Curated by RSF Research Staff
Jupiter’s Insane Auroras are Powered by an Energy Source Nobody can Explain
The dynamic dance between the Earth’s magnetic field and the solar wind – the aurora - is said to be one of the most magnificent sites we can observe here on Earth.
The physics of the processes taking place and the interaction between the solar wind and the Earth’s magnetosphere is well studied and understood, in that it is the result of charged particles being accelerated towards and interacting with the neutral atmosphere of the Earth.
The charged particles, originating from the Sun, are accelerated towards the Earth’s magnetic poles. It is here at the magnetic poles - where the magnetic field is weakest - that the charged particles enter and subsequently interact with the neutral atmosphere. The molecules and atoms of the Earth’s upper atmosphere are ionized and/or excited by the charged particles causing them to emit light, as they relax into their ground state, which is the glow that we see and call the aurora.
The most intense auroral emissions from Earths polar regions are thought to be due to the steady stream of charged particles that are accelerated downwards towards the polar regions of the Earth’s atmosphere. In contrast, the Earths less intense auroras are generally caused by either the scattering of electrons that are magnetically trapped in the inner radiation belt known as the Van Allen belts or by the turbulent or stochastic downward acceleration of electrons.
Jupiter’s aurora is known to have a significantly larger power density than the Earths aurora so it was assumed that a similar process, to that responsible for the intense auroral emissions from Earths polar regions, would also be responsible for generating the auroral displays of Jupiter. However, this does not seem to be the case, and instead the downward acceleration of charged particles was found to be more significant from turbulent or stochastic processes.
"At Jupiter, the brightest auroras are caused by some kind of turbulent acceleration process that we do not understand very well," explains lead researcher Barry Mauk from Johns Hopkins University.
These findings open up a whole new understanding of the origin and dynamics of the planetary magnetic fields and its interaction with the charged particles of the surrounding plasma – either originating from the Sun and/or from the surrounding regions.