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Although the news of world affairs and politics has been rather bad lately, there is some more good news from the laboratory. Yesterday, an Oxford-based company, First Light Fusion, successfully tested a novel strategy to creating safe, sustainable nuclear fusion power (which is to say their test was a success–we have yet to see whether the larger concept fulfills its premise). Unlike the National Ignition Facility in California, which uses an enormous laser array to heat the hydrogen target to solar temperatures, or the ITER project (which uses a tokamak, a torus of plasma held in place by powerful magnetic fields), the British strategy is shockingly primitive–a gun shoots a super-high velocity projectile at a little cube containing two tiny spheres of deuterium. This cube is the secret ingredient for the company’s fusion plans (literally, since they hope to sell the proprietary fuel packets to everyone and make money that way).

Reading between the lines of the article announcing this information in “The Financial Times” it seems like this method does not produce as much energy as the tokamak or the laser array, however it is simpler and more scalable then those designs–if it can be made effective. So far none of the designs have produced more energy than they required, so that is quite a big if.

Coincidentally, although First Light Fusion is a British company, their main financial backer is an enormous shadowy Chinese capital company. Perhaps America’s legislators could spare some time from their busy schedule of performative white supremacy interrogations of Supreme Court candidates and suchlike culture wars gibberish to, you know, fund research into the technologies which will define the future.

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Hopefully you enjoyed the 2022 Winter Olympics! Whatever you may have thought about the participants or the hosts (or winter sports in general), I don’t think anybody could complain that the Beijing competitions lacked old-school Olympic drama. Now that I have had a relaxing fortnight of watching the contest (on the sofa, as far from winter as I can get), I will try to blog more regularly! First of all, let’s get to some overlooked news from a few weeks ago.

The good news of the world tends to get overlooked either because it is quotidian, or because it is esoteric/perplexing (with equally incomprehensible ramifications). This news bulletin definitely falls into the latter category! Remember previous posts about the National Ignition Facility, a colossal laser array at Lawrence Livermore Laboratory which is experimenting with alternate methods of initiating nuclear fusion? There has been a update or two since I first wrote about the place a dozen years ago (sigh), but thus far the lab has not produced the desired results. Suddenly, however, events on the ground are moving more swiftly.

The National Ignition Facility attempts to bypass costly and difficult mechanisms to reach nuclear fusion (like, you know, setting off nuclear fission bombs or building magnetic doughnuts the size of Malta) by concentrating a prodigious amount of energy at a tiny nuclear fuel capsule by means of an array of 192 super lasers all aimed at the tiny capsule (you should maybe imagine that this is being explained by someone with chaotic white hair and a German accent). Thus far, progress has been slow and incremental (at best). Four weeks ago, however, the researchers changed the size and shape of the capsule, and they achieved a new milestone on the road to nuclear ignition: a burning plasma, in which the fusion reactions themselves are the primary source of heating in the plasma.

In some ways this was the goal of the National Ignition Facility–to get more energy out of their process than they put into it. However, now that the experiments are starting to truly pay off, scientists will be working even harder to maximize energy output and efficiency and further optimize the encouraging results. Sadly, this potentially world-changing news, has received limited media attention (aside from within the pages of, you know, Nature and Ferrebeekeeper), however, I have a feeling that much more news will be forthcoming from Livermore. Hopefully some of this news will capture the public attention since prodigious energy breakthroughs are exactly what we need to break free of the prison of fossil fuel consumption which world society remains trapped within. We will keep you updated as more information becomes available, but for now, for the first time in a while we can at least fantasize of a world of abundant cheap energy which does not cause environmental devastation.

OK. the fantasizing is over, now go back to watching Russia use oil and gas to kick Germany (and its EU underling partners) around. Oh, maybe keep an eye on the rising global temperature too. Gee whiz, why aren’t we spending more money on ignition research?

