For all the heady talk about misleadingly “deific,” recently confirmed quantum specks named after Scottish physicists, another kind of historic event just transpired: a record-shattering laser beam that, in a single shot fired on 5 July 2012, generated more power than the United States does at any single instant.
Spooky or astonishing? How about both. Think of it as “extreme sports science”, a kind of lab-based game of automatic one-upmanship where researchers fiddle with incredibly complex, painstakingly calibrated machinery to produce unprecedented results— then outdo them.
That’s what the National Ignition Facility— home to the world’s largest laser— just did when it pulled the trigger on 192 beams of optically amplified, electromagnetic radiation-emitting light, all fired within a few trillionths of a second of each other, to deliver 500 trillion watts (or terawatts) of “peak power” and 1.85 megajoules of ultraviolet laser light.
Framed in more eye-catching terms: The NIF says 500 terawatts outpaces the entire US for power used “at any instant in time”, and that 1.85 megajoules amounts to roughly 100 times what any other laser produces regularly. No wonder those two power unit prefixes (tera, mega) come from Greek words meaning “monster” and “great.”
Then again, what else would you expect from a laser housed in a building the size of three football fields, or a science lab with a word like “ignition” in its moniker?
The NIF, located in Livermore, California, came online in March of 2009, and its goals are manifold: its primary mission, given funding by the National Nuclear Security Administration (NNSA)— “a semi-autonomous agency within the Department of Energy responsible for enhancing national security through the application of nuclear science to the nation’s national security enterprise”— is to duplicate what happens in contemporary nuclear weapons, in part to render underground nuclear testing unnecessary.
But it’s also a repository for scientists— the same sort that poke around at sub-sub-atomic levels for elemental quantum particles— looking to understand “extreme states of matter that exist in the centers of planets, stars, and other celestial objects”.
And last but not least— well beyond the holster-loaded conventions of mere pulp sci-fi skirmishing— the NIF laser is about puzzling out something called “fusion ignition”: the point at which nuclear fusion reactions become self-sustaining, to, in the NIF’s words, “provide abundant and sustainable clean energy”.
Fusion reaction is arguably the most exciting of the NIF’s goals: to catalyze self-sustaining nuclear fusion, wherein two light atomic nuclei “fuse” together and produce a single heavier nucleus while converting some of that mass to incredible amounts of energy. That, in so many words, is how stars are born, and it’s something scientists have been working to achieve since the 1950s.
The five-hundred-terawatt shot on 5 July brings scientists closer to solving a longstanding physics challenge and arguably the field’s holy grail: getting back more energy than you give. “The 500 TW shot is an extraordinary accomplishment by the NIF Team, creating unprecedented conditions in the laboratory that hitherto only existed deep in stellar interiors,” said MIT physicist Dr. Richard Petrasso in a statement on the NIF’s site. “For scientists across the nation and the world who, like ourselves, are actively pursuing fundamental science under extreme conditions and the goal of laboratory fusion ignition, this is a remarkable and exciting achievement.”
The 5 July shot was actually the NIF’s third in a series of test fires, a series that’s seen power ramped up by nearly 100 terawatts since 15 March, when the NIF fired a shot that delivered 1.8 megajoules and peak power of 411 terawatts.
And while electricity produced by sustained, controlled fusion reactions may not be commercially viable, well, ever, depending whom you talk to— some say thirty to forty years; others say indefinitely given the technical challenges of putting star-stuff in a container— the 5 July laser shot appears to be a major step forward.
“NIF is becoming everything scientists planned when it was conceived over two decades ago,” said NIF Director Edward Moses of the 5 July shot. In January of 2012, Moses predicted that fusion ignition would happen “in the next six to eighteen months”.
We’re getting close, in other words, to what you might call “the end of the beginning” of the very long (and expensive: an experimental international fusion reactor being built in France is said to cost sixteen billion euros, or nearly twenty billion dollars) road to theoretically limitless energy generation.
Rico says twenty billion dollars will seem like chump change if they pull this off...
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