Planets: How the Polar Lights Form on Jupiter

The northern lights are not a feature of the Earth. Jupiter, the largest planet in our solar system, also has aurorae, which were discovered in 1979 by NASA’s Voyager 1 space probe. Since then, it has not been clear how exactly Jupiter’s northern lights are generated. Are the processes there at least similar to Earth’s magnetosphere? Or is there something completely different at work? A research team led by Zhonghua Yao of the Chinese Academy of Sciences has now In the journal » Science Advances « Presented at least a partial solution.

To do this, the researchers combined on-site measurements with observations from the ESA XMM-Newton Space Telescope, which targets space in the X-ray range of the electromagnetic spectrum. Jupiter’s northern lights may be spectacular, after all, as it has the strongest magnetic field of all the planets in our solar system. However, this is why, unlike their earthly counterparts, very few of these very bright polar lights can be seen in the visible region. They are so energetic that they mainly emit light in the UV and X-ray ranges in the polar regions of Jupiter.

While the space telescope XXM-Newton can observe Jupiter auroras from an orbit around Earth, the NASA space probe Juno is on site at Jupiter. Juno has been researching the gas planet since 2016 and may also study the magnetosphere. On July 16 and 17, 2017, Zhonghua Yao’s team was able to observe aurora activity at Jupiter’s north pole with the help of XXM-Newton, while the Juno space probe measured the gas giant’s magnetic field during the same period.

Juno and XXM-Newton provide clues about origin of Jupiter northern lights

On Earth, to put it simply, the interaction between the terrestrial magnetic field and charged particles such as electrons and protons is responsible for auroras. Solar winds, the charged particles that flow through our central star, play a major role in this. They send those charged particles on their journey through the solar system for the first time. With Jupiter, which is further away, solar winds may also play a role. In addition, the Jupiter moon Io serves as a supplier of charged particles: Io is volcanically active and produces sulfur dioxide gas in the process. Jupiter’s magnetosphere is gradually enriched with sulfur and oxygen ions.