Buried among today’s ghastly news stories was an interesting micro-nugget of potentially good news: the National Ignition Facility at Lawrence Livermore Lab in California managed to trigger a 1.35 Megajoule reaction by firing an ultraviolet laser array into a tiny target of nuclear fuel. Now Doc-Brown-style engineers/mad scientists might scoff at that number since 1.35 Megajoules is about the same amount of kinetic energy as in a Con Edison Truck rolling down a gentle hill. However the National Ignition Facility is meant to test colossal forces in tiny, manageable packages (it is putatively designed to model the extreme temperatures and conditions of nuclear weapons without requiring actual nuclear testing).

The real purpose of the National Ignition Facility is to try to leapfrog the moribund engineering quest for usable fusion energy. I wrote an overly optimistic piece about the place over a decade ago and have barely heard anything about it since then aside from a story about how they finally got their laser array to work right back in 2012. To briefly recap the methodology of this process, here is a simplified description. Scientists fire a burst of extremely intense energy through the futuristic laser array for 20 billionths of a second. This energy is theoretically meant to vaporize a small gold capsule containing deuterium and tritium. If lasers strike the gold correctly, the disintegrating gold releases a high-energy burst of x-rays which compact the capsule and force the hydrogen isotopes to fuse. On August 8th, for the first time, this process mostly worked and the reaction actually yielded 70% of the energy used to fire the lasers (an enormous improvement from the previous 3% maximum which had been the benchmark for years).

Apparently the breakthrough involved improving the size, shape, and microscopic surface preparation of the capsule (classic engineering stuff!). Nuclear engineers are quick to point out that the result still leaves us a long way from figuring out how to produce the clean abundant energy which humankind desperately needs to solve our (rapidly growing) problems and needs. Yet they also have a long-absent glint in their eyes and a new spring in their step. This is real progress in the search for a goal which has proven maddeningly elusive. Let’s keep an eye on the National Ignition Facility, and, maybe, just maybe this would be a worthy place to spend some more of our national budget.

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Many people complain that the news is all bad.  That is not true at all, but good news is sometimes harder to quantify or follow than bad tidings—plus human progress tends to be incremental.  I bring this up because this week did feature a good news story—and Ferrebeekeeper has been following along (as best we can) for years. The nuclear scientists at the National Ignition Facility (a part of Lawrence Livermore National Laboratory) have been attempting to use a vast laser array to heat/compress a deuterium and tritium fuel pellet to the extreme conditions necessary for nuclear fusion.

The container for the nuclear fuel

The container for the nuclear fuel

Nuclear fusion involves compressing/heating the elementary particles which make up atoms until the atoms fuse into new atoms.  Such a process releases outrageous amounts of energy but it does not start easily–indeed so much energy is required to begin the reaction that “hot” fusion typically requires a star or a nuclear fission detonator.  These items are dangerous and alarming to have lying around so scientists have been attempting to find a more controlled method of fusing atoms together.

The NIF Target Chamber

The NIF Target Chamber

Earlier this week the science journal Nature published a paper which details how NIF scientists finally managed to produce more energy than was initially put into the fuel pellet (albeit not into the overall system).  This does not sound overwhelmingly exciting—yet it is farther than nuclear engineers have got in 50 years.  To quote the amazingly named head scientist, Omar Hurricane, “We’ve assembled that stick of dynamite and we’ve gotten the fuse to light…If we can get that fuse to burn all the way to the dynamite, it’s going to pack a wallop.”

Just dream what we could accomplish with such energy!

Just dream what we could accomplish with such energy!

Abundant safe energy from nuclear fusion would be an astonishingly transformative innovation for humankind.  Immediately our principle economic and environmental problems would be forever altered.  Additionally having such a cosmic wellspring of energy available would allow us to embark on engineering works of a vastly greater scale than any known so far.

Planetary Engineering!

Planetary Engineering!

