Diving Into Human Spaceflight Safety with NASA Johnson’s Craig Shannon

Diving Into Human Spaceflight Safety with NASA Johnson’s Craig Shannon

Growing up in Houston, Craig Shannon was always inspired by NASA and the spirit of exploration the agency represents. Yet it was a passion for scuba diving that unexpectedly led to his more than 23-year career at NASA’s Johnson Space Center.

Shannon became a certified diver and scuba instructor while earning his bachelor’s degree in communications from Stephen F. Austin State University. He happened to meet divers from NASA’s Neutral Buoyancy Laboratory (NBL) at a local environmental cleanup event during his senior year. “The encounter planted a seed,” he said.

A man wearing a black wetsuit floats with his head above water in a large swimming pool.
Craig Shannon during a dive in the Neutral Buoyancy Laboratory pool at NASA’s Johnson Space Center.
Image courtesy of Craig Shannon

Shannon was hired as an NBL diver shortly after graduation, launching what would become a 19-year career in dive operations. He progressed through a variety of roles – from utility diver, instructor, and training officer, to dive operations lead, training group lead, and ultimately, dive operations manager. “Each role deepened my understanding of operational excellence, safety, and leadership in high-performance environments,” he said. Shannon added that becoming the dive operations manager was one of the defining points of his career. “I had the privilege of leading an exceptional team and contributing directly to astronaut training and operational excellence.”

Seeking new challenges and opportunities for professional growth, Shannon transitioned to a test safety officer position at Johnson for about four years, expanding his knowledge of technical risk management in different environments. He returned to the NBL in 2025, this time as a safety officer. In that role, Shannon works to protect employees’ well-being and the facility’s operational integrity. His responsibilities are a mix of proactive safety initiatives – such as facility inspections, safety training, and communication – and incident response, which involves investigating mishaps and close calls and developing corrective action plans to prevent recurrence. He also serves as an internal technical consultant, fielding safety-related questions from employees and visitors and providing guidance that complies with Occupational Safety and Health Administration and NASA safety standards.

“I work across functions with operations, engineering, medical, and training teams to integrate safety into all daily processes and long-term planning,” he said. “It brings full circle my commitment to the safety and success of human spaceflight training.”

A man in a blue polo shirt inspects the spacesuit worn by another man.
Former NASA astronaut Mike Massimino helps Craig Shannon suit up for a suited test dive in the Neutral Buoyancy Laboratory pool.
Image courtesy of Craig Shannon

Shannon acknowledged that not having an engineering degree has made work more challenging at times, but it has not hindered his advancement. “I’ve earned key positions by committing myself to continuous learning, gaining in-depth knowledge of the technical areas I work in, and consistently demonstrating dedication to both my employers and my career,” he said. “My path has required hard work, adaptability, and a proactive approach to professional growth, which I view as strengths that have allowed me to contribute meaningfully in a highly technical setting.”

Shannon has also learned the importance of embracing change. “Change isn’t always easy, but it’s often where the most learning and development happen,” he said. “Whether it was stepping into leadership for the first time, shifting into a new field, or returning to a familiar place with a new purpose, each transition brought growth I never could have anticipated.” He added that patience, accountability, and empathy are important leadership qualities that help build stronger, more resilient teams.

While Shannon takes pride in his work, he said his family is his greatest achievement. “I’m most proud of raising three amazing children with my wife, Kimberley. They have been my grounding force and greatest inspiration,” he said.

A family of five - a man, wife, and their three children - stand on the sand of a Florida beach on a sunny day.
Craig Shannon, his wife Kimberley, and their three children enjoy family time at the beach in Florida.
Image courtesy of Craig Shannon

He is also the proud co-owner of a local scuba diving company, which allows him to combine his love for diving, travel, and community. “I’ve had the privilege of leading dive trips around the world with groups of amazing people—sharing unforgettable underwater experiences and fostering a strong, adventurous dive community,” he said. “It’s a way for me to stay connected to the roots of my diving career and continue exploring the world through the lens of curiosity and connection.”

He encourages the next generation to find something they are passionate about. “It’s important to be genuinely excited about what you do and to face the challenges ahead with determination and curiosity,” he said. “That energy, paired with a willingness to adapt and grow, has carried me through each phase of my career. Challenges will come, but how you meet them defines your path.”

