China’s ‘Artificial Sun’ EAST Sets Fusion Record With 1,066-Second Plasma
China's experimental "artificial sun" has taken another important step toward the long-term goal of making fusion energy practical.
The Experimental Advanced Superconducting Tokamak, better known as EAST, maintained a high-confinement plasma for 1,066 seconds during an experiment in January 2025. The achievement set a new record for this type of operation and more than doubled EAST's previous 403-second record from 2023.
Located in Hefei, China, EAST is one of the world's major experimental devices for studying magnetic-confinement fusion.
Its latest result matters because producing extremely hot plasma is only part of the fusion challenge. Future fusion power plants would also need to keep that plasma stable and confined for long periods.
Why Is EAST Called an “Artificial Sun”?
The nickname comes from the process scientists are trying to reproduce.
The Sun generates energy through nuclear fusion. Under enormous temperature and pressure, light atomic nuclei combine to form heavier nuclei, releasing energy in the process.
Researchers hope that controlled fusion could eventually provide a powerful source of low-carbon energy on Earth.
Recreating the conditions needed for fusion, however, is extraordinarily difficult.
EAST uses a doughnut-shaped device known as a tokamak. Instead of allowing the superheated plasma to touch the walls of the machine, powerful magnetic fields are used to confine and control it.
That is essential because the temperatures involved are far beyond what any ordinary material could withstand in direct contact.
A 1,066-Second Record
On January 20, 2025, researchers operating EAST maintained steady-state high-confinement plasma for 1,066 seconds.
The plasma reached temperatures above 100 million degrees Celsius.
That duration is particularly significant. A future fusion power plant would need more than brief bursts of extremely hot plasma; it would need plasma that can remain stable and efficiently confined for much longer periods.
EAST had already demonstrated considerable progress in this area. In 2023, it maintained high-confinement plasma for 403 seconds. The 2025 experiment pushed that record to more than 17 minutes.
Why 100 Million Degrees?
The center of the Sun is roughly 15 million degrees Celsius, so why do experimental fusion devices on Earth aim for temperatures above 100 million degrees?
The answer lies in the very different conditions.
The Sun has enormous gravitational pressure helping nuclei overcome their natural electrical repulsion and fuse. Tokamaks on Earth cannot reproduce that gravitational pressure.
Instead, researchers compensate by heating plasma to much higher temperatures and using magnetic fields to keep it confined.
Reaching those temperatures is difficult, but keeping the plasma stable at the same time is an even greater engineering and physics challenge.
EAST Still Isn't a Fusion Power Plant
The record is impressive, but it is important to understand what it does — and does not — mean.
EAST did not suddenly become a commercial power station, nor does this experiment mean China can now supply electricity to homes using fusion.
EAST is an experimental research facility. Scientists use it to understand how extremely hot plasma behaves and how it can be controlled for increasingly long periods.
A practical fusion power plant would have to solve several additional challenges, including producing more usable energy than the complete system consumes over sustained operation, handling intense heat and particle loads, developing durable reactor materials, and converting fusion energy into reliable electricity.
The 1,066-second experiment addresses an important part of that much larger puzzle: long-duration, high-confinement plasma operation.
What Makes Fusion So Attractive?
Fusion has attracted scientific interest for decades because its potential advantages are enormous.
Unlike conventional nuclear fission, which splits heavy atomic nuclei, fusion joins light nuclei together.
The fuels considered for future fusion reactors could be sourced from relatively abundant materials, and the fusion process itself does not produce carbon dioxide during operation.
Fusion also differs from conventional nuclear fission in its reactor physics and waste profile, although a working fusion power plant would still face significant engineering, materials and radioactive-waste challenges.
The problem is that scientists have not yet turned controlled fusion into a commercially viable source of electricity.
EAST and the Global Fusion Effort
EAST is not working in isolation.
China is also a member of ITER, the enormous international fusion project under construction in southern France. ITER brings together China, the European Union, India, Japan, South Korea, Russia and the United States.
EAST and ITER are both based on magnetic-confinement fusion using tokamak technology, although the facilities have different designs and research goals.
Experiments on EAST can therefore provide valuable information about long-duration plasma operation and other challenges relevant to future fusion machines.
Scientists from EAST and ITER have already worked together on experiments designed to address technical and operational questions in fusion research.
A Step Forward, Not the Finish Line
Fusion research has a long history of impressive breakthroughs followed by difficult engineering challenges, so individual records need to be viewed in context.
EAST's 1,066-second plasma record does not mean commercially available fusion electricity is around the corner.
What it does show is that researchers are becoming increasingly capable of controlling extremely hot, high-confinement plasma for longer periods.
That is one of the capabilities a future fusion reactor will need.
After decades of research, the dream of harnessing the process that powers the Sun remains unfinished. EAST's latest record is another experimental step toward finding out whether that dream can eventually become a practical source of energy on Earth.
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