US scientists have produced a laser shot with an unprecedented energy level that could be a key step towards nuclear fusion, the US National Nuclear Security Administration said Wednesday.
The researchers for the first time delivered a megajoule of energy to a target by focusing 192 laser beams at the same time at a temperature of 111 million Celsius (200 million Fahrenheit), it said in a statement.
"Breaking the megajoule barrier brings us one step closer to fusion ignition," said the body's administrator Thomas D'Agostino in a statement.
"This milestone is an example of how our nation's investment in nuclear security is producing benefits in other areas, from advances in energy technology to a better understanding of the universe."
Nuclear fusion is the form of energy that powers the sun and stars and would provide a potentially clean and limitless alternative to dwindling fossil fuel reserves, but producing it in a controlled fashion has so far eluded scientists.
The US body said that in order to demonstrate fusion scientists focused the lasers into a cylinder the size of a pencil eraser containing a tiny targets filled with fuel containing deuterium and tritium, two isotopes of hydrogen.
The laser energy was converted into X-rays, which compressed the fuel until it reached high temperatures and pressures that are billions of times greater than Earth's atmospheric pressure, the statement said.
The process causes the hydrogen nuclei to fuse, releasing energy in a precursor to the fusion process.
By contrast, nuclear fission, which entails splitting the nucleus of an atom to release energy, remains dogged by concerns about safety and dangerously radioactive long-term waste.
Share This Article With Planet Earth
