Charlottesville – for innovative research at the intersection of metallurgy, solid mechanics and chemistry  

• Egle Cekanaviciute, NASA Ames Research Center – for producing transformational research to enable long-duration human exploration on the Moon and Mars 

• Nacer Chahat, NASA Jet Propulsion Laboratory, Southern California – for leading the innovation of spacecraft antennas that enable NASA deep space and earth science missions 

• Ellyn Enderlin, Boise State University, Idaho – for innovative methods to study glaciers using a wide variety of satellite datasets 

• David Estrada, Boise State University, Idaho – for innovative research in the areas of printed electronics for in space manufacturing and sensors for harsh environments 

• Burcu Gurkan, Case Western Reserve University, Cleveland, Ohio – for transforming contemporary approaches to energy storage and carbon capture to be safer and more economical, for applications in space and on Earth 

• Elliott Hawkes, University of California, Santa Barbara – for highly creative innovations in bio-inspired robotics that advance science and support NASA’s mission 

• John Hwang, University of California, San Diego – for innovative approach to air taxi design and key contributions to the urban air mobility industry  

• James Tuttle Keane, NASA Jet Propulsion Laboratory – for innovative and groundbreaking planetary geophysics research, and renowned planetary science illustrations 

• Kaitlin Kratter, University of Arizona, Tucson – for leadership in research about the formation and evolution of stellar and planetary systems beyond our own  

• Lyndsey McMillon-Brown, NASA Glenn Research Center, Cleveland, Ohio – for leadership in photovoltaic research, development, and demonstrations 

• Debbie Senesky, Stanford University, California – for research that has made it possible to operate sensing and electronic devices in high-temperature and radiation-rich environments 

• Hélène Seroussi, Dartmouth College, Hanover, New Hampshire  – for leading the cryosphere science community in new research directions about the role of ocean circulation in the destabilization of major parts of Antarctica’s ice sheets 

• Timothy Smith, NASA Glenn Research Center – for achievements in materials science research, specifically in high temperature alloy innovation 

• Mitchell Spearrin, University of California, Los Angeles – for pioneering scientific and technological advancements in multiple areas critical to NASA’s current and future space missions including rocket propulsion, planetary entry, and sensor systems 

• Michelle Thompson, Purdue University, West Lafayette, Indiana  – for research in planetary science and dedication to training the next generation of STEM leaders 

• Mary Beth Wilhelm, NASA Ames Research Center – for achievements in science, technology, and community outreach through her work in the fields of space science and astrobiology 

The PECASE awards were created to highlight the importance of science and technology for America’s future. These early career awards foster innovative developments in science and technology, increase awareness of careers in science and engineering, provide recognition to the scientific missions of participating agencies, and enhance connections between research and challenges facing the nation. For a complete list of award winners, visit: 

https://www.whitehouse.gov/ostp/news-updates/2025/01/14/president-biden-honors-nearly-400-federally-funded-early-career-scientists

Teams with NASA are gaining momentum as work progresses toward future lunar missions for the benefit of humanity as numerous flight hardware shipments from across the world arrived at the agency’s Kennedy Space Center in Florida for the first crewed Artemis flight test and follow-on lunar missions. The skyline at Kennedy will soon see added structures as teams build up the ground systems needed to support them.

Crews are well underway with parallel preparations for the Artemis II flight, as well as buildup of NASA’s mobile launcher 2 tower for use during the launch of the SLS (Space Launch System) Block 1B rocket, beginning with the Artemis IV mission. This version of NASA’s rocket will use a more powerful upper stage to launch with crew and more cargo on lunar missions. Technicians have begun upper stage umbilical connections testing that will help supply fuel and other commodities to the rocket while at the launch pad.

In summer 2024, technicians from NASA and contractor Bechtel National, Inc. completed a milestone called jack and set, where the center’s mega-mover, the crawler transporter, repositioned the initial steel base assembly for mobile launcher 2 from temporary construction shoring to its six permanent pedestals near the Kennedy’s Vehicle Assembly Building.   

“The NASA Bechtel mobile launcher 2 team is ahead of schedule and gaining momentum by the day,” stated Darrell Foster, ground systems integration manager, NASA’s Exploration Ground Systems Program at NASA Kennedy. “In parallel to all of the progress at our main build site, the remaining tower modules are assembled and outfitted at a second construction site on center.”

As construction of the mobile launcher 2’s base continues, the assembly operations shift into integration of the modules that will make up the tower. In mid-October 2024, crews completed installation of the chair, named for its resemblance to a giant seat. The chair serves as the interface between the base deck and the vertical modules which are the components that will make up the tower, and stands at 80-feet-tall.

In December 2024, teams completed the rig and set Module 4 operation where the first of a total of seven 40-foot-tall modules was stacked on top of the chair. Becthel crews rigged the module to a heavy lift crane, raised the module more than 150-feet, and secured the four corners to the tower chair. Once complete, the entire mobile launcher structure will reach a height of nearly 400 feet – approximately the length of four Olympic-sized swimming pools placed end-to-end.

On the opposite side of the center, test teams at the Launch Equipment Test Facility are testing the new umbilical interfaces, which will be located on mobile launcher 2, that will be needed to support the new SLS Block 1B Exploration Upper Stage. The umbilicals are connecting lines that provide fuel, oxidizer, pneumatic pressure, instrumentation, and electrical connections from the mobile launcher to the upper stage and other elements of SLS and NASA’s Orion spacecraft.

“All ambient temperature testing has been successfully completed and the team is now beginning cryogenic testing, where liquid nitrogen and liquid hydrogen will flow through the umbilicals to verify acceptable performance,” stated Kevin Jumper, lab manager, NASA Launch Equipment Test Facility at Kennedy. “The Exploration Upper Stage umbilical team has made significant progress on check-out and verification testing of the mobile launcher 2 umbilicals.”

The testing includes extension and retraction of the Exploration Upper Stage umbilical arms that will be installed on mobile launcher 2. The test team remotely triggers the umbilical arms to retract, ensuring the ground and flight umbilical plates separate as expected, simulating the operation that will be performed at lift off.

Science in Space January 2025

At the start of a new year, many people think about making positive changes in their lives, such as improving physical fitness or learning a particular skill. Astronauts on the International Space Station work all year to maintain a high level of performance while adapting to changes in their physical fitness, cognitive ability, sensory perception, and other functions during spaceflight.

Research on the space station looks at how these qualities change in space, the ways those changes affect daily performance, and countermeasures to keep astronauts at their peak.

A current CSA (Canadian Space Agency) investigation, Space Health, assesses the effects of spaceflight on cardiovascular deconditioning. The investigation uses Bio-Monitor, wearable sensors that collect data such as pulse rate, blood pressure, breathing rate, skin temperature, and physical activity levels. Results could support development of an autonomous system to monitor cardiovascular health on future space missions. Similar technology could be used to monitor heart health in people on Earth.

Maintaining muscle fitness

During spaceflight, astronauts lose muscle mass and stiffness, an indication of strength. Astronauts exercise daily to counteract these effects, but monitoring the effectiveness of exercise had been limited to before and after flight due to the lack of technologies appropriate for use in space. The ESA (European Space Agency) Myotones investigation demonstrated that a small, non-invasive device accurately measured muscle stiffness and showed that current countermeasures seem to be effective for most muscle groups. Accurate inflight assessment could help scientists target certain muscles to optimize the effectiveness of exercise programs on future missions. The measuring device also could benefit patients in places on Earth without other means for monitoring.

Keeping a sharp mind

Research suggests that the effects of spaceflight on cognitive performance likely are due to the influence of stressors such as radiation and sleep disruption. Longer missions that increase the exposure to these hazards may change how they affect individuals.

Manual Control used a battery of tests to examine how spaceflight affects cognitive, sensory, and motor function right after landing. The day they return from spaceflight, astronauts demonstrate significant impairments in fine motor control and ability to multitask in simulated flying and driving challenges. Researchers attribute this to subtle physiological changes during spaceflight. Performance recovered once individuals were exposed to a task, suggesting that having crew members conduct simulated tasks right before actual ones could be beneficial. This work helps scientists ensure that crew members can safely land and conduct early operations on the Moon and Mars.

Standard Measures collects a set of physical and mental measurements related to human spaceflight risks, including a cognition test battery, from astronauts before, during, and after missions. Using these data, researchers found that astronauts on 6-month missions demonstrated generally stable cognitive performance with mild changes in certain areas, including processing speed, working memory, attention, and willingness to take risks. The finding provides baseline data that could help identify cognitive changes on future missions and support development of appropriate countermeasures. This research includes the largest sample of professional astronauts published to date.

Evaluating perception

Another function that can be affected by spaceflight is sensory perception, such as the ability to interpret motion, orientation, and distance. We use our visual perception of the height and width of objects around us, for example, to complete tasks such as reaching for an object and deciding whether we can fit through an opening. VECTION, a CSA investigation, found that microgravity had no immediate effect on the ability to perceive the height of an object, indicating that astronauts can safely perform tasks that rely on this judgment soon after they arrive in space. Researchers concluded there is no need for countermeasures but did suggest that space travelers be made aware of late-emerging and potentially long-lasting changes in the ability to perceive object height.

