Energy<\/p>\n
The 240-foot steel towers of an idle Wyoming wind farm toppled onto the prairie over two days, 450,000 pounds apiece, cut down with what the county fire chief called an exploding axe, a shaped charge notching the steel the way a logger notches a tree<\/p>\n
2 hours<\/p>\n
<\/a><\/p>\n Energy<\/p>\n An 85-foot nuclear reactor vessel filled with 654 cubic yards of concrete rode a self-propelled platform 2,000 feet down the road to a hall built to hold it alone, and the plan now is to wait 30 to 60 years, because the steel gets safer to cut every decade it sits<\/p>\n 3 hours<\/p>\n <\/a><\/p>\n Energy<\/p>\n An 8-foot clear column filled with 25% salt water let researchers watch how a nuclear battery would move its liquid fuel with no pump, heated by electric current pushed straight through the water, and the reactor it stood in for is designed to put out 20 megawatts of heat<\/p>\n 17 hours<\/p>\n <\/a><\/p>\n Energy<\/p>\n A 50-module power bank firing 50-megawatt bursts now feeds the plasma inside an Israeli fusion machine, five times the power of the 12-module bank before it, and its controller must keep all 50 acting as one source while the plasma changes the electrical load mid-pulse<\/p>\n 18 hours<\/p>\n <\/a>AI-generated summary from reviews, comparisons and articles by AutoNotion<\/p>\n Diamond has spent the better part of a century marketing itself as the toughest thing on Earth. Jewelers sell it as forever, machine shops use it to grind through everything else, and it sits at the top of every hardness chart you saw in school. So you\u2019d think that somewhere along the way, physics would\u2019ve pinned down the temperature at which the stuff finally gives up and melts.<\/p>\n Apparently not.<\/p>\n For about 20 years, lab measurements and computer simulations disagreed on diamond\u2019s melting point by roughly 20%, and the gap wouldn\u2019t close no matter how much computing power anyone threw at it. Theorists couldn\u2019t reproduce what the experimenters kept measuring, which is a frankly uncomfortable spot for a science to sit in.<\/p>\n That argument looks settled now. A team at Lawrence Livermore National Laboratory (LLNL) reported in Nature Physics<\/a> on August 13 that it shock-compressed tiny diamond samples until they melted, at around 12,680 \u00b0F (about 7,300 kelvin) and pressures up to 145 million psi (1 terapascal), and this time the measurement agreed almost perfectly with the quantum simulations. The lab\u2019s own earlier reading, it turns out, had been off by more than 1,000 degrees.<\/p>\n Marius Millot, the LLNL physicist who led the work, said in the lab\u2019s announcement<\/a> that the team got its samples \u201chotter than the surface of the sun\u201d and still measured temperature, density, atomic structure, and reflectivity before each one came apart. LLNL puts the pressure at roughly three times what you\u2019d find at the center of the Earth. Every reading had to land inside a billionth of a second, because that\u2019s how long the squeezed state held.<\/p>\n Melt point<\/p>\n 12,680 \u00b0F<\/p>\n Diamond\u2019s measured melting temperature near 145 million psi, about 7,300 kelvin.<\/p>\n Peak pressure<\/p>\n 145M psi<\/p>\n 1 terapascal, roughly three times the pressure at the center of the Earth.<\/p>\n Measurement window<\/p>\n 1 ns<\/p>\n The shocked state lasts a billionth of a second. Temperature, density, and atomic structure all get read inside it.<\/p>\n ACTIVE<\/p>\n OMEGA laser<\/p>\n 60 beams<\/p>\n 351-nm ultraviolet beams, up to 30 kilojoules on target, in a 10.8-foot chamber.<\/p>\n So how do you actually melt a diamond?<\/p>\n Not with an oven, that\u2019s for sure.<\/p>\n The experiments ran on the OMEGA laser at the University of Rochester\u2019s Laboratory for Laser Energetics<\/a>, which fires 60 ultraviolet beams into a target chamber 10.8 feet (3.3 meters) across. The beams start out as infrared light and get frequency-tripled to 351 nanometers on the way in. Together they can drop up to 30 kilojoules on a target in pulses lasting anywhere from 100 picoseconds to 4 nanoseconds. And it\u2019s the machine the US fusion community leans on as its workhorse, running experiments for national labs and universities from all over.<\/p>\n The beams flash-vaporize the surface of the target, and the material blasting off kicks a shock wave into the diamond underneath, the same way a rocket gets shoved forward by everything leaving out the back. Most of the diamond never sees laser light directly; it doesn\u2019t need to. That one wave squeezes and heats the sample in a single hit. A billionth of a second later, the whole thing comes apart.<\/p>\n Autonoci\u00f3n Newsletter<\/p>\n No spam. Unsubscribe anytime. Privacy policy (opens in new window)<\/a><\/p>\n You may be wondering how anyone reads atomic structure in a window that short. The answer is more lasers. A separate set of beams makes a flash of X-rays timed to go off while the shock is still moving through the diamond, and the way those X-rays scatter off the sample tells you whether the atoms are still holding a crystal pattern or they\u2019ve let go of each other. Optical instruments grab the temperature and the shock speed in the same instant.