It isn’t only plasma from an external source like a star that can cause this-plasma from the magnetopause can also run into plasma from the level of the magnetosphere right below it. If the velocity shear overwhelms the magnetic tension, the boundary of the magnetopause is disturbed and waves start to form. This tension causes the plasma to have regional differences in velocity and direction this is known as velocity shear. At that location, there is magnetic tension at the interface between the planet’s magnetopause and the solar wind.

Jupiter is surrounded by a rotating disk of plasma that reaches its outer magnetosphere. How do these waves wash up in space? Plasma, which is swarming with charged particles, is always being scattered throughout the Solar System by the solar wind, and it inevitably ends up interacting with plasma in the outer atmospheres of planets. Now a team of researchers from the Southwest Research Institute (SWRI) and the University of Texas at San Antonio have analyzed Juno data and investigated the waves in detail. The probe has spent so much time hanging out by the magnetopause on Jupiter’s dawn side that it was able to observe more of them than any other spacecraft or telescope has. While these phenomena were previously known to happen on Earth and other planets and were suspected to occur on Jupiter, they had never been confirmed on the gas giant before Juno caught sight of them.

“The Kelvin-Helmholtz instability may be observed at the boundary that separates a planetary magnetic field (magnetosphere) from the stream of charged particles emitted by the Sun (solar wind) this boundary is known as the magnetopause,” the researchers said in a study recently published in Geophysical Research Letters. The difference in velocity between the magnetopause and solar wind creates a furiously swirling wave-a vortex. These waves are actually known as Kelvin-Helmholtz instabilities (KHIs), and they occur when plasma from the solar wind interacts with the magnetopause of a planet, the outer level of its magnetic field. NASA’s Juno spacecraft keeps coming across humongous plasma waves as it orbits Jupiter.

These plasma waves are much more intense than anything that crashes onto a beach. There are waves on Jupiter, but not exactly the kind surfers can ride. NASA/JPL-Caltech/SwRI/JunoCam reader comments 40 with

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