SPACE.com Columnist Leonard David

Nuclear fusion breakthrough: What does it mean for space exploration?

NASA-funded fusion rocket design by University of Washington researchers.
(Image credit: University of Washington)

The announcement this week of fusion ignition is a major scientific advancement, one that is decades in the making. More energy was produced than the laser energy used to spark the first controlled fusion triumph. 

The result: replicating the fusion that powers the sun.

On Dec. 5, a team at Lawrence Livermore National Laboratory's National Ignition Facility (NIF) achieved the milestone. As noted by Kim Budil, director of the laboratory: "Crossing this threshold is the vision that has driven 60 years of dedicated pursuit — a continual process of learning, building, expanding knowledge and capability, and then finding ways to overcome the new challenges that emerged," Budil said.

The nuclear fusion feat has broad implications, fueling hopes of clean, limitless energy. As for space exploration, one upshot from the landmark research is attaining the long-held dream of future rockets that are driven by fusion propulsion. 

But is that prospect still a pipe dream or is it now deemed reachable? If so, how much of a future are we looking at?

Related: Major breakthrough in pursuit of nuclear fusion unveiled by US scientists

Data points

The fusion breakthrough is welcomed and exciting news for physicist Fatima Ebrahimi at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory in New Jersey. 

Ebrahimi said the NIF success is extraordinary.

"Any data points obtained showing fusion energy science achievement is fantastic! Fusion energy gain of greater than one is quite an achievement," Ebrahimi said. However, engineering innovations are still requisite for NIF to be commercially viable as a fusion reactor, she added.

Ebrahimi is studying how best to propel humans at greater speeds out to Mars and beyond. The work involves a new concept for a rocket thruster, one that exploits the mechanism behind solar flares

The idea is to accelerate particles using "magnetic reconnection," a process found throughout the universe, including the surface of the sun. It's when magnetic field lines converge, suddenly separate, and then join together again, producing loads of energy. By using more electromagnets and more magnetic fields, Ebrahimi envisions the ability to create, in effect, a knob-turning way to fine-tune velocity.

As for the NIF victory impacting space exploration, Ebrahimi said for space applications, compact fusion concepts are still needed. "Heavy components for space applications are not favorable," she said.

Physicist Fatima Ebrahimi in front of an artistic rendering of a fusion rocket. (Image credit: Elle Starkman, Princeton Plasma Physics Laboratory Office of Communications)

Necessary precursor

Similar in thought is Paul Gilster, writer/editor of the informative Centauri Dreams website. 

"Naturally I celebrate the NIF's accomplishment of producing more energy than was initially put into the fusion experiment. It's a necessary precursor toward getting fusion into the game as a source of power," Gilster told Space.com. Building upon the notable breakthrough is going to take time, he said.

"Where we go as this evolves, and this seems to be several decades away, is toward actual fusion power plants here on Earth. But as to space exploration, we then have to consider how to reduce working fusion into something that can fit the size and weight constraints of a spacecraft," said Gilster.

There's no doubt in Gilster's mind that fusion can be managed for space exploration purposes, but he suspects that's still more than a few decades in the future. 

"This work is heartening, then, but it should not diminish our research into alternatives like beamed energy as we consider missions beyond the solar system," said Gilster.

The target chamber of Lawrence Livermore National Laboratory's National Ignition Facility.

The target chamber of Lawrence Livermore National Laboratory's National Ignition Facility. (Image credit: Lawrence Livermore National Laboratory )

Exhaust speeds

Richard Dinan is the founder of Pulsar Fusion in the United Kingdom. He's also the author of the book "The Fusion Age: Modern Nuclear Fusion Reactors." 

"Fusion propulsion is a much simpler technology to apply than fusion for energy. If fusion is achievable, which at last the people are starting see it is, then both fusion energy and propulsion are inevitable," Dinan said. "One gives us the ability to power our planet indefinitely, the other the ability to leave our solar system. It's a big deal, really."

Exhaust speeds generated from a fusion plasma, Dinan said, are calculated to be roughly one-thousand times that of a Hall Effect Thruster, electric propulsion hardware that makes use of electric and magnetic fields to create and eject a plasma.

"The financial implications that go with that make fusion propulsion, in our opinion, the single most important emerging technology in the space economy," Dinan said.

Pulsar Fusion has been busy working on a direct fusion drive initiative, a steady state fusion propulsion concept that's based on a compact fusion reactor.

According to the group's website, Pulsar Fusion has proceeded to a Phase 3 task, manufacturing an initial test unit. Static tests are slated to occur next year, followed by an in-orbit demonstration of the technology in 2027.

