October 8, 2009 NASA’s Spitzer Space Telescope has discovered a
new ring around Saturn. This ring is very different from those
previously known. In some ways, this ring resembles the
“accretionary disk” found around some stars more than it
resembles the thin, orderly rings that Saturn is famous for. The
new ring is much larger than any of the planet’s other rings and
is tilted about 27 degrees off the main plane of rings. It
starts about six million kilometers out from the planet, and is
about 12 million kilometers wide. The moon Phoebe orbits just
within this ring and is tentatively thought to be responsible
for the ring’s existence. It would appear that as Phoebe circles
around Saturn, it occasionally collides with comets, which are
obliterated, with the debris from the collision contributing to
the ring. This ring is different from the other rings not only
in its angle, but also in its thickness. The better known
Saturnian rings are very thin (about 10 meters thick), but this
mega-ring measures about 2.5 m