Michael Tonks, Ph.D., the new acting chair of the Department of Materials Science & Engineering, grew up in Los Alamos, NM – birthplace of the atomic bomb and a desert hub for top-secret research.
“My upbringing is weird,” Tonks said recently from his office at the University of Florida. “My dad worked his whole career at Los Alamos National Lab. Having a Ph.D. and being a scientist was normal. Most of the parents had Ph.D.’s. At the time, it was the highest per capita of Ph.D.’s in the world in that town.”
He knew his dad was a physicist, but because his work was classified, Tonks never really knew what he did.
These days on family visits to Los Alamos, Tonks and his father – who retired in 2012 – talk about equations, sometimes prompting Tonks’ siblings (one a Ph.D. in biophysics) to throw in theories and formulas to stir the numerical chaos. Complex equations are sometimes a part of family gatherings.
Weird? No. This is a logical origin story for an award-winning professor whose research is playing a key role in NASA’s quest for a crewed mission to Mars as early as 2030. For years, Tonks and his students have been researching rocket propulsion powered by heat from nuclear fission.
“Liquid hydrogen needs to be superheated and expand as fast as possible,” he explained. With the weight of carrying liquid hydrogen on the rocket, Tonks’ mission is to attain the safest and most efficient rocket propulsion.
“We need to get it as hot as possible, so they want to drive this fuel up to 3000 Kelvin,” he said. “That is the maximum temperature, which is half the temperature of the sun. And it’s above the melting temperature of almost all of the material we have, but not all.”
Tonks is seeking a correct mix to power the propulsion but also enhance safety and keep the integrity of the other materials on the rocket amid the nuclear superheat.
“With a power reactor, you need material that can take a lot of changes,” Tonks said.
Tonks’ degrees are in mechanical engineering. He became interested in nuclear propulsion during his seven years working at the Idaho National Lab, where he wrote a research proposal about using the tools developed for power reactors in space reactors at NASA.
Later, he started teaching and researching at Penn State, where NASA gave him $50,000 to prove the proposal was feasible. It was. By the time he started at UF in 2017, NASA was funding the project at a much larger level, he said.
“NASA’s fuel-development program needs a good concept that will operate well. NASA wants to have it all sorted out within 10 years,” Tonks said.
Challenges
You cannot duplicate space conditions on Earth, so there is no exact way to test it.
“We can do modeling assimilation (at UF) to start to predict how these materials are going to behave under these harsh conditions,” Tonks said. “That’s the reason this is attractive to NASA. It allows them to make faster development on materials they can’t test yet.”
How do we guarantee there is enough fuel to operate a reactor all the way to Mars and back?
“There was a big focus on fuel loss,” Tonks said.
Safety on the ground and in space. A Mars mission will have astronauts exposed to constant cosmic radiation.
“Part of this is getting people there as fast as possible because the trip will be highly dangerous due to cosmic radiation,” he said. “The less time, the better. The propulsion system is a big part of that, making it so we can decrease the time the astronauts have to be transporting between here and Mars.”
To be sure, Tonks is looking forward to the day when that crewed mission to Mars blasts off with the rocket fuel he helped refine. “But honestly,” he said, “there is a lot in between that I look forward to, as well. The first time they test this in a reactor is going to be really exciting.”
“Dr. Tonks has been an invaluable asset to our college, bringing not only exceptional expertise in the nuclear field but also a profound dedication to advancing research and education,” said Forrest Masters, Ph.D, interim dean for the Herbert Wertheim College of Engineering. “His leadership in the department has significantly elevated our program, fostering innovation and collaboration that resonate throughout the academic community.”
When Tonks is not teaching or dabbling in nuclear-powered rocket propulsion, he often can be found singing. He sang in the choir as a child, his college minor was music, and he has sung in the Gainesville Master Chorale. At a Get to Know Us faculty event at UF, he once sang “You’ll Be Back” from “Hamilton.”
His other hobby?
Step inside his office in Rhines Hall, and you will see an old manual typewriter and a globe. Take a closer look. They are made with LEGOs. Tonks is, and always has been, a LEGOs fanatic.
It’s a family passion, too.
“Our house is totally decorated in LEGOS. Think about a kitchen. You have the counters and the space up top where people usually put flowers. We have LEGO sets there,” said Tonks, husband to Margaret and father to Avery, 21, and Anna, 18. “We have this big treehouse set, a bunch of ‘Star Wars’ stuff – the big walkers and ships.”
In the family library, there is a LEGO set depicting Rivendell from “The Lord of the Rings,” as well as “realistic” LEGO flowers stationed throughout the house.
Tonks has been the associate chair of the Department of Materials Science & Engineering since 2019. He was promoted in July to acting chair.
“His contributions are a testament to his unwavering commitment and have profoundly enriched our institution’s legacy in nuclear science,” Masters said.