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Linda E. Grimm

Reaching the Precipice in Angola 

Reaching the Precipice in Angola 

This satellite image centers on the serrated edge of the Huila plateau in Angola. The sheer cliff wall forms a rough C shape and is highlighted by dark shadows and a band of green vegetation. The lowlands to the left are tan-colored arid coastal plains, and the more-temperate plateau on the right side is greener.
June 19-20, 2025

In southwestern Angola, an expanse of coastal plains comes to an abrupt end at a natural barrier. The Huíla plateau soars above the lowlands to elevations of around 2,300 meters (7,500 feet). The sharp transition results in dramatic landscapes and a sudden change from an arid environment to more-temperate climes.  

The serrated edge of the Huíla plateau zigzags through this image, which is a mosaic of scenes acquired on June 19 and 20, 2025, with the OLI-2 (Operational Land Imager-2) and OLI on the Landsat 9 and Landsat 8 satellites, respectively. Areas around the plateau’s edges appear green with vegetation. But the landscape tends to look much browner by late September, at the end of the region’s dry season, during which almost no rain falls.  

This topography is part of the Great Escarpment of southern Africa, a 5,000-kilometer-long feature running roughly parallel to the continent’s edge. From Angola, it extends south through Namibia, across South Africa, and then northeast into Zimbabwe and Mozambique. The image below, acquired with the VIIRS (Visible Infrared Imaging Radiometer Suite) on the Suomi NPP satellite, shows a longer segment of the escarpment in Angola.  

A satellite image of southwestern Angola shows light-colored coastal desert to the left and a darker plateau to the right. These are separated by a jagged boundary tinged with green, part of the Great Escarpment of southern Africa. The Atlantic Ocean, mostly cloud-covered, runs along the left edge of the image.
June 20, 2025

Scientists believe the escarpment formed after the breakup of the supercontinent Gondwana in the Jurassic period. Since then, erosion has worn away at the continental margin such that the escarpment now sits 50 to 200 kilometers (30 to 120 miles) back from the coast.   

This Angolan section of the escarpment features dizzying, yet beautiful, landscapes. Tundavala Gap, a gouge eroded into the cliff line (below), is one of the most iconic with its well-framed view of the plains below. The precipice also presents a substantial obstacle to transportation. A stretch of the Namibe-Lubango Road overcomes this challenge with a series of scenic hairpin turns climbing to Serra da Leba pass near the town of Leba.  

Sheer cliff walls on the right and left sides of this photograph make a V shape in the foreground. Some light green shrubs grow from cracks in the rock. The ground visible in the opening between the cliffs is far below.
March 11, 2014

Lubango, one of Angola’s largest cities, occupies a valley on the Huíla plateau. In addition to its remarkable natural surroundings, the city boasts a diverse mix of cultures, striking architecture, and a wide variety of locally produced foods.  

NASA Earth Observatory images by Wanmei Liang, using Landsat data from the U.S. Geological Survey, and VIIRS data from NASA EOSDIS LANCE, GIBS/Worldview, the Suomi National Polar-orbiting Partnership, and the Joint Polar Satellite System (JPSS). Photo of Tundavala Gap © jbdodane.com. Story by Lindsey Doermann. 

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NASA’s IXPE Measures White Dwarf Star for First Time

NASA’s IXPE Measures White Dwarf Star for First Time

This artist’s concept depicts a smaller white dwarf star pulling material from a larger star, right, into an accretion disk. Earlier this year, scientists used NASA’s IXPE (Imaging X-ray Polarization Explorer) to study a white dwarf star and its X-ray polarization.
This artist’s concept depicts a smaller white dwarf star pulling material from a larger star, right, into an accretion disk. Earlier this year, scientists used NASA’s IXPE (Imaging X-ray Polarization Explorer) to study a white dwarf star and its X-ray polarization.
MIT/Jose-Luis Olivares

By Michael Allen 
 
For the first time, scientists have used NASA’s IXPE (Imaging X-ray Polarization Explorer) to study a white dwarf star. Using IXPE’s unique X-ray polarization capability, astronomers examined a star called the intermediate polar EX Hydrae, unlocking the geometry of energetic binary systems. 
 
In 2024, IXPE spent nearly one week focused on EX Hydrae, a white dwarf star system located in the constellation Hydra, approximately 200 light-years from Earth. A paper about the results published in the Astrophysical Journal. Astrophysics research scientists based at the Massachusetts Institute of Technology in Cambridge led the study, along with co-authors at the University of Iowa, East Tennessee State University, University of Liége, and Embry Riddle Aeronautical University. 
 
