Beneath their seemingly calm surface, stars harbour intense regions of turbulence.
Now researchers have created computer animations of these internal storms to reveal how stars get their spin.
They hope models such as this will help them understand the relationship between the spin of stars, their age and their huge magnetic fields.
They reveal the vicious turbulence within the plasma caused by the intense temperatures at the centre of the star, according to a report in Gizmodo.
The hottest stars may be almost 55,500°C (100,000°F) – far hotter than anything you have ever seen or felt here on Earth
‘Stars like the sun harbour vigorous regions of intense turbulence below their seemingly calm surfaces,’ writes the National Science Foundation, which released the animations.
‘The turbulent motions are known as convection and they arise from the searing heat produced deep in the stellar core.’
As well as having turbulent cores, stars also spin, and the younger they are the faster they spin. These spinning and churning motions convert kinetic energy into magnetic energy.
In January, US scientists were able, for the first time, to measure the spin speed of stars that are more than one billion years old.
They said their findings could help plot how old the various stars in our universe are, and also help tell scientists where in space alien life is most likely to be found.
Their method, accurate to around 10 per cent of the star’s real age, works on ‘cool stars’, which are suns that are about the same size as our own, or smaller.
These cool stars last for a long time and host most of majority of Earth-like found by the Kepler probe.
Knowing a star’s age is particularly relevant to the search for signs of alien life outside our solar system.
A star’s spin rate depends on its age because it slows down steadily with time, like a top spinning on a table.
A star’s spin also depends on its mass; astronomers have found that larger, heavier stars tend to spin faster than smaller, lighter ones.
This new work shows that there is a close mathematical relationship between mass, spin, and age so that by measuring the first two, scientists can calculate the third.
‘We have found that the relationship between mass, rotation rate and age is now defined well enough by observations that we can obtain the ages of individual stars to within 10 per cent,’ explains co-author Sydney Barnes of the Leibniz Institute for Astrophysics in Germany.