MADRID, 19 (EUROPA PRESS)
Researchers at the University of Minnesota Twin Cities have made a groundbreaking discovery by observing and analyzing the first new type of plasma wave in Jupiter's aurora.
According to the authors, this research helps us understand "extraterrestrial auroras" on other planets, which in turn teaches us more about how Earth's magnetic field protects us from harmful solar radiation. The findings are published in Physical Review Letters.
The observation is based on data from NASA's Juno spacecraft, which flew in low orbit above Jupiter's north pole, where the team was able to apply its data analysis expertise to study data from Jupiter's northern polar regions for the first time.
"The James Webb Space Telescope has provided us with some infrared images of the aurora, but Juno is the first spacecraft to orbit Jupiter in polar orbit," said Ali Sulaiman, an assistant professor in the University of Minnesota's School of Physics and Astronomy.
The space surrounding magnetized planets like Jupiter is filled with plasma, a superheated state of matter where atoms break down into electrons and ions. These particles accelerate into the planet's atmosphere, causing the gases to glow like an aurora. On Earth, this is visible as the familiar green and blue lights. However, Jupiter's aurora is usually invisible to the naked eye and can only be observed with ultraviolet and infrared instruments.
The team's analysis revealed that, due to the extremely low density of Jupiter's polar plasma, combined with its strong magnetic field, the plasma waves have a very low frequency, unlike anything previously observed around Earth.
"While plasma can behave like a fluid, it is also influenced by its own magnetic fields and external fields," said Robert Lysak, a professor in the University of Minnesota's School of Physics and Astronomy and an expert in plasma dynamics.
The study also sheds light on how Jupiter's complex magnetic field allows particles to flood the ice cap, unlike on Earth, where the aurora forms a doughnut-like pattern of auroral activity around the ice cap. Researchers hope to gather more data as Juno continues its mission to support research into this new phenomenon.
In addition to Lysak and Sulaiman, the research team included Sadie Elliott, a researcher in the School of Physics and Astronomy, along with researchers from the University of Iowa and the Southwest Research Institute.
