| The Saturn Season Begins: 2001-2002 Will Be Spectacular Photo and article by Jim Scala Arguably, the amateur's favorite showpiece, Saturn, will make excellent
observing during the 2001-2002 opposition that occurs on December 3rd.
At 20º 18' declination, where the air is clear, darkest, and above
the trees, the opposition will dominate the observing season. Even better,
the rings which are tilted 26º are almost at their widest of this
current 13.5 year ring cycle. Hence, this is a superb opportunity to study
Saturn's rings at their best, and to test your observing skills and understand
telescope limits. The above CCD image taken on August 8th at 0500 PDT (228-mm APO refractor)
illustrates a few of the possibilities available with amateur telescopes.
Saturn's disk at 17.52" and rings at 39.74" will increase to
20.6" and 46.6", respectively, by December 3rd. Most noticeable
on the rings is the dark Cassini division (almost empty space), which
was 0.62" wide, even though it seems larger. Test to see how small
a telescope allows you to see this division. Although Cassini's division
is small at 0.65", on average, it is an extended object (extended
dark space), making it possible for small telescopes to seemingly exceed
resolution limits. We all experience this when flying at about 30,000
feet and can see a road extending far into the distance well beyond our
eyes' resolving ability.
An interesting measure of Saturn's progress toward and then past opposition
is the slowly changing shadow of the planet on the rings, which are easily
seen just to the left in the image. This shadow will disappear at opposition
and then grow again on the opposite side. On September 10th at 0456, the Moon will occult Saturn in a dark sky.
Sky and Telescope and other publications have excellent detailed coverage
of this event. With the rings at 26º, this occultation will be the
most spectacular in many decades. |
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