New Scientist reports on the latest equipment – a magnet stronger than any other – being sent from California to France for installation in ITER, the reactor that replicates the sun’s power to remake atoms:
The magnet, known as the central solenoid, is being shipped in parts and will be 18 metres tall, 4.2 metres wide and weigh around 1000 tonnes once fully constructed. With a magnetic field strength of 13 tesla, it will be about 280,000 times stronger than Earth’s own magnetic field. Because of this, the structure that the central solenoid sits in will have to withstand forces equal to twice the thrust of a space shuttle lift-off.
The magnet will be constructed from six modules, each containing 43 kilometres of coiled niobium-tin superconductors. Once these coils are in place, they will be sealed with 3800 litres of epoxy and shipped to the ITER construction site in France from the General Atomics factory in California. The first module leaves this month and the next will follow in August.
Unfortunately, the necessary temperatures of above 150 million °C would melt all known materials on Earth, so ITER will use powerful magnets to contain the reaction in a ring away from metal surfaces. Water pumped through the walls of the reactor will turn to steam and drive turbines to generate electricity. The central solenoid will generate a flow of reacting plasma around the ring, while other magnets will contain the plasma within the ring and adjust its shape.