Years from now—maybe in a decade, maybe sooner—if all goes according to plan, the most complex machine ever built will be switched on in an Alpine forest in the South of France. The machine, called the International Thermonuclear Experimental Reactor, or ITER, will stand a hundred feet tall, and it will weigh twenty-three thousand tons—more than twice the weight of the Eiffel Tower. At its core, densely packed high-precision equipment will encase a cavernous vacuum chamber, in which a super-hot cloud of heavy hydrogen will rotate faster than the speed of sound, twisting like a strand of DNA as it circulates. The cloud will be scorched by electric current (a surge so forceful that it will make lightning seem like a tiny arc of static electricity), and bombarded by concentrated waves of radiation. Beams of uncharged particles—the energy in them so great it could vaporize a car in seconds—will pour into the chamber, adding tremendous heat. In this way, the circulating hydrogen will become ionized, and achieve temperatures exceeding two hundred million degrees Celsius—more than ten times as hot as the sun at its blazing core. 
 
 No natural phenomenon on Earth will be hotter. Like the sun, the cloud will go nuclear. The zooming hydrogen atoms, in a state of extreme kinetic excitement, will slam into one another, fusing to form a new element—helium—and with each atomic coupling explosive energy will be released: intense heat, gamma rays, X rays, a torrential flux of fast-moving neutrons propelled in every direction. There isn’t a physical substance that could contain such a thing. Metals, plastics, ceramics, concrete, even pure diamond—all would be obliterated on contact, and so the machine will hold the superheated cloud in a “magnetic bottle,” using the largest system of superconducting magnets in the world. Just feet from the reactor’s core, the magnets will be cooled to two hundred and sixty-nine degrees below zero, nearly the temperature of deep space. Caught in the grip of their titanic forces, the artificial earthbound sun will be suspended, under tremendous pressure, in the pristine nothingness of ITER’s vacuum interior. 
 
 For the machine’s creators, this process—sparking and controlling a self-sustaining synthetic star—will be the culmination of decades of preparation, billions of dollars’ worth of investment, and immeasurable ingenuity, misdirection, recalibration, infighting, heartache, and ridicule. Few engineering feats can compare, in scale, in technical complexity, in ambition or hubris. Even the ITER organization, a makeshift scientific United Nations, assembled eight years ago to construct the machine, is unprecedented. Thirty-five countries, representing more than half the world’s population, are invested in the project, which is so complex to finance that it requires its own currency: the ITER Unit of Account. 
 
 No one knows ITER’s true cost, which may be incalculable, but estimates have been rising steadily, and a conservative figure rests at twenty billion dollars—a sum that makes ITER the most expensive scientific instrument on Earth. But if it is truly possible to bottle up a star, and to do so economically, the technology could solve the world’s energy problems for the next thirty million years, and help save the planet from environmental catastrophe. Hydrogen, a primordial element, is the most abundant atom in the universe, a potential fuel that poses little risk of scarcity. Eventually, physicists hope, commercial reactors modelled on ITER will be built, too—generating terawatts of power with no carbon, virtually no pollution, and scant radioactive waste. The reactor would run on no more than seawater and lithium. It would never melt down. It would realize a yearning, as old as the story of Prometheus, to bring the light of the heavens to Earth, and bend it to humanity’s will. ITER, in Latin, means “the way.” 
 
 The main road to the ITER construction site from Aix-en-Provence, where I had booked a room, is the A51 highway. The drive is about half an hour, winding north past farmland and the sun-glittered Durance River. Just about every form of energy is in evidence nearby, from hydroelectric dams to floating solar panels. Seams of lignite, a soft brownish coal, run beneath the soil in Provence, but the deposits have become too expensive to mine. Several miles from Aix, a large coal plant, with a chimney that climbs hundreds of feet into the sky, is being converted to burn biomass—leaves, branches, and agricultural debris. ITER is being built a mile or two from the wooded campus of the Commissariat à l’Énergie Atomique et aux Énergies Alternatives, a state-funded research organization, created in 1945 to advance nuclear power, and now also renewable energy. Evergreen oak and Aleppo pine cover the foothills; beneath them, the French government maintains its largest strategic oil reserve. 
 
 ITER’s headquarters, a five-floor edifice, was erected two years ago. An undulating wave of gray concrete slats shade its floor-to-ceiling windows. Its interior is simple: whitewashed walls, polished-concrete floors. The building’s southern façade overlooks a work site, more than a hundred acres of construction on the opposite side of a berm. By the time the reactor is turned on—the formal target date for its first experiment is 2020—the site will be home to a small city. Nearly forty buildings will surround the machine, from cooling towers to a cryogenics plant, which will produce liquid helium to cool the superconducting magnets. A skywalk extends from the second floor of the headquarters to the berm, where a capacious NASA-style control room will one day be built. For now, the bridge ends in a pile of ochre dirt, and the only way to the vast expanse of construction is via a circuitous drive. ||||| Looking for news you can trust? 
 