Melissa Gaskill

International Space Station Research Communications Team

Johnson Space Center

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Air Traffic Control Association (ATCA) Award to the NASA ATM-X Digital Information Platform (DIP) Team
In November 2024, the Digital Information Platform (DIP) team received the prestigious Industry Award from the Air Traffic Control Association (ATCA) at the annual ATCA Connect Conference in Washington, DC. The award recognized the team’s efforts in supporting NASA’s Sustainable Flight National Partnership (SFNP), which aims for net-zero carbon emissions from aviation by 2050.  The DIP sub-project focuses on increasing access to digital aviation information to enable efficient and sustainable airspace operations.  DIP team has been conducting live operational demonstrations in North Texas Metroplex environment since 2022 with commercial airlines on the Collaborative Digital Departure Reroute (CDDR) tool that applies machine learning to make predictions on runway availability, departure times, and arrival times. DIP has signed Space Act Agreements with five major US airlines to carryout operational evaluation of CDDR in complex metroplex environments and is now deploying the CDDR capability to Houston. CDDR machine learning algorithm intelligently provides re-routing options to the operators by using real time weather and operational data reducing delays, fuel burn and carbon emissions. DIP is part of the Air Traffic Management – eXploration (ATM-X) project, which is focused on transforming the air traffic management system to accommodate new air vehicles.  More information on the ATCA award is at: https://www.atca.org/detail-pages/news/2024/11/15/atca-presents-annual-awards-at-atca-connect-recognizing-exceptional-efforts-made-to-the-worldwide-air-traffic-control-and-airspace-system.

NASA is bringing the high-stakes world of planetary defense to the Sundance Film Festival, highlighting its upcoming documentary, “Planetary Defenders,” during a panel ahead of its spring 2025 premiere on the agency’s streaming service.

“We’re thrilled that NASA is attending Sundance Film Festival for the first time – a festival renowned for its innovative spirit,” said Brittany Brown, director, NASA Office of Communications Digital and Technology Division, at the agency’s Headquarters in Washington. “Our participation represents a groundbreaking opportunity for NASA to engage with the film industry and share new avenues for collaborative storytelling. By connecting with the creative minds at the festival, we aim to inspire new narratives, explore new avenues for collaborative storytelling, and ignite a renewed sense of wonder in space exploration.”

The NASA+ film explores a compelling question: How would humanity respond if we discovered an asteroid headed for Earth? Far from science fiction, “Planetary Defenders” follows real-life astronomers and other experts as they navigate the challenges of asteroid detection and safeguarding our planet from potential hazards.

“NASA is home to some of the greatest stories ever told, and NASA’s new streaming platform NASA+ is dedicated to sharing these stories to inspire the next generation,” said Rebecca Sirmons, general manager and head of NASA+. “We are honored to host a panel at this year’s Sundance Film Festival discussing our upcoming NASA+ documentary “Planetary Defenders.”

The panel, entitled “You Bet Your Asteroid: NASA Has a Story to Tell,” will start at 1:30 p.m. MST on Sunday, Jan. 26, at the Filmmaker Lodge in the Elks Building, 550 Main St., 2nd Floor, Park City, Utah. The event will include a discussion about the film followed by a Q&A session. Attendees also will have the opportunity to meet NASA experts and some of the planetary defenders themselves.

Panelists include:

• Rebecca Sirmons, head of NASA+, NASA
• Scott Bednar, filmmaker and director, NASA 360/National Institute of Aerospace
• Jessie Wilde, filmmaker and director, NASA 360/National Institute of Aerospace
• Dr. Kelly Fast, acting planetary defense officer, NASA’s Planetary Defense Coordination Office
• David Rankin, senior survey operations specialist, Catalina Sky Survey
• Dr. Vishnu Reddy, professor of planetary sciences and director of the Space4 Center, University of Arizona

Media are encouraged to RSVP in advance and may request one-on-one interviews with NASA experts following the panel by contacting Karen Fox at karen.c.fox@nasa.gov.

Through NASA+, the agency is continuing its decades long tradition of sharing live events, original content, and the latest news while NASA works to improve life on Earth through innovation, exploration, and discovery for the benefit of all. The free, on-demand streaming service is available to download without a subscription on most major platforms via the NASA App on iOS and Android mobile and tablet devices, as well as streaming media players like Roku, Apple TV, and Fire TV.

To keep up with the latest news from NASA’s planetary defense program, visit:

https://www.nasa.gov/planetarydefense

-end-

Abbey Donaldson
Headquarters, Washington
202-358-1600
abbey.a.donaldson@nasa.gov

The Stone of Hope, a granite statue of civil rights movement leader Dr. Martin Luther King, Jr., is seen in this image from Jan. 5, 2025. The statue is part of the Martin Luther King, Jr. Memorial in Washington.

Dr. King inspired millions to answer the righteous call for racial equality and to build a world where every person is treated equally, with dignity and respect. NASA is committed to innovate for the benefit of humanity and to inspire the world through discovery.

Image credit: NASA/Bill Ingalls

Science in Space January 2025

At the start of a new year, many people think about making positive changes in their lives, such as improving physical fitness or learning a particular skill. Astronauts on the International Space Station work all year to maintain a high level of performance while adapting to changes in their physical fitness, cognitive ability, sensory perception, and other functions during spaceflight.

Research on the space station looks at how these qualities change in space, the ways those changes affect daily performance, and countermeasures to keep astronauts at their peak.

A current CSA (Canadian Space Agency) investigation, Space Health, assesses the effects of spaceflight on cardiovascular deconditioning. The investigation uses Bio-Monitor, wearable sensors that collect data such as pulse rate, blood pressure, breathing rate, skin temperature, and physical activity levels. Results could support development of an autonomous system to monitor cardiovascular health on future space missions. Similar technology could be used to monitor heart health in people on Earth.

Maintaining muscle fitness

During spaceflight, astronauts lose muscle mass and stiffness, an indication of strength. Astronauts exercise daily to counteract these effects, but monitoring the effectiveness of exercise had been limited to before and after flight due to the lack of technologies appropriate for use in space. The ESA (European Space Agency) Myotones investigation demonstrated that a small, non-invasive device accurately measured muscle stiffness and showed that current countermeasures seem to be effective for most muscle groups. Accurate inflight assessment could help scientists target certain muscles to optimize the effectiveness of exercise programs on future missions. The measuring device also could benefit patients in places on Earth without other means for monitoring.

Keeping a sharp mind

Research suggests that the effects of spaceflight on cognitive performance likely are due to the influence of stressors such as radiation and sleep disruption. Longer missions that increase the exposure to these hazards may change how they affect individuals.

Manual Control used a battery of tests to examine how spaceflight affects cognitive, sensory, and motor function right after landing. The day they return from spaceflight, astronauts demonstrate significant impairments in fine motor control and ability to multitask in simulated flying and driving challenges. Researchers attribute this to subtle physiological changes during spaceflight. Performance recovered once individuals were exposed to a task, suggesting that having crew members conduct simulated tasks right before actual ones could be beneficial. This work helps scientists ensure that crew members can safely land and conduct early operations on the Moon and Mars.

Standard Measures collects a set of physical and mental measurements related to human spaceflight risks, including a cognition test battery, from astronauts before, during, and after missions. Using these data, researchers found that astronauts on 6-month missions demonstrated generally stable cognitive performance with mild changes in certain areas, including processing speed, working memory, attention, and willingness to take risks. The finding provides baseline data that could help identify cognitive changes on future missions and support development of appropriate countermeasures. This research includes the largest sample of professional astronauts published to date.

Evaluating perception

Another function that can be affected by spaceflight is sensory perception, such as the ability to interpret motion, orientation, and distance. We use our visual perception of the height and width of objects around us, for example, to complete tasks such as reaching for an object and deciding whether we can fit through an opening. VECTION, a CSA investigation, found that microgravity had no immediate effect on the ability to perceive the height of an object, indicating that astronauts can safely perform tasks that rely on this judgment soon after they arrive in space. Researchers concluded there is no need for countermeasures but did suggest that space travelers be made aware of late-emerging and potentially long-lasting changes in the ability to perceive object height.

Melissa Gaskill

International Space Station Research Communications Team

Johnson Space Center

Keep Exploring

Discover More Topics From NASA

Space Station Research and Technology

Humans In Space

International Space Station News

Station Benefits for Humanity

Teams with NASA are gaining momentum as work progresses toward future lunar missions for the benefit of humanity as numerous flight hardware shipments from across the world arrived at the agency’s Kennedy Space Center in Florida for the first crewed Artemis flight test and follow-on lunar missions. The skyline at Kennedy will soon see added structures as teams build up the ground systems needed to support them.

Crews are well underway with parallel preparations for the Artemis II flight, as well as buildup of NASA’s mobile launcher 2 tower for use during the launch of the SLS (Space Launch System) Block 1B rocket, beginning with the Artemis IV mission. This version of NASA’s rocket will use a more powerful upper stage to launch with crew and more cargo on lunar missions. Technicians have begun upper stage umbilical connections testing that will help supply fuel and other commodities to the rocket while at the launch pad.

In summer 2024, technicians from NASA and contractor Bechtel National, Inc. completed a milestone called jack and set, where the center’s mega-mover, the crawler transporter, repositioned the initial steel base assembly for mobile launcher 2 from temporary construction shoring to its six permanent pedestals near the Kennedy’s Vehicle Assembly Building.   

“The NASA Bechtel mobile launcher 2 team is ahead of schedule and gaining momentum by the day,” stated Darrell Foster, ground systems integration manager, NASA’s Exploration Ground Systems Program at NASA Kennedy. “In parallel to all of the progress at our main build site, the remaining tower modules are assembled and outfitted at a second construction site on center.”

