Jupiter's polar vortices: Magnetic mysteries unraveled

At the poles of Jupiter, the largest planet in the Solar System, vortices rage for months and are as large as our planet. As scientists report in the journal Nature Astronomy, these phenomena are caused by magnetic tornadoes reaching deep into Jupiter's atmosphere, lifting hazy gases upwards.

While long-lasting vortices are not uncommon on Jupiter— the most famous one, the Great Red Spot, was observed as early as 1664 by Robert Hooke—their presence at the poles was unexpected. In the 1990s, the Hubble telescope captured dark oval shapes at both poles of the planet. In 2000, the Cassini probe confirmed the existence of this phenomenon at Jupiter's northern pole.

To unravel this mystery, a team led by Troy Tsubota from the University of California, Berkeley, analyzed images from the OPAL project (Outer Planets Atmosphere Legacy). Over 28 years of observation, eight dark ovals were identified at the southern pole and two at the northern pole, appearing within a month and disappearing after a few weeks.

Researchers determined that these vortices are caused by Jupiter's strong magnetic field, which is 20,000 times stronger than Earth's. Charged particles from the volcanoes on the moon Io and a ring of particles around the planet interact with the magnetic field at the poles, forming magnetic vortices. These vortices pull dense, hazy gases from deep layers of the atmosphere, which absorb ultraviolet radiation, making these areas appear darker.

The haze in the dark ovals is 50 times thicker than the typical concentration, explained team member Xi Zhang from the University of California, Santa Cruz, as quoted by the portal welt.de.

Therefore, the vortices at Jupiter’s poles are the result of volcanism on Io, caused by the planet's strong gravitational interaction. These discoveries are significant for understanding Jupiter and aiding research on large gas planets orbiting other stars.