Scientists have created a three-meter "mini-sun" that reveals the secrets of a real star

Physicists at the University of Wisconsin-Madison have built a miniature analogue of the Sun called the Big Red Ball. It is designed to simulate the solar wind in various variations. But in the course of experiments, scientists managed to get an unplanned result - plasma loops-ejections.

The Big Red Ball is a hollow sphere with a diameter of 3 m, inside which there is a powerful controlled magnet, which serves to simulate the magnetic field of the Sun. Gaseous helium is pumped into the sphere, which is subjected to ionization to convert it into plasma. Further, it is ignited with the help of an electric pulse - this allows scientists to observe how a hot plasma behaves when the magnetic field changes.

The researchers began by simulating the Parker Spiral, a curved magnetic field that radiates from the Sun and permeates the Solar System. It is believed that near the Sun, the magnetic field is directed strictly away from the star. But at a certain distance - called the Alfvén radius - the magnetic field takes on a spiral shape. Big Red Ball clearly showed that the process develops in strict accordance with the hypothesis.

While manipulating the magnetic field, the team observed miniature plasma ejections in the zones of its weakening. The fast-moving plasma literally escaped the capture of the magnetic field and burst outward, separating from the bulk of the gas in the form of a characteristic "tongue". A similar phenomenon has been observed many times by astronomers, but it was obtained for the first time in laboratory conditions.