Pulsar Fusion's Direct Fusion Drive, a compact nuclear fusion engine that could provide both thrust and electrical power for spaceships. (Image credit: Pulsar Fusion)

Aspirational glow

"The net energy gain reported in the press is certainly a significant milestone," said Ralph McNutt, a physicist and chief scientist for space science at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. "As more comes out, it will be interesting to see what the turning point was that pushed this achievement past the previous unsuccessful attempts," he said.

McNutt said that getting to a commercial electric power station from this recent milestone is likely to be a tough assignment. "But the tortoise did eventually beat the hare. Tenacity is always the virtue when one is handling tough technical problems."

With respect to space exploration, it certainly does not hurt in providing an example that great things can still be accomplished, McNutt said. 

"All of that said, it should be still a sobering thought that despite all of the work on NERVA/Rover there is still no working nuclear thermal rocket engine, and the promise of nuclear electric propulsion for space travel only had a brief glimmer with SNAP-10A in April of 1965," recalled McNutt. 

The actual use of ICF in a functional spacecraft has been a long-held dream, McNutt said, but that is very unlikely to change for a long time to come.

The cover of a 1989 NASA Lewis Research Center study on inertial confinement fusion propulsion. (Image credit: NASA)

"Space travel has always been tough. That NASA has 'blazed the trail' that many commercial entities are now following does not mean space has gotten easier, but the new ICF results have added to the aspirational glow on the horizon of the future," McNutt added. 

"That said, no one should be fooled into thinking that space will somehow not be tough someday. It's called 'rocket science,' with all that implies in popular culture for a reason," he concluded. 

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Leonard David
Space Insider Columnist

Leonard David is an award-winning space journalist who has been reporting on space activities for more than 50 years. Currently writing as Space.com's Space Insider Columnist among his other projects, Leonard has authored numerous books on space exploration, Mars missions and more, with his latest being "Moon Rush: The New Space Race" published in 2019 by National Geographic. He also wrote "Mars: Our Future on the Red Planet" released in 2016 by National Geographic. Leonard  has served as a correspondent for SpaceNews, Scientific American and Aerospace America for the AIAA. He was received many awards, including the first Ordway Award for Sustained Excellence in Spaceflight History in 2015 at the AAS Wernher von Braun Memorial Symposium. You can find out Leonard's latest project at his website and on Twitter.

  • bwana4swahili
    And producing 3.15MJ of output for 300+MJ is somehow a major breakthrough!? We're still a long, long, long way from anything useful!!
    Reply
  • Vernon Brechin
    In order to embrace the ground-based and spaced-based fusion concepts covered in this article one likely assumes that we have 20-30 years to turn this 'Titanic' around. Such dreamers typically have become masterful at excluding the following warnings from their consciousness.

    IPCC report: ‘now or never’ if world is to stave off climate disaster
    https://www.theguardian.com/environment/2022/apr/04/ipcc-report-now-or-never-if-world-stave-off-climate-disaster
    UN chief: World has less than 2 years to avoid 'runaway climate change'
    https://thehill.com/policy/energy-environment/406291-un-chief-the-world-has-less-than-2-years-to-avoid-runaway-climate * This statement was made 4-years ago.
    Reply
  • bwana4swahili
    Always gloom and doom, gloom and doom! Homo sapiens will adapt or die just as billions of species before them.
    Reply
  • Vernon Brechin
    bwana4swahili said:
    Always gloom and doom, gloom and doom! Homo sapiens will adapt or die just as billions of species before them.

    Many people have bought into the concept that we have a duty and an obligation to maintain an optimistic outlook despite the increasingly dire evidence coming from the broad spectrum of scientists, around the globe, that have been studying Anthropogenic Climate Disruption (ACD) effects for at least a half-century. That includes scientists studying both the physical and the biological aspects of ACD.
    Reply
  • Unclear Engineer
    There is nothing about the climate that is going to kill off all humans by 2025, 2050 or even 2100, even if we continue to emit more CO2 than we pledged. What will happen is that a lot of our coastal infrastructures will be inundated and need to be moved or replaced, and a lot of people will find their climate has changed - some for the worse and some for the better. In the long run, if we continue as we are doing, sea level will top out at about 300' higher than today.

    The predictions that Earth will become unfit for life are not likely outcomes, because there will be social feedbacks that force changes in our ways. The bigger issue is whether those changes result in wars over migration that will existentially threaten our species in the nearer term.
    Reply
  • Vernon Brechin
    Unclear Engineer said:
    There is nothing about the climate that is going to kill off all humans by 2025, 2050 or even 2100, even if we continue to emit more CO2 than we pledged. What will happen is that a lot of our coastal infrastructures will be inundated and need to be moved or replaced, and a lot of people will find their climate has changed - some for the worse and some for the better. In the long run, if we continue as we are doing, sea level will top out at about 300' higher than today.

