We are literally surrounded by the cold cryogenic vacuum of space. And it’s only 62 miles (100 km) away! That should be incredibly unsettling.

 

People often ask both why and how I ended up focusing my career on a niche area like cryogenic hydrogen. To be honest, I had no idea that cryogenics was even a field of research, like the vast majority of engineering and physics students graduating from our universities. I started down this path by accident when my Master’s Thesis Advisors at the University of Idaho, Dr. Richard Jacobsen and Dr. Steve Penoncello, gave me the option in the Fall of 2005 to either write new equations of state for hydrogen or natural gas distribution. I chose hydrogen, because of rockets, like most young engineers would’ve. As you’re about to find out, I’m really glad I did — and just so you know, there’s plenty of room in this field for you too if you’re interested.

As I dove into researching hydrogen properties a new word kept coming up, “cryogenics”. Initial thoughts of frozen brains and dead bodies came to mind. Reality though is that cryogenics is the study of anything below 130 K in temperature, which includes most of space. Cryogenics is so incredible because it is a very simple and pure environment to observe the laws of the universe. If you’re interested in thermodynamics, heat transfer, and physics like me, cryogenics could be the field for you.

Early on during my Master’s thesis, I remember going into a meeting with Jacobsen and Penoncello. I had seen the words ‘orthohydrogen’ and ‘parahydrogen’ coming up over and over again and asked them what they were and how we were going to predict their ideal-gas properties. When Jacobsen, the US expert in equations of state, turned to Penoncello and said, “well we’ll have to call somebody about that.”

Penoncello said, “Well who?” ‘

Jacobsen said, “I don’t know, it’s a pretty small field.”

From that point forward I knew that I had an opportunity to became the expert on ortho- and parahydrogen; and given how much hydrogen was used by NASA and others, I’d have value. The behavior of hydrogen at cryogenic temperatures is amazing and I was hooked. That led to writing new property models for hydrogen. It was a big way to start a research career — write the equations that every other engineer or scientist working in the area would use.

It really wasn’t until the fall of 2007 that I had a chance to really get my hands on cryogenics. Dr. John Pfotenhauer and Dr. Greg Nellis had the only cryogenic hydrogen (really deuterium) project in the US. I accepted a research position, site unseen, thanks to my amazing friend Dr. Dave Rowe, who was touring Wisconsin and told me about the project. Pfotenhauer really taught me the fun of experimental cryogenics. Nellis taught me how to perform with cryogenic heat transfer and thermodynamics analysis. It was a perfect pairing.

While at Wisconsin I discovered the rich history of the Cryogenics field. Roger W. Boom originally started the cryogenics and applied superconductivity laboratory there in 1968. Although I never got to meet Dr. Boom as he was suffering Alzheimer’s and had moved away, I got to know Dr. Boom through the legacy of his accomplishments; primarily his great passion for developing students to enter into this field. He was so passionate about this legacy that he and his students created the Dr. Roger W. Boom Award, managed by the Cryogenic Society of America, for individuals under the age of 40 with promise to contribute to the fields of cryogenics and superconductivity. I got to meet Dr. Boom’s great niece and nephew at the Applied Superconductivity Conference recently. They described him as a gregarious and warm person who was always concerned with making sure everyone felt welcomed and involved with the community, and welcomed the successes of those around him. Although the Applied Superconductivity Laboratory left to become the National High Magnetic Field Laboratory at Florida State University, the Wisconsin Cryogenics lab remains the largest in academia in the US.

Dr. Boom passed away earlier this year. What he missed was the beginning of a cryogenic renaissance of sorts. Never in my lifetime has there been as much interest in space. With companies like Blue Origin, SpaceX, United Launch Alliance, and the new NASA Space Launch System (SLS) all offering commercial spaceflight capabilities, there’s never been more of a need or a better time for young engineers to develop cryogenic skills.

Most of these engineers with dreams of rockets don’t realize that those technologies have to perform missions almost entirely in the cold cryogenic vacuum of space. Most curricula don’t even define cryogenics or vacuum technologies. There’s a saying that’s often used, “Space is hard.” It’s because cryogenics and vacuum engineering is hard; actual rocket science.

Cryogenics is so hard that if you don’t have exceptional mentors and student engineers, you simply can’t do it. It’s shocking to realize how few labs in academia are working in this area and only producing a handful of graduates each year. That’s a big problem given the pressing need. So for this renewed interest to take hold it’s time for us in the cryogenics community to lean-in and rekindle Dr. Boom’s legacy. I’ve been very fortunate to have some of the best mentors and students imaginable. But it’s going to take many more following in the spirit of Dr. Boom’s legacy if we want to be serious as a nation about space.