Jovian Aurora
Credit:
J. Clarke (Univ. Michigan),
NASA
These two recently
released Hubble Space Telescope close-ups show the
Northern and Southern lights ...
on Jupiter.
Like aurora on Earth,
these Jovian
aurora are caused by charged particles
funneled into the atmosphere above the planet's North (right) and
South poles by
magnetic fields.
But Jupiter's magnetic field is extremely large and
ionized material expelled from
the volcanic moon Io
is trapped in it creating
light shows 1,000 times more intense than
Earth's auroral storms.
Charged particles released by Io are also funneled
along magnetic flux tubes which form a direct "bridge" to the Jovian
atmosphere.
The result is auroral hot spots - magnetic footprints 600 or more miles
across which race over
Jupiter's cloud tops.
A hot spot is visible in both images as a comet-like feature just
outside the polar auroral rings.
In these false color ultraviolet images, Jupiter's limb (edge)
appears dull brown while
the auroral displays
are shades of white and blue.