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Between giant planets and small stars exists a bizarre class of heavenly objects known as brown dwarfs. Brown dwarfs are not massive enough to fuse hydrogen elements together as do main sequence stars like the sun, however brown dwarfs larger than 13 Jovian masses are believed to fuse deuterium atoms and large brown dwarfs (65 Jovian masses and up) are believed to fuse lithium.  Since brown dwarfs can be very much like planets or like stars, there is a specific definition to describe the objects: a brown dwarf must have experienced some sort of nuclear fusion as a result of mass and temperature, however it cannot have fused all of its lithium (or it is considered a star or stellar fragment).  A stellar physicist reading this blog might object that medium and large stars have some lithium present in their outer atmosphere, or that a very young white dwarf could still have some unused lithium present, or even that an old heavy brown dwarf could have fused all of its lithium.  That physicist would be correct: she deserves some cookies and a pat on the head for poking holes in unnecessarily simple definitions.

Various Classifications of Brown Dwarfs

Various Classifications of Brown Dwarfs

Brown dwarfs were theorized to exist in the 1960s, but no astronomer managed to discover one until 1988 when a team of University of California astronomers who were studying white dwarfs found a bizarrely cool red spectral signature for a faint companion to the star GD 165.  Since then many brown dwarfs have been discovered and sorted into the major types M, L, T, and Y.  They occupy a strange ambiguous area at the bottom of the Hertzsprung-Russell diagram—objects which are luminous and massive in comparison to everything else but tiny and dim compared to real stars.

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There are some planets which are known to orbit brown dwarfs and there also brown dwarfs known to orbit true stars.  It is beginning to seem that there a great many brown dwarfs out there: perhaps they are as numerous as true stars (or maybe they are even more common than that).  Since they are hard to detect, scientists do not have a very accurate assay of their frequency in the universe.  The question bears somewhat on our understanding of the universe–since a great deal of matter is  not accounted for.

An artist's conception of a brown dwarf seem from a closely orbiting planet

An artist’s conception of a brown dwarf seem from a closely orbiting planet

My mind keeps returning to the fact that some brown dwarfs have planetary systems.  Imagine these melancholic twilight ice worlds forever orbiting a dim glow which will never blaze into a true sun.   It is a melancholy picture, but not without a certain beauty.

A Brown Dwarf with Planet and Moon (painting by Lynette Cook from fineartamerica.com)

A Brown Dwarf with Planet and Moon (painting by Lynette Cook from fineartamerica.com)

So, it is not easy to do what has never been done before. In October of 2010, I wrote about the National Ignition Facility, a joint scientific project run by Lawrence Livermore National Laboratory in Livermore California.  The National Ignition Facility aims to recreate the heat and pressure of stars and hydrogen bombs on a microscopic controlled scale.   The project is ostensibly designed as a United States defense project to model the nation’s next generation nuclear arsenal without use of (treaty-prohibited) nuclear testing, but cognoscenti have long suspected that it is a way that our country can pursue fundamental energy and physics research despite the apathy (or outright animosity) of a do-nothing congress and politically divided citizenry.

One of four banks of giant capacitors which power the laser microburst

Unfortunately the facility experienced a series of setbacks, and the massive laser array did not deliver the promised energy output.  However, this month all that changed!  On July 5th the facility briefly powered up its 192 lasers to deliver a 1.85-megajoule blast that released more than 500 trillion watts of power. Although the laser beam was only active for a miniscule fraction of a second, during that brief time it was focusing a thousand times more energy than the rest of the entire United States was actively using.  Remember Doc Brown from “Back to the Future” shouting about “1.21 gigawatts!” and desperately running his hands through his hair? Well, a gigawatt is a billion watts.  This laser beam produced a 500 terrawatt blast–500 trillion watts.  So just imagine Doc shouting “1.21 gigawatts!” four hundred thousand plus times!

The successful test firing brings the NIF within tantalizing reach of their desired ignition breakthrough—the glorious moment when scientists flip a switch and create a controlled, contained fusion reaction.  Building such a “star in a jar” is the first step on a road to titanic engineering and energy-creation achievements which could reshape humanity’s place in the universe.

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