A white dwarf star occurs after a star runs out of hydrogen fuel to fuse in its core but is not massive enough to explode as core-collapse supernovae. What remains is very dense, roughly the same diameter as Earth with as much mass as our Sun.  
 
EX Hydrae is in a binary system with a main sequence companion star, from which gas is continuously falling onto the white dwarf. How exactly the white dwarf is accumulating, or accreting, this matter and where it arrives on the white dwarf depends on the strength of the white dwarf star’s magnetic field. 
 
In the case of EX Hydrae, its magnetic field is not strong enough to focus matter completely at the star’s poles. But, it is still rapidly adding mass to the accretion disk, earning the classification “intermediate polars. 

By Michael Allen

For the first time, scientists have used NASA’s IXPE (Imaging X-ray Polarization Explorer) to study a white dwarf star. Using IXPE’s unique X-ray polarization capability, astronomers examined a star called the intermediate polar EX Hydrae, unlocking the geometry of energetic binary systems.

In 2024, IXPE spent nearly one week focused on EX Hydrae, a white dwarf star system located in the constellation Hydra, approximately 200 light-years from Earth. A paper about the results published in the Astrophysical Journal. Astrophysics research scientists based at the Massachusetts Institute of Technology in Cambridge led the study, along with co-authors at the University of Iowa, East Tennessee State University, University of Liége, and Embry Riddle Aeronautical University.

A white dwarf star occurs after a star runs out of hydrogen fuel to fuse in its core but is not massive enough to explode as core-collapse supernovae. What remains is very dense, roughly the same diameter as Earth with as much mass as our Sun.

EX Hydrae is in a binary system with a main sequence companion star, from which gas is continuously falling onto the white dwarf. How exactly the white dwarf is accumulating, or accreting, this matter and where it arrives on the white dwarf depends on the strength of the white dwarf star’s magnetic field.

In the case of EX Hydrae, its magnetic field is not strong enough to focus matter completely at the star’s poles. But, it is still rapidly adding mass to the accretion disk, earning the classification “intermediate polars.

In an intermediate polar system, material forms an accretion disk while also being pulled towards its magnetic poles. During this phenomenon, matter reaches tens of millions of degrees Fahrenheit, bouncing off other material bound to the white dwarf star, creating large columns of gas that emit high-energy X-rays – a cosmic situation perfect for IXPE to study.

“NASA IXPE’s one-of-a-kind polarimetry capability allowed us to measure the height of the accreting column from the white dwarf star to be almost 2,000 miles high – without as many assumptions required as past calculations,” said Sean Gunderson, MIT scientist and lead author on the paper. “The X-rays we observed likely scattered off the white dwarf’s surface itself. These features are far smaller than we could hope to image directly and clearly show the power of polarimetry to ‘see’ these sources in detail never before possible.”

Information from IXPE’s polarization data of EX Hydrae will help scientists understand other highly energetic binary systems.

More about IXPE 

 The IXPE mission, which continues to provide unprecedented data enabling groundbreaking discoveries about celestial objects across the universe, is a joint NASA and Italian Space Agency mission with partners and science collaborators in 12 countries. It is led by NASA’s Marshall Space Flight Center in Huntsville, Alabama. BAE Systems, Inc., headquartered in Falls Church, Virginia, manages spacecraft operations together with the University of Colorado’s Laboratory for Atmospheric and Space Physics in Boulder. Learn more about IXPE’s ongoing mission here: 

https://www.nasa.gov/ixpe

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Lee Mohon

NASA Selects Tech Proposals to Advance Search-for-Life Mission

NASA Selects Tech Proposals to Advance Search-for-Life Mission

The letters NASA on a blue circle with red and white detail, all surrounded by a black background
Credit: NASA

NASA announced Monday the selection of industry proposals to advance technologies for the agency’s Habitable Worlds Observatory concept – the first mission that would directly image Earth-like planets around stars like our Sun and study the chemical composition of their atmospheres for signs of life. This flagship space telescope also would enable wide-ranging studies of our universe and support future human exploration of Mars, our solar system, and beyond.

“The Habitable Worlds Observatory is exactly the kind of bold, forward-leaning science that only NASA can undertake,” said NASA Administrator Jared Isaacman. “Humanity is waiting for the breakthroughs this mission is capable of achieving and the questions it could help us answer about life in the universe. We intend to move with urgency, and expedite timelines to the greatest extent possible to bring these discoveries to the world.”