As construction of the mobile launcher 2’s base continues, the assembly operations shift into integration of the modules that will make up the tower. In mid-October 2024, crews completed installation of the chair, named for its resemblance to a giant seat. The chair serves as the interface between the base deck and the vertical modules which are the components that will make up the tower, and stands at 80-feet-tall.

In December 2024, teams completed the rig and set Module 4 operation where the first of a total of seven 40-foot-tall modules was stacked on top of the chair. Becthel crews rigged the module to a heavy lift crane, raised the module more than 150-feet, and secured the four corners to the tower chair. Once complete, the entire mobile launcher structure will reach a height of nearly 400 feet – approximately the length of four Olympic-sized swimming pools placed end-to-end.

On the opposite side of the center, test teams at the Launch Equipment Test Facility are testing the new umbilical interfaces, which will be located on mobile launcher 2, that will be needed to support the new SLS Block 1B Exploration Upper Stage. The umbilicals are connecting lines that provide fuel, oxidizer, pneumatic pressure, instrumentation, and electrical connections from the mobile launcher to the upper stage and other elements of SLS and NASA’s Orion spacecraft.

“All ambient temperature testing has been successfully completed and the team is now beginning cryogenic testing, where liquid nitrogen and liquid hydrogen will flow through the umbilicals to verify acceptable performance,” stated Kevin Jumper, lab manager, NASA Launch Equipment Test Facility at Kennedy. “The Exploration Upper Stage umbilical team has made significant progress on check-out and verification testing of the mobile launcher 2 umbilicals.”

The testing includes extension and retraction of the Exploration Upper Stage umbilical arms that will be installed on mobile launcher 2. The test team remotely triggers the umbilical arms to retract, ensuring the ground and flight umbilical plates separate as expected, simulating the operation that will be performed at lift off.

Climate change presents one of the most urgent crises of our time, with increasing threats to life, infrastructure, economies, and ecosystems worldwide. Climate change is no longer a distant concern; its effects are being felt now and are projected to intensify if emissions continue unabated. The consequences are severe and irreversible for people today, with rapidly shrinking glaciers and ice sheets, rising sea levels, and more intense heat waves already occurring. Scientists predict even more profound impacts, such as an increase in the frequency and intensity of wildfires, extended drought periods, and stronger tropical cyclones. By 2100, sea levels could rise by up to 6.5 feet1, displacing coastal communities and disrupting ecosystems. In the U.S., the effects vary by region—wildfires in the West have doubled in area burned, and rising sea levels threaten infrastructure in the Southeast. Innovative, data-driven solutions are essential to mitigate these growing risks. From the unique vantage point in space, NASA collects critical long-term observations of our changing planet. NASA produces vast amounts of Earth system science data from satellites, radars, and ships, as well as model outputs, offering a wealth of opportunities for innovative thinkers to leverage these sources. The Sustainable Business Model Challenge is designed to identify and foster sustainable business models built around NASA’s Earth system science data. This challenge invites entrepreneurs, researchers, startups, and innovators to use NASA’s publicly available climate and Earth system data sources to create sustainable business models to address climate challenges.

Award: $100,000 in total prizes

Open Date: January 16, 2025

Close Date: June 13, 2025

For more information, visit: https://nasabusinesschallenge.org/

On Jan. 17, 1990, NASA announced the selection of its 13^th group of astronaut candidates. The diverse group comprised 23 candidates – seven pilots and 16 mission specialists. The group included one African American, one Asian American, and five women including the first female pilot and the first Hispanic woman. Following one year of astronaut candidate training, all 23 became eligible for technical assignments within the astronaut office and for assignment to space shuttle crews. All members of the group completed at least one spaceflight, making significant contributions to the space shuttle program, the Shuttle Mir program, important science missions, and assembly and maintenance of the International Space Station. Several went on to serve in key NASA management positions. 

The newest class of NASA astronaut candidates included pilot candidates Kenneth Cockrell, Eileen Collins, William Gregory, James Halsell, Charles Precourt, Richard Searfoss, and Terrence Wilcutt and mission specialist candidates Daniel Bursch, Leroy Chiao, Rich Clifford, Bernard Harris, Susan Helms, Thomas Jones, William Mc Arthur, James Newman, Ellen Ochoa, Ronald Sega, Nancy Sherlock, Donald Thomas, Janice Voss, Carl Walz, Jeffrey Wisoff, and David Wolf. From the 1,945 qualified applicants, NASA invited 103 candidates for interviews and medical exams at NASA’s Johnson Space Center (JSC) in Houston between September and November 1989. 

The 23 astronaut candidates reported to work at JSC on July 16, 1990, to begin their one-year training period. During the yearlong training, the candidates attended classes in applied sciences, space shuttle systems, space medicine, Earth and planetary sciences, and materials sciences. They visited each of the NASA centers to learn about their functions and received instruction in flying the T-38 Talon training aircraft, high-altitude and ground egress systems, survival skills, parasail flight, and scuba. They experienced short-duration weightlessness aboard NASA’s KC-135 aircraft dubbed the Vomit Comet. After completing the astronaut candidate training, they qualified for various technical assignments within the astronaut office leading to assignments to space shuttle crews. 

Per tradition, most astronaut classes have a nickname, often humorously given to them by the previous class of astronauts. In the case of the class of 1990, they chose their own nickname, The Hairballs. The origin stems from the class adopting a black cat as their mascot, in recognition of their class number 13. The nickname came about as hairballs are often associated with cats. 

Daniel Bursch 

Born in Pennsylvania, Bursch grew up in New York state and graduated from the U.S. Naval Academy. He served as a pilot in the U.S. Navy prior to his selection as an astronaut. He received his first flight assignment as a mission specialist on STS-51, flying with fellow Hairballs Newman and Walz on the 10-day flight aboard Discovery in 1993. On his second mission, the 10-day STS-68 flight aboard Endeavour in 1994, Bursch, accompanied by fellow classmates Jones, Wilcutt, and Wisoff, served as a mission specialist on the Space Radar Laboratory-2 (SRL-2) Earth observation mission. For his third trip into space, Bursch flew as a mission specialist aboard Endeavour for the 10-day STS-77 mission in 1996. For his fourth and final spaceflight, Bursch, along with fellow Hairball Walz, spent 196 days in space as an Expedition 4 flight engineer aboard the space station in 2001 and 2002, conducting two spacewalks totaling 11 hours 46 minutes. He launched on STS-108 and returned on STS-111. Across his four missions, Bursch accumulated 227 days in space. 

Leroy Chiao 

California native Chiao earned a doctorate in chemical engineering from the University of California, Santa Barbara, before NASA selected him as an astronaut. For his first flight, he flew as a mission specialist on STS-65, the International Microgravity Lab-2 (IML-2) mission aboard Columbia in 1994. Fellow Hairballs Halsell, Walz, and Thomas accompanied Chiao on the nearly 15-day flight, the longest shuttle mission up to that time. During his second spaceflight, the nine-day STS-72 flight of Endeavour in 1996, Chiao participated in two spacewalks totaling 13 hours 3 minutes to demonstrate future techniques. In 2000, Chiao, accompanied by fellow classmates McArthur and Wisoff, flew the 13-day STS-92 3A space station assembly mission aboard Discovery. He participated in two spacewalks with classmate McArthur totaling 13 hours 16 minutes. For his fourth and final mission, Chiao served as commander of Expedition 10 in 2004 and 2005, spending 193 days in space. During the mission, he conducted two spacewalks totaling 9 hours 58 minutes. During his four flights, Chiao logged 229 days in space and spent more than 36 hours outside on his six spacewalks. 

Rich Clifford 

Clifford, born in California, grew up in Ogden, Utah. He holds the distinction as one of the first three astronauts of his class assigned to a spaceflight, the seven-day STS-53 mission aboard Discovery in 1992 to deploy a large satellite for the Department of Defense. His second flight, the SRL-1 mission aboard Endeavour took place in 1994. Fellow Hairball Jones accompanied him on the STS-59 11-day Earth observation mission. For his third and final spaceflight, Clifford flew as a mission specialist on the STS-76 third Shuttle Mir docking mission. During the nine-day mission in 1996, accompanied by fellow classmate Sega, Clifford participated in a six-hour one-minute spacewalk. During his three spaceflights, he accumulated nearly 28 days in space. 

Kenneth Cockrell 

Cockrell, a native Texan, served as naval aviator prior to his selection as an astronaut. On his first mission, STS-56, he served as a mission specialist for the nine-day ATLAS-2 Earth observation mission in 1993. Fellow classmate Ochoa accompanied him on the flight aboard Discovery. Cockrell served as pilot on his second mission, the 11-day STS-69 Endeavour flight in 1995 to deploy and retrieve the Wake Shield Facility. Classmate Voss accompanied him on this mission. Cockrell commanded his third spaceflight, STS-80 in 1996 aboard Columbia, accompanied by fellow Hairball Jones. At 17 days 15 hours 53 minutes days, it holds the distinction as the longest shuttle flight. He once again served as commander on his fourth mission, the STS-98 5A space station assembly flight in 2001. Accompanied by classmate Jones, the crew delivered the U.S. Laboratory Module Destiny during the 13-day mission. On his fifth and final spaceflight, Cockrell commanded the STS-111 space station UF-2 utilization mission in 2002. During the 14-day flight, the crew brought the Expedition 5 crew to the station and returned the Expedition 4 crew, including Hairballs Bursch and Walz. During his five missions, Cockrell accumulated 64.5 days in space. He served as Chief of the Astronaut Office from October 1997 to October 1998. 

