A new phenomenon discovered in plasma could have major implications for understanding the turbulence associated with potentially dangerous space weather.
According to a recent paper published in The Astrophysical Journal Letters by an international team of researchers, a reversal in the direction of magnetic field rotation could play an important role in this cosmic turbulence.
Turbulence in space affects everything from space weather to the behavior of accretion disks, yet many of its underlying mechanisms remain poorly understood. By gaining a better understanding of the forces at work, scientists could eventually improve their ability to predict space weather events and protect vulnerable infrastructure.
Turbulence Explained
Turbulence is a physical phenomenon in which a fluid experiences sudden, chaotic changes in pressure, speed, and flow direction. On a small scale, it can be observed when a cup of liquid is stirred, or on a larger scale, when rough seas disturb a boat.
In space, however, turbulence occurs in a very different medium and is governed by additional physical processes. Rather than water, the medium is ionized plasma, whose behavior is strongly influenced by electromagnetic fields.
Unlike ordinary liquids, space plasma is often effectively collisionless, meaning interactions between particles are dominated by electromagnetic forces rather than frequent direct collisions. This has presented astrophysicists with longstanding questions about how turbulence develops in space and how its energy is distributed across different scales.
Now, an international research team spanning ten countries has identified a magnetic-field rotation reversal that could help explain an important aspect of space plasma turbulence.
Exploring Space Turbulence
The researchers analyzed magnetic-field and particle measurements collected by NASA’s Parker Solar Probe mission. Their analysis revealed that turbulent magnetic-field fluctuations reverse their sense of rotation at a particular wavelength, or scale. Intriguingly, this transition does not occur at a fixed wavelength. Instead, the farther the plasma is from the Sun, the longer the wavelength at which the reversal occurs.
Another important physical change accompanies the magnetic field reversal: the plasma dynamics go from large-scale, fluid-like behaviors to small-scale, particle-like ones.
At these two scales, plasma behaves very differently. The excitation of vortices and electromagnetic waves drives the turbulence at larger, fluid scales, creating random fluctuations. As the fields move away from the Sun, they tend to rotate counterclockwise at larger scales, yet at smaller particle scales, the fields rotate clockwise in turbulent plasma. Therefore, the scale at which behavior changes also reverses the flow of the plasma’s magnetic field rotation.
“We see a clear structure in the spectrum, even though the turbulence represents unstructured motions,” said first author Dr. Masatomi Iizawa of TU Braunschweig.
Moving Astrophysics Forward
The new findings provide important insight into the transition between fluid-like and particle-scale dynamics and how these processes influence turbulence in space plasma.
Understanding such turbulence is particularly relevant to space weather, which is driven by solar activity and can involve disturbances in the solar wind and Earth’s magnetosphere. These events can interfere with satellites, communications systems, and electrical infrastructure, making improved forecasting and mitigation an increasingly important priority.
“The results are of great significance for both plasma physics and astrophysics,” said co-author Nobumitsu Yokoi of the University of Tokyo.
Modern communications, navigation systems, and power infrastructure are all potentially vulnerable to severe space weather events. Satellites and other spacecraft face additional risks from energetic particles and electromagnetic disturbances, making a deeper understanding of the underlying physics especially valuable.
Although the newly identified phenomenon does not immediately translate into improved space weather forecasts, it offers researchers a clearer picture of how energy and magnetic fluctuations behave across different scales in turbulent plasma.
The paper, “Nonlocal Evolution of Magnetic Helicity across the Magnetohydrodynamic–Kinetic Interface,” appeared in The Astrophysical Journal Letters on October 9, 2026.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.