Saturn: Shadows of a Seasonal Sundial
Explanation:
Saturn's rings form one of the larger sundials known.
This
sundial, however, determines
only the
season of Saturn, not the time of day.
In 2009, during
Saturn's last equinox, Saturn's thin rings threw
almost no shadows onto Saturn, since the ring plane pointed
directly toward the Sun.
As Saturn continued in its orbit around the Sun, however, the ring shadows become
increasingly wider and cast further south.
These shadows are not easily visible from the Earth because from our vantage point
near the Sun, the rings
always
block the shadows.
The
above image was taken in August by the
robotic Cassini spacecraft currently orbiting Saturn.
The rings themselves appear as a vertical bar on the image right.
The Sun, far to the upper right, shines through the rings and casts captivatingly
complex shadows on south Saturn, on the image left.
Cassini has been
exploring Saturn,
its rings, and its moons since 2004, and is
expected to continue until at least the maximum elongation of Saturn's shadows
occurs in 2017.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