Eileen Collins 

Hailing from New York state, Collins has the distinction as the first female selected by NASA as a shuttle pilot. She received her first flight assignment as pilot of STS-63, the eight-day Shuttle-Mir rendezvous mission in 1995. Fellow classmates Harris and Voss accompanied her aboard Discovery. Collins once again served as pilot on STS-84, the sixth Shuttle-Mir docking mission commanded by fellow Hairball Precourt. The nine-day flight aboard Atlantis took place in 1997. On her third flight, Collins served as the first female commander of a space mission, the five-day STS-93 flight of Columbia in 1999 to deploy the Chandra X-ray Observatory. She commanded her fourth and final mission, the STS-114 return to flight mission following the Columbia accident. The 14-day flight aboard Discovery took place in 2005. During her four missions, Collins logged 36 days in space. 

William Gregory 

New York native Gregory served as a U.S. Air Force pilot when NASA selected him as an astronaut. He flew his single mission as pilot of STS-67, the 17-day Astro-2 mission aboard Endeavour in 1995. The mission set a record for the longest shuttle flight up to that time. 

James Halsell 

Halsell, a native of Louisiana, served as a U.S. Air Force pilot when NASA selected him as an astronaut. On his first spaceflight, he served as pilot on STS-65, the IML-2 mission aboard Columbia in 1994. Fellow Hairballs Chiao, Walz, and Thomas accompanied Halsell on the nearly 15-day flight, the longest shuttle mission up to that time. Halsell once again served as pilot on his second flight, STS-74, the second Shuttle-Mir docking mission that delivered the Docking Module to Mir. Classmate McArthur joined Halsell on the eight-day Atlantis flight in 1995. He commanded his third spaceflight, STS-83 aboard Columbia, the Microgravity Sciences Lab in 1997. Because managers cut the flight short after four days due to a fuel cell failure, NASA decided to refly the mission, with the same crew, later in the year as STS-94, and it stayed in space for nearly 16 days. Classmates Voss and Thomas accompanied Halsell on both missions. Halsell also commanded his fifth and final spaceflight, the STS-101 2A.2a space station logistics mission in 2000. Classmate Helms accompanied Halsell on the 10-day mission aboard Atlantis. During his five missions, Halsell accumulated more than 52 days of spaceflight time.  

Bernard Harris 

Texas native Harris served as a NASA flight surgeon when the agency selected him as an astronaut. He holds the distinction as one of the first three astronauts of his class assigned to a spaceflight. He served as a mission specialist on the STS-55 joint U.S.-German Spacelab D2 mission in 1993. Fellow Hairball Precourt accompanied him on the 10-day flight aboard Columbia. Harris flew as payload commander on his second and final spaceflight, the STS-63 Mir rendezvous mission in 1995, accompanied by classmates Collins and Voss. During the flight, Harris conducted a 4-hour 49-minute spacewalk, earning the distinction as the first African American to do so. Across his two missions, Harris logged 18 days in space. 

Susan Helms 

Helms, a native of Portland, Oregon, graduated from the U.S. Air Force Academy in the first class that included women. Shortly after her selection as an astronaut, NASA assigned her to her first spaceflight, and she holds the distinction as one of the first three astronauts of her class assigned to a mission. She flew as a mission specialist on STS-54, a six-day flight aboard Endeavour in 1993 that deployed the sixth Tracking and Data Relay Satellite. On her second mission, Helms flew aboard STS-64, an 11-day flight aboard Discovery in 1994. She served as the payload commander on STS-78, the Life and Microgravity Sciences Spacelab mission aboard Columbia in 1996. The flight set a then-record of 16 days 22 hours for the longest space shuttle mission. On her fourth mission, she served as a mission specialist on STS-101, the 2A.2a space station logistics mission in 2000 commanded by classmate Halsell. The Atlantis mission lasted 10 days. For her fifth and final spaceflight, she served as a flight engineer during Expedition 2, the first woman to fly a long-duration mission on the International Space Station. She conducted one spacewalk lasting 8 hours 56 minutes, a record not broken until 2024. During her five spaceflights she logged 211 days in space. 

Thomas Jones 

Jones, a native of Baltimore, graduated from the U.S. Air Force Academy and served as a B-52 pilot when NASA selected him as an astronaut. For his first spaceflight, he served as a mission specialist on STS-59, the 11-day SRL-1 Earth observation mission on Endeavour in 1994, along with classmate Clifford. Later that same year, with just 163 days between the two missions – the second shortest turnaround time in history – Jones served as payload commander on STS-68, the 11-day SRL-2 mission also on Endeavour. Fellow Hairballs Wilcutt, Wisoff, and Bursch accompanied him on the mission. In 1996, Jones flew as a mission specialist on STS-80, commanded by classmate Cockrell. During the nearly 18-day flight – the longest shuttle flight in history – Jones had planned to participate in two spacewalks, but a stuck bolt prevented the opening of Columbia’s airlock hatch, forcing the cancelation of the excursions. Jones flew his fourth and final mission in 2001, the STS-98 5A space station assembly flight, commanded by classmate Cockrell. During the 13-day mission of Atlantis, the crew installed the U.S. Laboratory Module Destiny and Jones participated in three spacewalks totaling nearly 20 hours. During his four spaceflights, Jones logged 53 days in space. 

William McArthur 

Hailing from North Carolina, West Point graduate McArthur worked as a space shuttle vehicle integration test engineer at JSC when NASA selected him as an astronaut. He received his first spaceflight assignment as a mission specialist on the STS-58 Spacelab Life Sciences-2 (SLS-2) mission in 1993. Classmates Searfoss and Wolf accompanied him on the 14-day Columbia mission, at the time the longest space shuttle flight. In 1995, he flew as a mission specialist on STS-74, the second Shuttle Mir docking mission that brought the Docking Module to Mir. Classmate Halsell served as pilot on the eight-day flight of Atlantis. McArthur next flew on STS-92, the 3A space station assembly mission in 2000, accompanied by classmates Chiao and Wisoff. McArthur completed two spacewalks with Chiao totaling 13 hours 16 minutes during the 13-day Atlantis mission. For his fourth and final spaceflight, McArthur served as commander of the 190-day Expedition 12 in 2005-2006, conducting two spacewalks totaling 11 hours 5 minutes. During his four missions, McArthur logged 225 days in space and spent more than 24 hours on four spacewalks. He served as the director of the JSC Safety and Mission Assurance Directorate from 2011 to 2017. 

James Newman 

Born in Micronesia, Newman grew up in San Diego and earned a doctorate in physics from Rice University. He worked at JSC as a crew and flight controller trainer when NASA selected him as an astronaut. For his first spaceflight assignment, Newman flew as a mission specialist on STS-51 in 1993 with fellow Hairballs Bursch and Walz. During the 10-day mission aboard Discovery, Newman conducted a 7-hour 5-minute spacewalk with Walz to demonstrate future spacewalking techniques. His second flight took place in 1995, the 11-day STS-69 mission of Endeavour, with classmate Halsell serving as pilot. On his third mission, Newman flew as a mission specialist on STS-88, the first space station assembly flight in 1998. Classmate Sherlock, now using her married name Currie, accompanied him on the 12-day Atlantis mission. Newman participated in three spacewalks totaling 21 hours 22 minutes. For his fourth and final spaceflight in 2002, Newman flew on STS-109, the fourth servicing mission to the Hubble Space Telescope, accompanied once again by classmate Currie. During the 11-day Columbia mission, Newman conducted two spacewalks totaling 14 hours 46 minutes. During his career four spaceflights, Newman logged more than 43 days in space and spent nearly 50 hours on six spacewalks. 

Ellen Ochoa 

Born in Los Angeles, Ochoa received her doctorate in electrical engineering from Stanford University and worked at NASA’s Ames Research Center in California’s Silicon Valley when NASA selected her as an astronaut. Her first flight assignment came in 1993 when she flew as a mission specialist on STS-56, the nine-day ATLAS-2 Earth observation mission. Classmate Cockrell accompanied her on the Discovery mission. On her second spaceflight, she served as payload commander on the STS-66 ATLAS-3 mission, an 11-day flight of Atlantis in 1994. For her third flight, she flew on Discovery’s STS-96, the 10-day 2A.1 space station assembly and logistics mission in 1999. In 2002, on her fourth and final mission, STS-110, she served as a mission specialist on the 8A space station assembly flight that brought the S0 truss to the facility. The flight on Atlantis lasted nearly 11 days. Over her four missions, Ochoa accumulated nearly 41 days in space. Following her spaceflights, Ochoa served in management positions with increasing scope and responsibilities, as director of the Flight Crew Operations Directorate, JSC deputy director, and JSC director. 

