Auroras are especially large on Jupiter.
In pictures released
yesterday, the Hubble Space Telescope
imaged these unusual light displays in more detail than ever before.
Jupiter's auroras
are linked to its volcanic moon Io.
Io's volcanoes release particles,
some of which become ionized, trapped by Jupiter's
magnetic field, and rain down on the gas giant. The resulting
auroral displays may be thousands
of times brighter than any auroral display on Earth,
and involve unusual spots. The above pictures
show how the extended auroral emissions rotate with Jupiter, while
the auroral spots stay synchronized to Io as it circles Jupiter.
On This Day in Space History
On October 18, 1989, the Galileo spacecraft was launched toward Jupiter, where it would study the gas giant and its moons for 14 years.