http://web.mit.edu/newsoffice/2008/ldx-tt0319.htmlMIT tests unique approach to fusion power
Mimicking Earth's magnetic field in a giant thermos bottle
David Chandler, MIT News Office
March 19, 2008
An MIT team has successfully tested a novel reactor that could chart a new path toward nuclear fusion, which could become a safe, reliable and nearly limitless source of energy.
After 10 years of design, construction and testing, the reactor achieved full operation for the first time last November. Some of the equipment used to monitor its performance wasn't working then, so another test run scheduled for this week is expected to produce data needed for the first formal report on the experimental results.
Fusion--the process that provides the sun's energy--occurs when two types of atoms fuse, creating a different element (typically helium) and releasing energy. The reactions can only occur at extremely high temperatures and pressures. Because the material is too hot to be contained by any material, fusion reactors work by holding the electrically charged gas, called plasma, in place with strong magnetic fields which keep it from ever touching the walls of the device.
The new reactor, called the Levitated Dipole Experiment, or LDX, reproduces the conditions necessary for fusion by imitating the kind of magnetic field that surrounds the planets Earth and Jupiter. A joint project by MIT and Columbia University, it consists of a supercooled, superconducting magnet about the size and shape of a large truck tire. When the reactor is in operation, this half-ton magnet is levitated inside a huge vacuum chamber, using another powerful magnet above the chamber to hold it aloft.
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