Charles Precourt 

Massachusetts native Precourt graduated from the U.S. Air Force Academy and served as a U.S. Air Force pilot when NASA selected him as an astronaut. On his first spaceflight in 1993, he served as a mission specialist on STS-55, the joint U.S.-German Spacelab D2 mission. Fellow Hairball Harris accompanied him on the 10-day Columbia mission. On his next spaceflight, Precourt served as pilot on STS-71, the first Shuttle-Mir docking mission in 1995. The 10-day Atlantis mission included the first shuttle-based crew rotation. Precourt commanded his third spaceflight, STS-84 in 1987, the sixth Shuttle-Mir docking mission. Classmate Collins served as pilot on the nine-day Atlantis mission. He commanded his fourth and final space mission, STS-91, the ninth and final Shuttle-Mir docking flight, earning him the honor as the only American astronaut to visit Mir three times. The 10-day mission aboard Discovery took place in 1998. Across his four spaceflights, Precourt logged nearly 39 days in space. He served as chief of the Astronaut Office from October 1998 to November 2002. 

Richard Searfoss 

Born in Michigan, Searfoss graduated from the U.S. Air Force Academy and served as an instructor at the U.S. Air Force Test Pilot School when NASA selected him as an astronaut. On his first spaceflight, Searfoss served as pilot on STS-58, the SLS-2 mission in 1993. Classmates McArthur and Wolf joined him on the flight aboard Columbia, at 14 days then the longest space shuttle mission. In 1996, he once again served as pilot on STS-76, the third Shuttle-Mir docking mission. Classmates Clifford and Sega joined him on the nine-day flight aboard Atlantis. Searfoss commanded his third and final spaceflight, the 16-day STS-90 Neurolab mission aboard Columbia in 1998. Across his three missions, Searfoss logged 39 days in space. 

Ronald Sega 

Ohio native Sega graduated from the U.S. Air Force Academy and worked as a research associate professor of physics at the University of Houston when NASA selected him as an astronaut. On his first spaceflight, he served as a mission specialist aboard STS-60, the first Shuttle-Mir mission. The eight-day mission aboard Discovery took place in 1994. For his second and final spaceflight in 1996, Sega served as a mission specialist on STS-76, the third Shuttle-Mir docking mission. Fellow Hairballs Searfoss and Clifford also flew on the nine-day Atlantis mission. Across his two spaceflights, Sega logged 17.5 days in space. 

Nancy Sherlock Currie 

Born in Delaware, Sherlock grew up in Ohio and worked as a flight simulation engineer at JSC when NASA selected her as an astronaut. On her debut spaceflight, Sherlock flew as a mission specialist on STS-57, the first flight of the Spacehab module in 1993. Fellow classmates Voss and Wisoff joined her on the 10-day mission aboard Endeavour. On her subsequent missions, she flew under her married name of Currie. Her second trip into space took place in 1995, the nine-day STS-70 mission aboard Discovery. Classmate Thomas joined her on this mission to deploy the seventh TDRS satellite. On her third mission, Currie flew as a mission specialist on STS-88, the first space station assembly mission in 1998. Classmate Newman accompanied her on the 12-day Atlantis mission. For her fourth and final spaceflight in 2002, Currie flew on STS-109, the fourth Hubble Space Telescope servicing mission. Classmate Newman once again accompanied her on the 11-day Columbia mission. Across her four spaceflights, Currie logged nearly 42 days in space. 

Donald Thomas 

Ohio native Thomas earned a doctorate in materials science from Cornell University and worked as a materials science engineer at JSC when NASA selected him as an astronaut. For his first flight, he flew as a mission specialist on STS-65, the IML-2 mission aboard Columbia in 1994. Fellow Hairballs Halsell, Chiao, and Walz accompanied Thomas on the nearly 15-day flight, the longest shuttle mission up to that time. His second trip into space took place in 1995, the nine-day STS-70 mission aboard Discovery. Classmate Currie joined him on this mission to deploy the seventh TDRS satellite. Thomas flew his third spaceflight on STS-83 aboard Columbia, the MSL mission in 1997. Because managers cut the flight short after four days due to a fuel cell failure, NASA decided to fly the mission again, with the same crew, later in the year as STS-94, for the full 16-day mission duration. Classmates Halsell and Voss accompanied Thomas on both missions. Across his four missions, Thomas logged 43 days in space. 

Janice Voss 

Ohio native Voss earned a doctorate in aeronautics and astronautics from the Massachusetts Institute of Technology and worked as an integration manager at Orbital Science Corporation in Houston when NASA selected her as an astronaut. On her first spaceflight, Voss flew as a mission specialist on STS-57, the first flight of the Spacehab module in 1993. Fellow classmates Sherlock and Wisoff joined her on the 10-day mission aboard Endeavour. Voss flew as a mission specialist on her second spaceflight, the STS-63 Mir rendezvous mission in 1995, accompanied by classmates Collins and Harris. Voss flew as payload commander on her third spaceflight on STS-83 aboard Columbia, the MSL mission in 1997. Because managers cut the flight short after four days due to a fuel cell failure, NASA decided to refly the mission, with the same crew, later in the year as STS-94, for the full 16-day mission duration. Classmates Halsell and Thomas accompanied Voss on both missions. On her fifth and final spaceflight, Voss once again served as payload commander on STS-99, the Shuttle Radar Topography Mission. The 11-day mission aboard Endeavour took place in 2000. Over her five missions, Voss accumulated 49 days of spaceflight time. 

Carl Walz 

A native of Ohio, Walz worked as a flight test manager at the U.S. Air Force Flight Test Center in Nevada when NASA selected him as an astronaut. He received his first flight assignment as a mission specialist on STS-51, flying with fellow Hairballs Bursch and Newman on the 10-day flight aboard Discovery in 1993. Walz conducted a 7-hour 5-minute spacewalk with Newman to demonstrate future spacewalking techniques. For his second flight, he flew as a mission specialist on STS-65, the IML-2 mission aboard Columbia in 1994. Fellow Hairballs Halsell, Chiao, and Thomas accompanied Walz on the nearly 15-day flight, the longest shuttle mission up to that time. On his third trip into space, he served as a mission specialist on STS-79, the fourth Shuttle-Mir docking mission in 1996. Classmate Wilcutt served as pilot on the 10-day Atlantis mission. For his fourth and final spaceflight, Walz, along with fellow Hairball Bursch, spent 196 days in space as an Expedition 4 flight engineer aboard the space station in 2001 and 2002, conducting two spacewalks totaling 11 hours 50 minutes. He launched on STS-108 and returned on STS-111. Across his four missions, Walz logged more than 230 days in space and spent nearly 19 hours on three spacewalks. 

Terrance Wilcutt 

A native of Kentucky, Wilcutt served in the U.S. Marine Corps and worked as a test pilot at Naval Air Station Patuxent River when NASA selected him as an astronaut. Wilcutt served as pilot on his first spaceflight, STS-68, the 10-day SRL-2 Earth observation mission aboard Endeavour in 1994. Classmates Bursch, Jones, and Wisoff accompanied Wilcutt on the flight. He served as pilot on his second spaceflight, the STS-79 fourth Shuttle-Mir docking mission in 1996. Fellow Hairball Walz accompanied him on the 10-day Atlantis mission. Wilcutt commanded his third mission, STS-89, the eighth Shuttle-Mir docking mission. The nine-day flight aboard Endeavour took place in 1998. He commanded his fourth and final spaceflight in 2000, the STS-106 2A.2b space station assembly and logistics mission. The 12-day mission flew on Atlantis. Across his four missions, Wilcutt logged 42 days in space. He served as the NASA chief of Safety and Mission Assurance from 2011 to 2020. 

Jeff Wisoff 

Virginia native Wisoff earned a doctorate in applied physics from Stanford University and worked as an assistant professor at Rice University when NASA selected him as an astronaut. On his first spaceflight, Wisoff flew as a mission specialist on STS-57, the first flight of the Spacehab module in 1993. Fellow classmates Sherlock and Voss joined him on the 10-day mission aboard Endeavour. He participated in a 5-hour 50-minute spacewalk to demonstrate future spacewalking techniques. Wisoff served as a mission specialist on his second spaceflight, STS-68, the 10-day SRL-2 Earth observation mission aboard Endeavour in 1994. Classmates Bursch, Jones, and Wilcutt accompanied him on the flight. He served as a mission specialist on his third flight, STS-81, the fifth Shuttle-Mir docking mission in 1997. The 10-day flight took place aboard Atlantis. He flew his fourth and final mission on STS-92, the 3A space station assembly mission in 2000 that brought the Z1 truss to the facility. Wisoff participated in two spacewalks totaling 14 hours 3 minutes during the 13-day Discovery mission. Across his four spaceflights, Wisoff logged 44 days in space and spent nearly 20 hours on three spacewalks. 

David Wolf 

A native of Indiana, Wolf earned a medical degree from Indiana University and worked as an aerospace medical officer at JSC when NASA selected him as an astronaut. He received his first spaceflight assignment as a mission specialist on the STS-58 SLS-2 mission in 1993. Classmates Searfoss and McArthur accompanied him on the 14-day Columbia mission, at the time the longest space shuttle flight. For his second trip into space, he completed the 128-day NASA-6 long-duration mission as part of the Shuttle-Mir program in 1997 and 1998, launching aboard STS-86 and returning aboard STS-89. He participated in a 3-hour 52-minute spacewalk. He flew his third spaceflight as a mission specialist on the STS-112 9A space station assembly mission in 2002 that delivered the S1 truss to the orbiting lab. During the 11-day Atlantis mission, Wolf participated in three spacewalks totaling 19 hours 41 minutes. He completed his fourth mission on STS-127 in 2009, earning him the distinction as the last Hairball to make a spaceflight. During the 16-day Endeavour mission that delivered the Japanese module’s exposed pallet to the space station, Wolf participated in three spacewalks totaling 18 hours 24 minutes. Across his four spaceflights, Wolf logged more than 168 days in space and spent 42 hours on seven spacewalks. 

