April 7, 2021
NASA’s Juno spacecraft – whose mission in orbit around Jupiter was recently extended to 2025 – has been used to discover a rapidly expanding auroral ring at the very fringes of the Jovian magnetosphere.
NASA said: “In this Hubble telescope picture, a curtain of glowing gas is wrapped around Jupiter’s north pole like a lasso. This curtain of light, called an aurora, is produced when high-energy electrons race along the planet’s magnetic field and into the upper atmosphere where they excite atmospheric gases, causing them to glow. The aurora resembles the same phenomenon that crowns Earth’s polar regions.” Image via NASA/ ESA/ John Clarke (University of Michigan)/ SwRI.