Seeking Art in Science

The Neutron Express
Since 1999, scientists working on the National Spherical Torus Experiment at Princeton have investigated nuclear fusion — the source of the sun's energy — in hopes that the process can one day provide a clean, sustainable energy source on Earth. It could be used to power any number of machines, including, for instance, the commuter relatives of the toy train shown here. This model train was mounted with a synthetic radioisotope (a source of neutrons — or energy) and sent on a continuous three-day loop on hobby train tracks to help inform other fusion experiments.

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