Summary

The NASA Group 13 astronauts made significant contributions to spaceflight. As a group, they completed 85 flights spending 1,960 days, or more than five years, in space, including one long-duration flight aboard Mir and five aboard the International Space Station. One Hairball made a single trip into space, three made two trips, one made three, 15 made four, and three went five times. Twenty-one members of the group contributed their talents on Spacelab or other research missions and three performed work with the great observatories Hubble and Chandra. Thirteen participated in the Shuttle Mir program, with 11 visiting the orbiting facility, one of them twice, another three times, and one completing a long-duration mission. Fifteen visited the International Space Station, five twice, participating in its assembly, research, maintenance, and logistics, with five completing long-duration missions aboard the facility. Eleven of the 23 performed 37 spacewalks spending 242 hours, or more than 10 days, outside their spacecraft.  

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NASA has selected David Korth as deputy for Johnson Space Center’s Safety and Mission Assurance directorate. Korth previously served as deputy manager of the International Space Station Avionics and Software Office at Johnson Space Center prior to serving as acting deputy for Safety and Mission Assurance.
 
I’m excited to embark on my new role as deputy for Johnson’s Safety and Mission Assurance directorate,” Korth said. “Safety has been a priority for me throughout my NASA career. It is at the forefront of every decision I make.”
 
Korth brings more than 34 years’ experience to NASA human space flight programs. Prior to supporting the space station Avionics and Software Office, Mr. Korth served as deputy manager of the program’s Systems Engineering and Integration Office where he also led the agency Commercial Destination program’s procurement culminating in the selection of Axiom Space.
 
Mr. Korth began his NASA career as an engineer in the space station program’s operations planning group where he helped develop initial operational concepts and planning system requirements for the orbiting laboratory. He converted to civil servant in 1998 and was among the first three individuals to achieve front room certification as a space station ‘OPS PLAN’ front room operator. Korth also served as the lead operations planner for Expedition 1 – the first space station crewed expedition, was awarded two NASA fellowships, served as the operations division technical assistant in the Mission Operations Directorate, and was selected as a flight director in May 2007and served as lead space station flight director for Expeditions 21, 22, and 37, lead flight director for Japanese cargo ship mission HTV3, and lead flight director for US EVAs 22, 23,and 27.

“David did an excellent job supporting Johnson’s many programs and institutional safety needs while serving as acting deputy manager,” said Willie Lyles, director of the Safety and Mission Assurance directorate. “He successfully weighed in on several critical risk-based decisions with the technical authority community. David’s program and flight operations experience is unique and is an asset to this role.” 
 
Throughout his career, Korth has been recognized for outstanding technical achievements and leadership, receiving a Rotary National Award for Space Achievement, a Silver Snoopy award, two Superior Achievement awards, two NASA Outstanding Leadership medals, and a NASA Exceptional Achievement medal.
 
“David is an outstanding leader and engineer who truly understands NASA’s safety environment and protocols,” said Vanessa Wyche, director of NASA’s Johnson Space Center. “His leadership will ensure the center continues its ‘safety first’ ideology. I am extremely pleased to announce his selection for this position.”
 
Mr. Korth earned his bachelor’s degree in aerospace engineering from Texas A&M University, and a master’s degree in statistics from the University of Houston-Clear Lake.

NASA has selected Mary Beth Schwartz as director of NASA’s Johnson Space Center Center Operations directorate. Schwartz previously served as the directorate’s deputy director.
 
“I’m excited to embark on my new role as director for Johnson’s Center Operations directorate,” Schwartz said. “It is an honor to lead an organization that is foundational to the center’s mission success.”
 
Ms. Schwartz began her NASA career as a NASA intern and has since held a variety of key roles. These include serving as a space shuttle flight controller, chair of the PSRP (Payload Safety Review Panel) for both the International Space Station and Space Shuttle programs, where she led establishment of PSRP franchises with international partners. She also served as the manager of the Safety and Mission Assurance business office, leading efforts in consolidation and budget integration, and as the associate director of Johnson engineering responsible for budget and facility functions.

Throughout her career, Schwartz has been recognized for her contributions to NASA, receiving the NASA Exceptional Service medal, as well as the NASA Honor and Silver Snoopy awards.

“Mary Beth has a unique perspective of Center Operations, not only as a mission and customer-focused organization, but as an organization that is key to employee experience,” said Vanessa Wyche, director of NASA’s Johnson Space Center. “I appreciate her vision for the organization, commitment to the mission, and overall genuine respect of the workforce. I am extremely pleased to announce her selection for this position.”
 
Ms. Schwartz earned her Bachelor of Science in Mechanical Engineering from the University of Houston.

This NASA Hubble Space Telescope image shows the planet Jupiter in a color composite of ultraviolet wavelengths. Released on Nov. 3, 2023, in honor of Jupiter reaching opposition, which occurs when the planet and the Sun are in opposite sides of the sky, this view of the gas giant planet includes the iconic, massive storm called the “Great Red Spot.” Though the storm appears red to the human eye, in this ultraviolet image it appears darker because high altitude haze particles absorb light at these wavelengths. The reddish, wavy polar hazes are absorbing slightly less of this light due to differences in either particle size, composition, or altitude.

Learn more about Hubble and how this type of data can help us learn more about our universe.

Image credit: NASA, ESA, and M. Wong (University of California – Berkeley); Processing: Gladys Kober (NASA/Catholic University of America)

This NASA/ESA Hubble Space Telescope image peers into the dusty recesses of the nearest massive star-forming region to Earth, the Orion Nebula (Messier 42, M42). Just 1,500 light-years away, the Orion Nebula is visible to the unaided eye below the three stars that form the ‘belt’ in the constellation Orion. The nebula is home to hundreds of newborn stars including the subject of this image: the protostars HOPS 150 and HOPS 153.

These protostars get their names from the Herschel Orion Protostar Survey, conducted with ESA’s Herschel Space Observatory. The object visible in the upper-right corner of this image is HOPS 150: it’s a binary star system where two young protostars orbit each other. Each star has a small, dusty disk of material surrounding it. These stars gather material from their respective dust disks, growing in the process. The dark line that cuts across the bright glow of these protostars is a cloud of gas and dust falling in on the pair of protostars. It is over 2,000 times wider than the distance between Earth and the Sun. Based on the amount of infrared light HOPS 150 is emitting, as compared to other wavelengths it emits, the protostars are mid-way down the path to becoming mature stars.

Extending across the left side of the image is a narrow, colorful outflow called a jet. This jet comes from the nearby protostar HOPS 153, which is out of the frame. HOPS 153 is significantly younger than its neighbor. That stellar object is still deeply embedded in its birth nebula and enshrouded by a cloud of cold, dense gas. While Hubble cannot penetrate this gas to see the protostar, the jet HOPS 153 emitted is brightly and clearly visible as it plows into the surrounding gas and dust of the Orion Nebula.

The transition from tightly swaddled protostar to fully fledged star will dramatically affect HOPS 153’s surroundings. As gas falls onto the protostar, its jets spew material and energy into interstellar space, carving out bubbles and heating the gas. By stirring up and warming nearby gas, HOPS 153 may regulate the formation of new stars in its neighborhood and even slow its own growth.

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Media Contact:

Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD

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NASA International Space Apps Challenge Announces 2024 Global Winners

NASA Space Apps has named 10 global winners, recognizing teams from around the world for their exceptional innovation and collaboration during the 2024 NASA Space Apps Challenge. As the largest annual global hackathon, this event invites participants to leverage open data from NASA and its space agency partners to tackle real-world challenges on Earth and in space.

Last year’s hackathon welcomed 93,520 registered participants, including space, science, technology, and storytelling enthusiasts of all ages. Participants gathered at local events in 163 countries and territories, forming teams to address the challenges authored by NASA subject matter experts. These challenges included subjects/themes/questions in ocean ecosystems, exoplanet exploration, Earth observation, planetary seismology, and more.

The 2024 Global Winners were determined out of 9,996 project submissions and judged by subject matter experts from NASA and space agency partners.

“These 10 exceptional teams created projects that reflect our commitment to understanding our planet and exploring beyond, with the potential to transform Earth and space science for the benefit of all,” said Dr. Keith Gaddis, NASA Space Apps Challenge program scientistat NASA Headquarters in Washington. “The NASA Space Apps Challenge showcases the potential of every idea and individual. I am excited to see how these innovators will shape and inspire the future of science and exploration.”

You can watch the Global Winners Announcement here to meet these winning teams and learn about the inspiration behind their projects.

2024 NASA Space Apps Challenge Global Winners

Best Use of Science Award: WMPGang

Team Members: Dakota C., Ian C., Maximilian V., Simon S.

Challenge: Create an Orrery Web App that Displays Near-Earth Objects

Country/Territory: Waterloo,Canada

Using their skills in programming, data analysis, and visualization, WMPGang created a web app that identifies satellite risk zones using real-time data on Near-Earth Objects and meteor streams.

• Learn more about WMPGang’s SkyShield: Protecting Earth and Satellites from Space Hazards project

Best Use of Data Award: GaamaRamma

Team Members: Aakash H., Arun G., Arthur A., Gabriel A., May K.