<\/p>\n Millot said this was the first time shock-compressed diamond had been watched with X-ray diffraction all the way up to melting, and the reason nobody managed it earlier is that carbon is a small, light atom that scatters very few X-rays, so the signal isn\u2019t much to work with.<\/p>\n Diamond floats on its own melt<\/p>\n The samples stayed diamond right up to the moment they melted, even at 145 million psi. Theory says carbon should switch into a denser crystal called BC8 somewhere around that pressure, and earlier shots on Sandia National Laboratories\u2019 Z machine had picked up hints of exactly that. These shots didn\u2019t find a trace of it. Millot\u2019s read is that a single shock doesn\u2019t leave the atoms time to rearrange, so the crystal stays trapped in the diamond structure until it turns liquid.<\/p>\n Frankly, the stranger result to me is how it melts. The team pinned the melt near 12,680 \u00b0F and watched the melting temperature drop slightly as the pressure climbed. When squeezing something harder makes it melt a little easier, that\u2019s the signature of a liquid that packs tighter than its own solid. Most materials do the opposite. Water pulls pretty much the same trick as diamond here, and that\u2019s why ice cubes float in your drink. Run that logic at 145 million psi and you get a sentence I didn\u2019t expect to type: a chunk of solid diamond floats on molten carbon.<\/p>\n Jon Eggert, the LLNL scientist whose experiments first pointed at that floating behavior about 20 years ago, has now watched it get confirmed directly by the diffraction data, along with the less flattering news that his original temperature measurement missed by more than 1,000 degrees. He called the correction exciting anyway, which strikes me as a pretty healthy way to take it.<\/p>\n Planetary scientists walk away with something too. Models suggest carbon can crystallize deep inside Neptune and Uranus and sink toward the core as diamond rain, and you can\u2019t exactly fly a probe down there to check. These experiments reached pressures beyond what those interiors hold, so the people modeling ice-giant planets now have measured numbers to anchor their math instead of extrapolations.<\/p>\n The fusion crowd has been waiting on this<\/p>\n Here\u2019s where it loops back to energy. At the National Ignition Facility (NIF), the world\u2019s largest laser, the fuel for its fusion shots rides inside a capsule made of diamond, and the implosion\u2019s first shock has to melt that shell into a smooth fluid. Any leftover solid lumps grow into flaws that can make the reaction fizzle. To make sure the shell melts, the lab\u2019s been hitting its capsules with a fairly strong first shock.<\/p>\n The new numbers say a gentler first shock would melt the shell just as completely. A gentler shock leaves the fuel more compressible, and more compression squeezes more energy out of the same laser. LLNL\u2019s simulations suggest the change could as much as triple the energy gain, though the lab hangs a condition on it: every other way an implosion can degrade has to stay under control first. That\u2019s a best-case number in my book, and fusion predictions have a pretty long history of taking their time.<\/p>\n There\u2019s a lot of motion around that machine right now anyway. A US startup says it can grow the smooth hydrogen fuel layer inside those capsules in two to three hours, a job NIF\u2019s own process spends days and sometimes a week on<\/a>, and a New Jersey shop just ran a flat fusion magnet to 6 tesla<\/a> chasing a completely different route to the same goal.<\/p>\n LLNL says the next round of diamond experiments runs on NIF itself, to watch how the capsule material behaves under a train of several shocks instead of one, and the lab hasn\u2019t put a date on any of it. Millot and his colleagues published the melting study in Nature Physics on August 13.<\/p>\n","protected":false},"excerpt":{"rendered":"KeysQuestions4Explore4 For two decades, physicists couldn’t agree on something as fundamental as when diamond melts \u2014 and the…\n","protected":false},"author":2,"featured_media":905307,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[24],"tags":[64,63,292,128],"class_list":["post-905306","post","type-post","status-publish","format-standard","has-post-thumbnail","category-physics","tag-au","tag-australia","tag-physics","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/905306","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=905306"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/905306\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/905307"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=905306"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=905306"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=905306"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"OMEGA](\"https:\/\/www.newsbeep.com\/au\/wp-content\/uploads\/2026\/09\/OMEGA-laser-target-chamber--1024x576.jpg\")
Laboratory for Laser Energetics \u2013 University of Rochester<\/p>\n