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 The internet lit up this morning. The world was about to change dramatically for the better, all because of a major technological breakthrough: clean, abundant energy from nuclear fusion. “Lockheed Martin’s new fusion reactor can change humanity forever,” claims the headline in Gizmodo. A “potentially paradigm-shifting development in global energy,” says Aviation Week. Lockheed’s own promotional video for the Compact Fusion Reactor claims the company is “restarting the atomic age.” 
 
 Here are the key bits from the Reuters report Wednesday morning to bring you up to speed: 
 
 Tom McGuire, who heads the project, said he and a small team had been working on fusion energy at Lockheed’s secretive Skunk Works for about four years, but were now going public to find potential partners in industry and government for their work. Initial work demonstrated the feasibility of building a 100-megawatt reactor measuring seven feet by 10 feet, which could fit on the back of a large truck, and is about 10 times smaller than current reactors, McGuire told reporters. In a statement, the company, the Pentagon’s largest supplier, said it would build and test a compact fusion reactor in less than a year, and build a prototype in five years. 
 
 Lockheed Martin, one of the biggest military supply companies in the United States, says the technology could be deployed in as little as ten years. The company promoted the news with fanfare: 
 
 Being small is a big deal. See how compact fusion #energy will power the future: http://t.co/NCNREOYrv8 #fusionenergy pic.twitter.com/Ei9fQuG1PK — Lockheed Martin (@LockheedMartin) October 15, 2014 
 
 Rosi Reed, an assistant professor of physics at Wayne State University, and a researcher at the Large Hadron Collider, run by European Organization for Nuclear Research, said that the most impressive part of the breakthrough was the increase in energy output—ten times greater than that of previous reactors. “So this means that this reactor can be a lot smaller,” she said. 
 
 Of course, Reed said, while it’s exciting news, the promise is all theoretical at this stage. Should we believe the hype? 
 
 If there was a genuine breakthrough, said one nuclear physicist, “we’d be screaming from the treetops.” 
 
 First, let’s start with the basics. What is fusion? Stars—like our very own sun—create power in their cores using nuclear fusion. The conditions in the core of a star are very extreme—high pressures, temperatures, and densities. But “when we want to reproduce those conditions on Earth, we are at a great disadvantage,” says Dr. Swadesh M. Mahajan, a thermonuclear plasma physicist at the University of Texas. That’s because we don’t have the same immense mass as the sun. Our planet is far too small to produce the kind of gravity necessary for large scale fusion. The challenge, essentially, is putting the sun in a box. That box, in theory, is packed full of charged particles, moving at great speeds, constrained by a strong magnetic field that enhances the probability that the particles slam into each other. With enough pressure, the particles stop resisting, and finally fuse, let off an amazing amount of energy. 
 
 The problem, says Reed, is that usually it takes just as much energy to power that controlling magnetic field as the power you get from fusion, hence the current size of the reactors. Lockheed claims to be able to harness that energy at a more efficient rate, so it can then make the reactors smaller. 
 
 But there are a lot of reasons to be skeptical about Lockheed’s announcement, says Mahajan, who, with a team of scientists, designed a new way to reduce waste from nuclear reactors in 2009. First, fusion reactors right now are pretty big*. Mahajan says making them smaller is extremely hard to do—you need a very confined space, with loads of material at extremely high densities, and then you need to get that power out of the reactor to be used. “So it’s both the physics and the engineering which are extremely, extremely daunting,” he said. “We know of no materials that would be able to handle anywhere near that amount of heat.” 
 
 Mahajan called Lockheed’s announcement “poppycock.” He said, “Getting net energy from fusion is such a goddamn difficult undertaking,” he said. “We’re all aware that there’s always a finite chance of some breakthrough which is beyond the powers of imagination.” But if there was a genuine breakthrough, he said, “we’d be screaming from the treetops.” 
 
 Correction: An earlier version of this article wrongly said fusion reactors power some aircraft carriers and submarines. They are in fact “fission” reactors.
– Hoping scientists will find a brilliant alternative to oil and coal? How about a thermonuclear reactor that will hit temperatures ten times hotter than the sun and "could solve the world's energy problems for the next thirty million years," writes Raffi Khatchadourian in the New Yorker. The project—called the International Thermonuclear Experimental Reactor, in France—only needs to overcome rock-bottom morale, constant delays, tensions between engineers around the world, grumbling politicians, and a multi-billion-dollar budget that's never quite high enough. "There is a lot of anxiety here that it is all going to implode," says a physicist. Scientists have long dreamed of such a reactor to harness power by nuclear fusion, a cleaner process than fission that produces almost no radioactive waste. First proposed in 1985, ITER relies on an oft-squabbling, international cadre of experts who vie for the spotlight and struggle to convince politicians that it's still viable. The US has yanked and recommitted funding over the years, and a family-owned company in San Diego is building the all-important solenoid—in this case, a 20-mile-long cable wrapped around a metal column—to harness the plant's plasma in a "magnetic bottle" (because no physical material can contain it). But engineering challenges remain, and parts made around the world may or may not all fit together. If they do, Earth could have a new energy source in about 10 years. "I think ITER is an absolute necessity for the world—otherwise I wouldn't put up with the frustrations," says a top ITER official. Click for the full article, or see a Science Insider report on a damning assessment of ITER's management.