Explanation:
How would Saturn look if its ring plane pointed right at the Sun?
Before last month, nobody knew.
Every 15 years, as seen from Earth,
Saturn's rings
point toward the Earth and
appear to disappear.
The disappearing rings are no longer a mystery -- Saturn's rings are known to be
so thin and the
Earth is so near the Sun
that when the rings point toward the Sun, they also point
nearly edge-on at the Earth.
Fortunately, in this
third millennium, humanity is advanced enough to have a spacecraft that can see the rings
during equinox
from the side.
Last month, that Saturn-orbiting spacecraft,
Cassini,
was able to snap a series of unprecedented pictures of
Saturn's rings during equinox.
A digital composite of 75 such images is
shown above.
The rings appear unusually dark, and a very thin ring shadow line can be made out on Saturn's cloud-tops.
Objects sticking out of the ring plane are
brightly illuminated and cast
long shadows.
Inspection of these images may help
humanity understand the specific
sizes of Saturn's ring particles and the
general dynamics
of orbital motion.
digg_url = 'http://apod.nasa.gov/apod/ap090930.html'; digg_skin = 'compact';