Challenge: Leveraging Earth Observation Data for Informed Agricultural Decision-Making

Country/Territory: Universal Event, United States

GaamaRamma’s team of tech enthusiasts aimed to create a sustainable way to help farmers efficiently manage water availability in the face of drought, pests, and disease.

• Learn more about GaamaRamma’s Waterwise project

Best Use of Technology Award: 42 QuakeHeroes

Team Members: Alailton A., Ana B., Gabriel C., Gustavo M., Gustavo T., Larissa M.

Challenge: Seismic Detection Across the Solar System

Country/Territory: Maceió, Brazil

Team 42 QuakeHeroes employed a deep neural network model to identify the precise locations of seismic events within time-series data. They used advanced signal processing techniques to isolate and analyze unique components of non-stationary signals.

• Learn more about 42 QuakeHeroes’ project

Galactic Impact Award: NVS-knot

Team Members: Oksana M., Oleksandra M., Prokipchyn Y., Val K.

Challenge:  Leveraging Earth Observation Data for Informed Agricultural Decision-Making

Country/Territory: Kyiv, Ukraine

The NVS-knot team assessed planting conditions using surface soil moisture and evapotranspiration data, then created an app that empowers farmers to manage planting risks.

• Learn more about NVS-knot’s 2plant | ! 2plant project

Best Mission Concept Award: AsturExplorers

Team Members: Coral M., Daniel C., Daniel V., Juan B., Samuel G., Vladimir C.

Challenge: Landsat Reflectance Data: On the Fly and at Your Fingertips

Country/Territory: Gijón, Spain

AsturExplorers created Landsat Connect, a web app that provides a simple, intuitive way to track Landast satellites and access Landsat surface reflectance data. The app also allows users to set a target location and receive notifications when Landsat satellites pass over their area.

• Learn more about AsturExplorers’ Landsat Connect project

Most Inspirational Award: Innovisionaries

Team Members: Rikzah K., Samira K., Shafeeqa J., Umamah A.

Challenge: SDGs in the Classroom

Country/Territory: Sharjah, United Arab Emirates

Innovisionaries developed Eco-Metropolis to inspire sustainability through gameplay. This city-building game engages players in making critical urban planning and resource management decisions based on real-world environmental data.

• Learn more about Innovisionaries’ Eco-Metropolis: Sustainable City Simulation project

Best Storytelling Award: TerraTales

Team Members: Ahmed R., Fatma E., Habiba A., Judy A., Maya M.

Challenge: Tell Us a Climate Story!

Country/Territory: Cairo, Egypt

TerraTales shared stories of how Earth’s changing climate affects three unique regions: Egypt, Brazil, and Germany. The web app also features an artificial intelligence (AI) model for climate forecasting and an interactive game to encourage users to make eco-friendly choices.

• Learn more about TerraTale’s project

Global Connection Award: Asteroid Destroyer

Team Members: Kapeesh K., Khoi N., Sathyajit L., Satyam S.

Challenge: Navigator for the Habitable Worlds Observatory (HWO): Mapping the Characterizable Exoplanets in our Galaxy

Country/Territory: Saskatoon, Canada

Team Asteroid Destroyer honed in on exoplanets, utilizing data processing and machine learning techniques to map exoplanets based on size, temperature, and distance.

• Learn more about Asteroid Destroyer’s project

Art & Technology Award: Connected Earth Museum

Team Members: Gabriel M., Luc R., Lucas R., Mattheus L., Pedro C., Riccardo S.

Challenge: Imagine our Connected Earth

Country/Territory: Campinas, Brazil

Team Connected Earth Museum created an immersive virtual museum experience to raise awareness of Earth’s changing climate. An AI host guides users through an interactive gallery featuring 3D and 2D visualizations, including a time series on Earth and ocean temperatures, population density, wildfires, and more.

• Learn more about Connected Earth Museums’ project

Local Impact Award: Team I.O.

Team Members: Frank R., Jan K., Raphael R., Ryan Z., Victoria M.

Challenge: Community Mapping

Country/Territory: Florianópolis, Brazil

Team I.O. bridges the gap between complex Geographic Information Systems data and user-friendly communication, making critical environmental information accessible to everyone, regardless of technical expertise.

• Learn more about Team I.O.’s G.R.O.W. (Global Recovery and Observation of Wildfires) project

Want to take part in the 2025 NASA Space Apps Challenge? Mark your calendars for October 4 and 5! Registration will open in July. At that time, participants will be able to register for a local event hosted by NASA Space Apps leads from around the world. You can stay connected with NASA Space Apps on Facebook, Instagram, and X.

Space Apps is funded by NASA’s Earth Science Division through a contract with Booz Allen Hamilton, Mindgrub, and SecondMuse.

3 Min Read

NASA Scientists Find New Human-Caused Shifts in Global Water Cycle

In a recently published paper, NASA scientists use nearly 20 years of observations to show that the global water cycle is shifting in unprecedented ways. The majority of those shifts are driven by activities such as agriculture and could have impacts on ecosystems and water management, especially in certain regions.

“We established with data assimilation that human intervention in the global water cycle is more significant than we thought,” said Sujay Kumar, a research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and a co-author of the paper published in the Proceedings of the National Academy of Sciences.

The shifts have implications for people all over the world. Water management practices, such as designing infrastructure for floods or developing drought indicators for early warning systems, are often based on assumptions that the water cycle fluctuates only within a certain range, said Wanshu Nie, a research scientist at NASA Goddard and lead author of the paper.

“This may no longer hold true for some regions,” Nie said. “We hope that this research will serve as a guide map for improving how we assess water resources variability and plan for sustainable resource management, especially in areas where these changes are most significant.”

One example of the human impacts on the water cycle is in North China, which is experiencing an ongoing drought. But vegetation in many areas continues to thrive, partially because producers continue to irrigate their land by pumping more water from groundwater storage, Kumar said. Such interrelated human interventions often lead to complex effects on other water cycle variables, such as evapotranspiration and runoff.

Nie and her colleagues focused on three different kinds of shifts or changes in the cycle: first, a trend, such as a decrease in water in a groundwater reservoir; second, a shift in seasonality, like the typical growing season starting earlier in the year, or an earlier snowmelt; and third a change in extreme events, like “100-year floods” happening more frequently.

The scientists gathered remote sensing data from 2003 to 2020 from several different NASA satellite sources: the Global Precipitation Measurement mission satellite for precipitation data, a soil moisture dataset from the European Space Agency’s Climate Change Initiative, and the Gravity Recovery and Climate Experiment satellites for terrestrial water storage data. They also used products from the Moderate Resolution Imaging Spectroradiometer satellite instrument to provide information on vegetation health.

“This paper combines several years of our team’s effort in developing capabilities on satellite data analysis, allowing us to precisely simulate continental water fluxes and storages across the planet,” said Augusto Getirana, a research scientist at NASA Goddard and a co-author of the paper.

The study results suggest that Earth system models used to simulate the future global water cycle should evolve to integrate the ongoing effects of human activities. With more data and improved models, producers and water resource managers could understand and effectively plan for what the “new normal” of their local water situation looks like, Nie said.

By Erica McNamee
NASA’s Goddard Space Flight Center, Greenbelt, Maryland

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Planets around other stars need to be prepared for extreme weather conditions, according to a new study from NASA’s Chandra X-ray Observatory and ESA’s (European Space Agency’s) XMM-Newton that examined the effects of X-rays on potential planets around the most common type of stars.

Astronomers found that only a planet with greenhouse gases in its atmosphere like Earth and at a relatively large distance away from the star they studied would have a chance to support life as we know it around a nearby star.  

Wolf 359 is a red dwarf with a mass about a tenth that of the Sun. Red dwarf stars are the most common stars in the universe and live for billions of years, providing ample time for life to develop. At a distance of only 7.8 light-years away, Wolf 359 is also one of the closest stars to the solar system.

“Wolf 359 can help us unlock the secrets around stars and habitability,” said Scott Wolk of the Center for Astrophysics | Harvard & Smithsonian (CfA), who led the study. “It’s so close and it belongs to such an important class of stars – it’s a great combination.”

Because red dwarfs are the most prevalent types of stars, astronomers have looked hard to find exoplanets around them. Astronomers have found some evidence for two planets in orbit around Wolf 359 using optical telescopes, but those conclusions have been challenged by other scientists.  

“While we don’t have proof of planets around Wolf 359 yet, it seems very possible that it hosts multiple planets,” Wolk added. “This makes it an excellent test bed to look at what planets would experience around this kind of star.”

Wolk and his colleagues used Chandra and XMM to study the amounts of steady X-rays and extreme ultraviolet (UV) radiation – the most energetic type of UV radiation – that Wolf 359 would unleash on the possible planets around it.

They found that Wolf 359 is producing enough damaging radiation that only a planet with greenhouse gases like carbon dioxide in its atmosphere – and located at a relatively large distance from the star – would likely be able to sustain life.

“Just being far enough away from the star’s harmful radiation wouldn’t be enough to make it habitable,” said co-author Vinay Kashyap, also of CfA. “A planet around Wolf 359 would also need to be blanketed in greenhouse gases like Earth is.”

To study the effects of energetic radiation on the habitability of the planet candidates, the team considered the star’s habitable zone – the region around a star where liquid water could exist on a planet’s surface. 

