Like Earth, Saturn features active and radiant auroras at its poles. To date, our impressions of these fantastic features have been fleeting and sporadic at best. But now, using several pairs of telescopic eyes, NASA has caught its best glimpse
Like Earth, Saturn features active and radiant auroras at its poles. To date, our impressions of these fantastic features have been fleeting and sporadic at best. But now, using several pairs of telescopic eyes, NASA has caught its best glimpse yet of these massive, swirling auroras.
Saturn's polar auroras become active when energetic electrons fall into the planet's atmosphere and collide with hydrogen molecules. Every once in a while, a blast of fast solar wind, comprised mainly of electrons and protons, generates glowing aurora.
To capture the northern auroras in ultraviolet wavelengths, NASA used the Hubble Space Telescope (which orbits around Earth). Its Cassini spacecraft (which is around Saturn), snapped close-up views in infrared, visible-light, and ultraviolet wavelengths. Cassini could also see northern and southern parts of Saturn that don't face Earth.
NASA tells us more:
"Saturn's auroras can be fickle — you may see fireworks, you may see nothing," said Jonathan Nichols of the University of Leicester in England, who led the work on the Hubble images. "In 2013, we were treated to a veritable smorgasbord of dancing auroras, from steadily shining rings to super-fast bursts of light shooting across the pole."
The Hubble and Cassini images were focused on April and May of 2013. Images from Cassini's ultraviolet imaging spectrometer (UVIS), obtained from an unusually close range of about six Saturn radii, provided a look at the changing patterns of faint emissions on scales of a few hundred miles (kilometers) and tied the changes in the auroras t