
Auroras On Jupiter
Yesterday, NASA released the first James Webb Space Telescope (JWST) images of auroras on Jupiter. The red rings of light were big enough to swallow Earth. Jupiter’s auroras are unlike any others in the solar system.
For one thing, solar activity is not required. The giant planet makes its own Northern and Southern Lights. It does this by spinning–like crazy. Jupiter turns on it axis once every 10 hours, dragging its planetary magnetic field around with it.
As every freshman physics student knows, spinning a magnet is a great way to generate a few volts. Jupiter’s spin produces 10 million volts around its poles. Jupiter’s poles are crackling with electricity, and this sets the stage for non-stop auroras.
Volcanoes on Io spew ions such as O+ and S+ into Jupiter’s magnetosphere. Polar electric fields grab these ions and slam them into the planet’s atmosphere, producing volcano-powered lights. (Solar wind and CMEs can also help.)
Two distinct auroras coexist over the poles of Jupiter: Ultraviolet auroras created by atmospheric hydrogen in its molecular form (H2) and infrared auroras created by the hydrogen ion H3+. JWST saw the infrared auroras. (Credits NASA)