Physicists talk about recreating the heart of the sun at major exhibition

Scientists will be talking to visitors about how they hope to recreate the centre of the Sun at the upcoming Royal Society Summer Science Exhibition.

The Sun, like all stars, is composed of very hot and dense plasma. At the exhibition, a team of Imperial physicists will showcase research that attempts to recreate the conditions found in the core of the Sun, which is incredibly difficult to achieve as the Sun is 130 times denser than water and has a temperature of 14 million degrees Centigrade.

The researchers will also be talking about their work with US scientists on recreating on Earth the process that powers stars to provide a clean, safe, and zero-carbon supply of energy that will last for millions of years.

Describing the exhibit, Dr Arthur Turrell, from the Plasma Physics group at Imperial College London, said: “The process that powers stars, and the Sun, is called nuclear fusion. This is when two nuclei fuse together and produce energy. Our research is trying to understand how this energy is transported, in the form of light, from the centre of the Sun to the surface. Recreating and understanding the extreme conditions found at the centre of the Sun can only help us in our ultimate goal to harness star power on Earth to produce an almost unlimited source of energy.”

As part of the exhibition, Imperial physicists will showcase research they are carrying out with the Atomic Weapons Establishment where an academic access programme is allowing scientists to carry out ground breaking experiments on one of the world’s most powerful lasers called the Orion laser.

PhD student Oliver Pike from the Department of Physics at Imperial College London said: “The Sun is so hot and dense it would be impossible to send a probe into its core. Instead we are using the Orion laser, which is more powerful than the entire UK national power grid, to recreate the inside of the Sun. The laser is only on for one billionth of a second, but in that tiny amount of time we are able to create very similar conditions to the centre of the Sun.”

In this hands-on interactive exhibit, visitors will get a flavour of the important physics involved in these experiments. They will be able to play with plasma in a plasma globe, focus a laser through a lens to pop a balloon, and talk to the scientists about their research.

Imperial researchers were the early pioneers of nuclear fusion. In the 1940s Imperial physicist and Nobel Prize winner, Sir George Thompson, was the first to emulate stellar fusion by squeezing plasma. But in the 70 years since Thompson’s pioneering research, physicists have struggled to produce more energy than the experiments require to kick start them in the first place.

Dr Arthur Turrell said: “Mimicking the processes that power the Sun would transform our energy supply, if we can get it to work. Fusion reactions do not produce carbon dioxide, are incredibly safe, and produce little radioactive waste relative to fission. A single kilogram of fusion fuel used up in reactions releases the equivalent energy of a large wind turbine running for 11 years, or burning 50,000 barrels of oil. The energy released by fusion reactions, and its potential for energy, is extraordinary.”

Ask a question about this exhibit in a live Twitter chat on Monday 23 June 12:00-12:45 by tweeting @arthurturrell using the hashtag #asksummerscience.

The Royal Society Summer Science Exhibition ‘Set the controls for the heart of the sun’ runs from 1 to 6 July. More stories on Imperial’s other exhibits will follow in the next few days.