Temperatures in the hearts of stars are tens of millions of degrees — hot enough to “fuse” hydrogen atoms together to make helium. This process converts almost one percent of the hydrogen to energy, which makes a star shine.
Researchers have been trying for decades to re-create that process here on Earth, providing a source of safe, reliable power. So far, though, they haven’t had much luck.
They have created fusion in the lab, but the reactions can’t be sustained. That’s because the gas is so hot that it flies apart, and no bottle can hold it. Most experiments use powerful magnetic fields to try to contain the nuclear reactions. But so far, more energy goes into the fusion process than comes out.
Today, though, some scientists are trying a new approach using the Z machine at Sandia National Laboratories. It delivers a quick, powerful burst of electricity to create temperatures close to those inside stars. This burst of energy is combined with a high-power laser to heat the fuel and begin the fusion process. A magnetic field traps the particles created in the fusion reactions, so they feed back into the process and help sustain the reactions.
Even with the new approach, though, it’s likely to be many years before we’re lighting our homes and offices with electricity generated by nuclear fusion — the power source of the stars.
We’ll talk about how astronomers are using the Z machine to create the surfaces of stars tomorrow.
Script by Damond Benningfield, Copyright 2013
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