The answer is carefully hidden right in the first sentence of the article: > The Korea Superconducting Tokamak Advanced Research (KSTAR), a superconducting fus

The answer is carefully hidden right in the first sentence of the article: > The Korea Superconducting Tokamak Advanced Research (KSTAR), a superconducting fusion device also known as the Korean artificial sun, set the new world record as it succeeded in maintaining the high temperature plasma for 20 seconds with an ion temperature over 100 million degrees. Tokamak here is a Russian for toroidal chamber with magnetic coils. The plasma is hold in place by interaction of magnetic fields from these coils with magnetic fields from currents flowing trough the plasma.