A study of Jupiter’s atmosphere has revealed aurorae that outshine those on Earth by a factor of several hundred times.
Aurora are caused by interactions with solar wind and a planet’s magnetic field. When charged particles from the sun disturb magnetic fields the particles interact with atoms and molecules in a planet’s pole to produce amazing light shows.
When this happens on Earth it’s known as the Aurora Borealis, or Australis – and it’s quite a sight. Earth is relatively close to the Sun which allows for aurorae to form around it’s magnetic field, but even though Jupiter is five times the distance it can produce the same effect – thanks in part to a magnetic field that puts the Earth’s to shame. Because of this large field, Jupiter can produce aurorae more frequently than Earth.
“There’s a constant power struggle between the solar wind and Jupiter’s magnetosphere,” says William Dunn, of the University College London. “We want to understand this interaction and what effect it has on the planet. By studying how the aurora changes, we can discover more about the region of space controlled by Jupiter’s magnetic field, and if or how this is influenced by the Sun. Understanding this relationship is important for the countless magnetic objects across the galaxy, including exoplanets, brown dwarfs and neutron stars.”
Dunn describes the observations of a coronal mass ejection (or CME) that reached Jupiter in 2011 in the journal of Space Physics. In this he speaks on the Juno’s spacecraft mission, which will arrive at Jupiter in July. One of Juno’s goals will be to study the magnetosphere of Jupiter for this very phenomena (We’re hoping we’ll get some amazing pictures).
The observations also show that X-Ray emissions are largely accelerated by Jupiter’s magnetic field. These aurorae are so powerful that they produce X-Ray emissions visible to Chandra’s X-Ray telescope here on Earth.