News & Analysis
/
Article

A turbulent journey toward understanding space plasma dynamics

SEP 01, 2023
Discontinuities caused by supersonic shocks provide insight into the nature of energy dissipation in turbulent plasmas.
A turbulent journey toward understanding space plasma dynamics internal name

A turbulent journey toward understanding space plasma dynamics lead image

Charged particles from the sun arrive at Earth too fast to dodge it. As a result, they collide with the planet’s magnetosphere, triggering a shock wave called the bow shock and sending ripples through the plasma to the magnetic and electric fields that permeate space. This disruption could help explain how turbulence works in space.

Turbulence is the primary method by which energy transfers from larger scales to smaller ones. Often, energy transfer can be explained through particle collisions, but these are rare in the vacuum of space. The physics of plasma could lend needed insight.

Plank and Gingell investigated how the bow shock disrupts turbulence in plasma. They used in-situ measurements of the magnetic spectrum, intermittency of ripples in the magnetic field, and the size of large structures from NASA’s Magnetospheric Multiscale mission to form a picture of turbulence.

“There are measurable differences in turbulence when looking at areas of space before the bow shock and after, indicating that a shock discontinuity can affect the turbulence,” said author James Plank.

The turbulence rebound time is on the order of seconds to minutes, depending on the size of the discontinuity and the angle at which the magnetic field intersects with the shock.

“Our results show that turbulence appears to be very difficult to get rid of in space plasmas,” said Plank. “Collisions with planetary bow shocks are one of the most dramatic things that can happen to a plasma in space, so to find that fully developed turbulence recovers so rapidly indicates that it is not a fragile state that occurs only in precisely balanced situations, but rather a mostly fundamental part of space plasma behavior.”

Source: “Intermittency at Earth’s bow shock: Measures of turbulence in quasi-parallel and quasi-perpendicular shocks,” by J. Plank and I. L. Gingell, Physics of Plasmas (2023). The article can be accessed at https://doi.org/10.1063/5.0160439 .

Related Topics
More Science
APS
/
Article
APS
/
Article
/
Article
Quantifying artistic properties with scaling analysis demands grid independence and careful analysis.
/
Article
Magnetic fields can be optimized to enhance the yield of extreme ultraviolet radiation from laser-driven plasmas.
/
Article
Ptychography can capture signals from light elements in a dose-effective manner in 3D, providing a more complete understanding of upconverting core-shell nanoparticles than conventional methods.
/
Article
Electrical stimulation can artificially recreate visual stimuli, but developing the signals requires a mechanism to monitor them.