EAST, also known as China’s Artificial Sun, maintained a steady-state high-confinement plasma operation for 1000+ seconds reaching a temperature of 100 million °C.

• A tokamak is a machine that confines a plasma using magnetic fields in a donut shape to harness the energy of fusion.

Significance of this achievement: 

• Step towards fusion-based nuclear reactors which can act as alternatives to other sources of clean energy such as wind, solar etc.; 
• can address world energy crisis & problem of climate change

Advantage of nuclear fusion

• High Energy Output – It produces greater amounts of energy than any other source.
• Abundant & affordable fuel –It  uses cheap input materials, available in almost limitless supply.E.g., deuterium, tritium, hydrogen, Lithium
• Environmentally friendly – It has a zero-emission footprint and it does not contribute to greenhouse gas emissions or global warming
• Safe and Clean Process –  Fusion reactors produce helium, an inert gas. They also generate and recycle tritium, a radioactive substance with a short half-life. As a result, fusion does not produce long-lived radioactive nuclear waste.

Challenges in nuclear fusion

• Extreme Temperature Requirement: Fusion requires temperatures of hundreds of millions of degrees Celsius, even higher than the Sun’s core.
• Plasma containment: At such high temperatures, matter exists only in the plasma state (atoms get split into positively and negatively charged particles). Keeping plasmas stable in order to extract energy is difficult.
• Magnetic Confinement: The plasma must be suspended within a confined space using strong magnetic fields to prevent contact with reactor walls.