A laboratory model of the spiral structure of the Sun's magnetic field and plasma flows is reported in a paper published online this week in Nature Physics. This model can be used as an alternative method to study the phenomenon, as opposed to space missions such as NASA’s Parker Solar Probe mission.
The solar wind sweeps away the Sun’s magnetic field. As the Sun rotates, the magnetic field bends into a spiral structure known as the Parker spiral. The region where the magnetic field begins to stretch and twist is believed to be highly dynamic, but has been largely unexplored.
Ethan Peterson and colleagues recreated the Parker spiral in the laboratory by forcing a helium plasma to rotate in the Big Red Ball device (a plasma confinement vessel). Once the plasma spun fast enough, its magnetic field formed a spiral. The authors then used measurements of the magnetic structures and plasma flows taken from the probes in the Big Red Ball to understand the dynamics of this laboratory stellar wind.
The authors conclude that, although the Parker spiral is far more complex and expansive than its laboratory equivalent, this plasma model accurately reproduces the structure of the Sun’s magnetic field. They suggest that it could be used to further examine the origin and evolution of the solar wind.