To achieve its science goals, the Habitable Worlds Observatory would need a stable optical system that moves no more than the width of an atom while it conducts observations. The mission also would require a coronagraph – an instrument that blocks the light of a star to better see its orbiting planets – thousands of times more capable than any space coronagraph ever built. The Habitable Worlds Observatory would be designed to allow servicing in space, to extend its lifetime and bolster its science over time.

To further the readiness of these technologies, NASA has selected proposals for three-year, fixed-price contracts from the following companies:

  • Astroscale U.S. Inc., Denver
  • BAE Systems Space and Mission Systems, Inc., Boulder, Colorado
  • Busek Co. Inc, Natick, Massachusetts
  • L3 Harris Technologies Inc., Rochester, New York
  • Lockheed Martin Inc., Palo Alto, California
  • Northrop Grumman Inc., Redondo Beach, California
  • Zecoat Co. Inc., Granite City, Illinois

“Are we alone in the universe? is an audacious question to answer, but one that our nation is poised to pursue, leveraging the groundwork we’ve laid from previous NASA flagship missions. With the Habitable Worlds Observatory, NASA will chart new frontiers for humanity’s exploration of the cosmos,” said Shawn Domagal-Goldman, director of the Astrophysics Division at NASA Headquarters in Washington. “Awards like these are a critical component of our incubator program for future missions, which combines government leadership with commercial innovation to make what is impossible today rapidly implementable in the future.”

The newly selected proposals build on previous industry involvement, which began in 2017 under NASA’s “System-Level Segmented Telescope Design” solicitations and continued with awards for large space telescope technologies in 2024. The newly selected proposals will help inform NASA’s approach to planning for the Habitable Worlds Observatory concept, as the agency builds on technologies and lessons learned from its Hubble Space Telescope, James Webb Space Telescope, and upcoming Nancy Grace Roman Space Telescope.

To learn more about NASA’s Habitable Worlds Observatory, visit:

https://nasa.gov/hwo

-end-

Alise Fisher
Headquarters, Washington
202-358-2546
alise.m.fisher@nasa.gov

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Jan 05, 2026

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Tiernan P. Doyle

What’s Up: January 2026 Skywatching Tips from NASA

What’s Up: January 2026 Skywatching Tips from NASA

Jupiter beams bright, Saturn and the Moon cozy up, and the Beehive Cluster appears

Jupiter is at its biggest and brightest all year, the Moon and Saturn pair up, and the Beehive Cluster buzzes into view.

Skywatching Highlights

  • Jan. 10: Jupiter at opposition
  • Jan. 23: Saturn and Moon conjunction
  • Jan. (throughout): Beehive Cluster

Transcript

Jupiter is at its biggest and brightest

The Moon and Saturn share the sky 

And the beehive cluster makes an appearance 

That’s what’s up, this January

January 10, Jupiter will be at its most brilliant of the entire year! 

This night, Jupiter will be at what’s called “opposition,” meaning that Earth will be directly between Jupiter and the Sun. 

Jupiter at
NASA/JPL-Caltech

In this alignment, Jupiter will appear bigger and brighter in the night sky than it will all year – talk about starting off the new year bright! 

To see Jupiter at its best this year, look to the east and all evening long, you’ll be able to see the planet in the constellation Gemini. It will be one of the brightest objects in the night sky (only the moon and Venus will be brighter)  

Saturn and the Moon will share the sky on January 23rd as part of a conjunction!  

January 23 Conjunction
NASA/JPL-Caltech

A conjunction is when objects in the sky look close together even though they’re actually far apart. 

To spot the pair, look to the west and you’ll see Saturn just below the moon, sparkling in the night sky. 

The beehive cluster will be visible in the night sky throughout January!

The beehive cluster, more formally known as Messier 44, or M44, is made of at least 1,000 stars

It’s an open star cluster, meaning it’s a loosely-bound group of stars. There are thousands of open star clusters like the beehive in the Milky Way Galaxy! 

January 19 Beehive Cluster
NASA/JPL-Caltech

To see the beehive cluster, look to the eastern night sky after sunset and before midnight throughout the month – especially great nights to spot the cluster are around the middle of January when the cluster isn’t too high or low in the sky to see.   

With dark skies you might be able to spot the beehive with just your eyes, but binoculars or a small telescope will help. 

Here are the phases of the Moon for January.

What's Up January 2026 Moon Phases
NASA/JPL-Caltech

You can stay up to date on all of NASA’s missions exploring the solar system and beyond at science.nasa.gov.

I’m Chelsea Gohd from NASA’s Jet Propulsion Laboratory, and that’s What’s Up for this month.

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