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Record Setting 500 Trillion-Watt Laser Shot Achieved
cylonlover writes "Researchers at the Lawrence Livermore National Laboratory's National Ignition Facility (NIF) have achieved a laser shot which boggles the mind: 192 beams delivered an excess of 500 trillion-watts (TW) of peak power and 1.85 megajoules (MJ) of ultraviolet laser light to a target of just two millimeters in diameter. To put those numbers into perspective, 500 TW is more than one thousand times the power that the entire United States uses at any instant in time."
"To put those numbers into perspective, 500 TW is more than one thousand times the power that the entire United States uses at any instant in time."
Except for the instant when the lasers were on, of course.
Enough energy to send a DeLorean back to 1985 over 400,000 times.
This signature is false.
...and you could vaporize a human target from space.
... so, where did they get this amount of power? I hope they did not have to trickle load their capacitors for a whole year.
They plugged in a ZPM.
It's a bit more energy than that, but it's not a remarkable amount of energy. 1.85MJ is enough to turn just under 1L of water from 100C liquid phase to 100C vapour phase. ie - it's enough to boil 1L of water, if the water is already at the boiling point.
Latent heat of vapourization for H2O is about 2200 kJ/kg.
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correction: rubbing your hands together saying 'muahahaa'
Lasers are not normally used in Tokamak reactors. In those systems, the idea is to use magnetic fields to hold a plasma tight enough (and long enough) for fusion to initiate. The energy input (i.e. "heating") is done ohmically, that is, by radio waves that induce electric currents in the gas. The NIF pursues a different approach, called "inertial confinement fusion." The idea in these systems is to supply a whole load of energy in a very short time, so the hydrogen nuclei don't have time to move apart before the fusion reaction takes place. That is, their inertia is what confines them long enough for the reaction to go. In order to do this, you need a giant load of energy delivered into a very small volume in a very short time. That's why they quote the number as terawatts. The interesting part of this announcement is not just the TW energy rate, but the nanosecond-scale pulse width. This is actually pretty cool news...
Important difference: The LHC was built to be massively powerful because there were (apparently accurate) calculations of what would be needed. Ignition of a fusion reaction has been Real Soon Now for decades. Evidently, the theory behind nuclear fusion reactions is not nearly as good as that behind the Higgs boson. That is the point of my snarky remark.
Ignition of a fusion reaction was done a long time ago. The theory is sound. The problem was never theoretical. It is technical: how to keep the hot plasma contained without using up more power generating magnetic fields than the amount of power produced by the reaction. And then actually building such a containment devices with such powerful magnets that are flawless. And then finally making the device with such low tolerances that it could be feasible in a commercial environment and maintained with very long duty cycles and very little maintenance. which means materials that can resist gama rays for many years, and can be easily replaced and maintained etc. its a huge engineering problem -- not a scientific one.
Nuclear fusion has been real soon now for decades because the theory is so sound and so simple that its easy to underestimate the technical challenges.
No one has a right to their *own* opinion. They have a right to the TRUTH.