The outer limit of the habitable zone for Wolf 359 is about 15% of the distance between Earth and the Sun, because the red dwarf is much less bright than the Sun. Neither of the planet candidates for this system is located in Wolf 359’s habitable zone, with one too close to the star and the other too far out.

“If the inner planet is there, the X-ray and extreme UV radiation it is subjected to would destroy the atmosphere of this planet in only about a million years,” said co-author Ignazio Pillitteri of CfA and the National Institute for Astrophysics in Palermo, Italy.

The team also considered the effects of radiation on as-yet undetected planets within the habitable zone. They concluded that a planet like the Earth in the middle of the habitable zone should be able to sustain an atmosphere for almost two billion years, while one near the outer edge could last indefinitely, helped by the warming effects of greenhouse gases.

Another big danger for planets orbiting stars like Wolf 359 is from X-ray flares, or occasional bright bursts of X-rays, on top of the steady, everyday output from the star. Combining observations made with Chandra and XMM-Newton resulted in the discovery of 18 X-ray flares from Wolf 359 over 3.5 days.

Extrapolating from these observed flares, the team expects that much more powerful and damaging flares would occur over longer periods of time. The combined effects of the steady X-ray and UV radiation and the flares mean that any planet located in the habitable zone is unlikely to have a significant atmosphere long enough for multicellular life, as we know it on Earth, to form and survive. The exception is the habitable zone’s outer edge if the planet has a significant greenhouse effect.

These results were presented at the 245^th meeting of the American Astronomical Society in National Harbor, Maryland, and are being prepared for publication in a journal. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.

Read more from NASA’s Chandra X-ray Observatory.

Learn more about the Chandra X-ray Observatory and its mission here:

https://www.nasa.gov/chandra

https://chandra.si.edu

News Media Contact

Megan Watzke
Chandra X-ray Center
Cambridge, Mass.
617-496-7998
mwatzke@cfa.harvard.edu

Lane Figueroa
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
lane.e.figueroa@nasa.gov

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NASA’s Pandora Mission One Step Closer To Probing Alien Atmospheres

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Pandora, NASA’s newest exoplanet mission, is one step closer to launch with the completion of the spacecraft bus, which provides the structure, power, and other systems that will enable the mission to carry out its work.

“This is a huge milestone for us and keeps us on track for a launch in the fall,” said Elisa Quintana, Pandora’s principal investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The bus holds our instruments and handles navigation, data acquisition, and communication with Earth — it’s the brains of the spacecraft.”  

Pandora, a small satellite, will provide in-depth study of at least 20 known planets orbiting distant stars in order to determine the composition of their atmospheres — especially the presence of hazes, clouds, and water. This data will establish a firm foundation for interpreting measurements by NASA’s James Webb Space Telescope and future missions that will search for habitable worlds.

“We see the presence of water as a critical aspect of habitability because water is essential to life as we know it,” said Goddard’s Ben Hord, a NASA Postdoctoral Program Fellow who discussed the mission at the 245th meeting of the American Astronomical Society in National Harbor, Maryland. “The problem with confirming its presence in exoplanet atmospheres is that variations in light from the host star can mask or mimic the signal of water. Separating these sources is where Pandora will shine.”

Funded by NASA’s Astrophysics Pioneers program for small, ambitious missions, Pandora is a joint effort between Lawrence Livermore National Laboratory in California and NASA Goddard.

“Pandora’s near-infrared detector is actually a spare developed for the Webb telescope, which right now is the observatory most sensitive to exoplanet atmospheres,” Hord added. “In turn, our observations will improve Webb’s ability to separate the star’s signals from those of the planet’s atmosphere, enabling Webb to make more precise atmospheric measurements.”

Astronomers can sample an exoplanet’s atmosphere when it passes in front of its star as seen from our perspective, an event called a transit. Part of the star’s light skims the atmosphere before making its way to us. This interaction allows the light to interact with atmospheric substances, and their chemical fingerprints — dips in brightness at characteristic wavelengths — become imprinted in the light.

But our telescopes see light from the entire star as well, not just what’s grazing the planet. Stellar surfaces aren’t uniform. They sport hotter, unusually bright regions called faculae and cooler, darker regions similar to sunspots, both of which grow, shrink, and change position as the star rotates.

Using a novel all-aluminum, 45-centimeter-wide (17 inches) telescope, jointly developed by Livermore and Corning Specialty Materials in Keene, New Hampshire, Pandora’s detectors will capture each star’s visible brightness and near-infrared spectrum at the same time, while also obtaining the transiting planet’s near-infrared spectrum. This combined data will enable the science team to determine the properties of stellar surfaces and cleanly separate star and planetary signals.

The observing strategy takes advantage of the mission’s ability to continuously observe its targets for extended periods, something flagship missions like Webb, which are in high demand, cannot regularly do.

Over the course of its year-long prime mission, Pandora will observe at least 20 exoplanets 10 times, with each stare lasting a total of 24 hours. Each observation will include a transit, which is when the mission will capture the planet’s spectrum. 

Pandora is led by NASA’s Goddard Space Flight Center. Lawrence Livermore National Laboratory provides the mission’s project management and engineering. Pandora’s telescope was manufactured by Corning and developed collaboratively with Livermore, which also developed the imaging detector assemblies, the mission’s control electronics, and all supporting thermal and mechanical subsystems. The infrared sensor was provided by NASA Goddard. Blue Canyon Technologies provided the bus and is performing spacecraft assembly, integration, and environmental testing. NASA’s Ames Research Center in California’s Silicon Valley will perform the mission’s data processing. Pandora’s mission operations center is located at the University of Arizona, and a host of additional universities support the science team.

By Francis Reddy
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Media Contact:
Claire Andreoli
301-286-1940
claire.andreoli@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.

For decades, scientists have tried in vain to accurately predict solar flares — intense bursts of light on the Sun that can send a flurry of charged particles into the solar system. Now, using NASA’s Solar Dynamics Observatory, one team has identified flickering loops in the solar atmosphere, or corona, that seem to signal when the Sun is about to unleash a large flare.

These warning signs could help NASA and other stakeholders protect astronauts as well as technology both in space and on the ground from hazardous space weather.

Led by heliophysicist Emily Mason of Predictive Sciences Inc. in San Diego, California, the team studied arch-like structures called coronal loops along the edge of the Sun. Coronal loops rise from magnetically driven active regions on the Sun, where solar flares also originate.

The team looked at coronal loops near 50 strong solar flares, analyzing how their brightness in extreme ultraviolet light varied in the hours before a flare compared to loops above non-flaring regions. Like flashing warning lights, the loops above flaring regions varied much more than those above non-flaring regions.

“We found that some of the extreme ultraviolet light above active regions flickers erratically for a few hours before a solar flare,” Mason explained. “The results are really important for understanding flares and may improve our ability to predict dangerous space weather.”

Published in the Astrophysical Journal Letters in December 2024 and presented on Jan. 15, 2025, at a press conference during the 245th meeting of the American Astronomical Society, the results also hint that the flickering reaches a peak earlier for stronger flares. However, the team says more observations are needed to confirm this link.

Other researchers have tried to predict solar flares by examining magnetic fields on the Sun, or by looking for consistent trends in other coronal loop features. However, Mason and her colleagues believe that measuring the brightness variations in coronal loops could provide more precise warnings than those methods — signaling oncoming flares 2 to 6 hours ahead of time with 60 to 80 percent accuracy.

“A lot of the predictive schemes that have been developed are still predicting the likelihood of flares in a given time period and not necessarily exact timing,” said team member Seth Garland of the Air Force Institute of Technology at Wright-Patterson Air Force Base in Ohio.

Each solar flare is like a snowflake — every single flare is unique.

Kara kniezewski

Air Force Institute of Technology

“The Sun’s corona is a dynamic environment, and each solar flare is like a snowflake — every single flare is unique,” said team member Kara Kniezewski, a graduate student at the Air Force Institute of Technology and lead author of the paper. “We find that searching for periods of ‘chaotic’ behavior in the coronal loop emission, rather than specific trends, provide a much more consistent metric and may also correlate with how strong a flare will be.”

The scientists hope their findings about coronal loops can eventually be used to help keep astronauts, spacecraft, electrical grids, and other assets safe from the harmful radiation that accompanies solar flares. For example, an automated system could look for brightness changes in coronal loops in real-time images from the Solar Dynamics Observatory and issue alerts.

“Previous work by other researchers reports some interesting prediction metrics,” said co-author Vadim Uritsky of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the Catholic University of Washington in D.C. “We could build on this and come up with a well-tested and, ideally, simpler indicator ready for the leap from research to operations.”

By Vanessa Thomas
NASA’s Goddard Space Flight Center, Greenbelt, Md.

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Elton W. Miller, chief of aerodynamics at what is now NASA’s Langley Research Center in Hampton, Virginia, stands in the entrance cone of the Propeller Research Tunnel in this Sept. 9, 1926, photo. In front of the entrance is the Sperry M-1 Messenger, the first full-scale airplane tested in the tunnel.

The Propeller Research Tunnel, or PRT as it came to be known, was only the National Advisory Committee for Aeronautics’ third wind tunnel and the largest one built. The PRT was in fact the largest tunnel built at that time anywhere in the world. Designed to accommodate a full-scale propeller, the throat of the PRT was 20 feet in diameter.

Learn more about the PRT from the report originally published in December 1928.

Image credit: NASA