Don’t get spooked by Saturn’s ghostly spokes! Today we feature a nearly two-hour timelapse of Saturn
and its rings looping forwards and backwards. If you look closely, a ghoulish shadow appears and
disappears as
Saturn’s B ring
rotates. Decades of observation with
Voyager 2,
Cassini,
and
Hubble
show the appearance of Saturn’s spokes varies with
the planet’s seasons.
Like Earth, Saturn’s
spin axis
is tilted compared to the plane of its orbit around the Sun. During Saturn’s
equinox,
the rings are
less tilted
toward the Sun and they receive sunlight at a shallower angle. Saturn’s spokes may be electrically
charged dust and ice temporarily levitated above the rings by
electromagnetic
forces. It is still uncertain, but the ring plasma and charge environment may be influenced by changing
ultraviolet
illumination, meteoroid impacts, or indirect effects from interactions between the
solar wind
and the planet’s magnetic field.