    The predictions that Earth will become unfit for life are not likely outcomes, because there will be social feedbacks that force changes in our ways. The bigger issue is whether those changes result in wars over migration that will existentially threaten our species in the nearer term.

    I noticed a strong emphasis around the survivability of our own species. That is typical and often referred to as anthropocentric thinking. Despite your deep training in a specific field of physical science most likely you have a limited academic background in fields such as ecology, conservation biology and evolutionary biology. You likely were never immersed in the studies of how dependent human life is upon a diverse and healthy ecosystem of millions of other species. You likely are unaware that there are biochemical limits to the rate at which the higher lifeforms can evolve to meet changing climatic conditions. These are part of the input to the judgements made in the IPCC reports. They come from many thousands of peer reviewed scientific papers from a broad spectrum of scientific disciplines gathering evidence for at least the last half-century. The vast majority of the world's 8+ billion people are unaware of that so you are not alone in your views.
    Reply
  • Unclear Engineer
    Vernon, you are drastically underestimating my credentials and experience, as well as my interest in the natural ecosystems beyond just human comfort.

    So, please drop the attitude that I am naïve, undereducated or otherwise unaware about the things you are advocating.

    I have been actually involved in the issues we are discussing for decades, so this is much more than an academic exercise for me. And, I am well aware of the IPCC and other reports on global warming - I have been following the issues since the 1970s, and am updating the projected sea levels (and local land subsidence) for impacts on my home every time there is an update, as well as following the research on the ice sheets in Greenland and Antarctica to see how new knowledge is likely to affect those estimates. I am also working on a solar installation for my property. I am also involved in habitat restorations and preservations in my local area. I don't just post about things that matter, I get out and do things that I hope will matter.

    So, you are going to have to adopt a more balanced style for discussing the issues if you want to have any effect on my understanding of them. Trying to come across as possessing superior education, experience or knowledge isn't getting you any traction. Debate the issues with facts, please.
    Reply
  • Helio
    Vernon, ask yourself why RCP8.5 was replaced with RCP4.5? Climate modeling still doesn't have a strong grip on all the variables and how they affect climate, though it is critical that they keep improving this work.

    I like the use of the phrase, "climate sensitivity", to better address the real effort in climate modeling of all those variables, like the impact from CO2. Language is important and it has been abused. Consider how stupid the phrase "climate denier" sounds, which is, no doubt, intended as an ad hominem. I can't imagine anyone claiming there is no such thing as a climate?

    I wonder how many realize that more will die from cold than from heat in the next 12 months.? The CDC shows significantly more from cold in the US, which is based on death certificates. Other sources, however, say it is about even. Yet, world-wide, the mortality from cold is likely more than 5 to 1. here] Heat in the winter requires, currently, fossil fuels. Air conditioners made the south livable, also requiring fossil fuels. We are playing with lives of the vulnerable if we move off fossil fuels too quickly, and rhetoric suggests that's the direction being taken. Wind and solar can help but we must understand their limitations.

    More science, less hullabaloo.
    Reply
  • Helio
    Admin said:
    Nuclear fusion has broad implications, fueling hopes of clean, limitless energy and the long-held dream of future rockets that are driven by nuclear propulsion.

    Nuclear fusion breakthrough: What does it mean for space exploration? : Read more
    The part of the article revealing a prototype fusion propulsion is being built is very interesting!
    Reply
  • Unclear Engineer
    Yes, that is interesting. Pulsar Fusion has made other types of engines, but not fusion based, yet. See https://pulsarfusion.com/ .

    Considering that their website says "NUCLEAR FUSION SET TO BE THE WORLD’S DOMINANT POWER SOURCE BY 2100", I put them in the "advocate" category rather than the "objective forecaster" category.

    So, when I read "Pulsar has now proceeded to phase 3, the manufacture of the initial test unit. Static tests are to begin in 2023 followed by an In Orbit Demonstration (IOD) of the technology in 2027," I am hopeful but not overly optimistic. Research groups have been building fusion devices here on Earth for decades, and none are yet "continuous" or even close to it. True, an open system is much easier to run continuously than the closed systems that the other current projects hope to create for electric power production here on Earth's surface. "Containment" becomes "direction" in open systems designed to produce thrust. But, considering how slow the progress has been on other fusion projects, I will be amazed if Pulsar Fusion gets a successful orbital demonstration as early as 5 years from now.
    Reply