What Do You Need To Observe Saturn?
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At left is an example of the impression of Saturn you might get on a good
night through a small telescope. The image would actually be smaller, but you
could perceive about this level of detail on the great ringed planet.
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To get at least enough resolving power to clearly perceive Saturn's rings
you will need at least a 2 inch telescope. Of course, the bigger the
telescope, the more detail you will likely see.
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A great choice for a telescope for Saturn viewing is a long focus refractor. I observe
planets routinely through a quality 60mm refractor of long focus, and get very
enjoyable views. Superb views of Saturn can be obtained with a 4 inch
refractor, but nice views through any quality refractor telescope are routine.
I've even obtained good views of Saturn, Jupiter, and Mars with the quality
50mm refractor shown at left.
Refractors perform well because they tend to cool down to ambient
temperature quicker that other telescope types and give steadier views. They
also give the highest contrast views for a telescope of any given aperture.
You can see Saturn and possibly 4 or 5 if it's moons at low power,
between 50x and 100x. To see the rings in some detail, you'll need to
move to 100x or better.
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Another good choice for observing Saturn is a Maksutov telescope. Even a
90mm (3.5 inch) version will easily show the Saturn's rings and likely the
Cassini division, the dark gab in the rings.
Maksutov telescopes are renowned for their crisp images that are free of
chromatic aberration. They also have high focal ratios and thus long effective
focal lengths, making them ideal for planetary observing. While they can't
quite match up to the contrast of an equal diameter refractor, the Maksutov
will none-the-less deliver very pleasing views of Saturn.
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Schmidt Cassegrain (SCT) telescopes can also be used successfully,
especially on Saturn. The SCT has a large secondary with respect to its
objective, and this tends to reduce the contrast of the image. But Saturn with
its rings presents a fairly high contrast target, so the loss of contrast is
tolerable.
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One of my favorite telescope for planetary work is the Long Focus Newtonian.
Such telescopes can be constructed or purchased cheaply compared to other
similar sized instruments. The long focus Newtonian can use a smaller diagonal
to reduce the loss of contrast. They also are less sensitive to alignment
errors, and offer flat, coma free fields of view. The 4.25 inch f/10 Newtonian
is a commonly available telescope, and makes a great planetary instrument for
the small budget.
Pictured at left is my 6 inch f/10 Stargazer Steve Newtonian. It is designed
to give near refractor performance on planetary objects for a fraction of the
cost of a similar sized refractor.
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While the telescopes listed on this web page are my preferences for getting
the best planetary images, I strongly suggest that you use whatever telescope
you have. Any decent telescope will let you see the beautiful ring system of
Saturn.
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If you don't have a telescope, or need to find eyepieces, filters, or some accessory to augment your planetary viewing, use this tailored search to shop
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What Can You See On Saturn?
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At left you see an illustration of the main features of Saturn that are
within reach of the typical amateur astronomer telescope.
The obvious thing is of course the rings. Most telescopes of 50mm or
better will show the rings and likely the ring gap -- the area between
the rings and the planet itself. Depending upon the relationship between
Earth, Saturn, and the Sun, you may see the planet's shadow cast on
the rings as they pass behind the planet.
Moving up in size to 60mm or 70mm, you are likely to be able to see
the small dark gap in the rings known as the Cassini Division.
There is yet another, much smaller gap near the outer edge of the rings known
as the Encke Gap, but most small telescopes will not likely see this
feature.
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A telescope of perhaps 6 inches or so may show the illusive inner, darker
and somewhat translucent ring known as the Crepe Ring.. Depending
upon where Saturn is in it's cyclic pattern around the sun, the rings
may appear tipped either up or down.
On the planet itself is a light colored band around the equator of
Saturn. You may also notice darkening at the poles of Saturn.
Note that the sizes of telescopes suggested for observing these features is
approximate. Experienced observers can often see details through small
telescopes that are only obvious to others in larger telescopes.
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As Saturn goes along its decades long journey around the sun, the
inclination of its rings changes. At left is an example of how Saturn may look
when the rings are viewed more nearly edge on.
In fact, about every 14 to 15 years, Saturn's rings are viewed
precisely edge on, and become invisible to the Earthly observer. The
most recent one of these ring disappearing acts occurred in early September
of 2009.
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The View Of Saturn Tonight
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This image of the current inclination of Saturn's rings was obtained with
the xephem
program, and is called the xephem Saturn view. It shows tonight's
approximate view of Saturn, and is particularly useful in predicting what the
tilt will be in Saturn's rings.
Any roman numerals in this image refer to Saturn's moons that might
be visible in this narrow field of view depiction.
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This is a wider field of view depiction of the xephem Saturn view
illustration. It is handy for finding out which moons of Saturn will be
visible tonight, and where they will be located.
The orientation of this view is that seen through a telescope with a star
diagonal attachment. It's right side up but reversed from left to right, as in
a typical refractor or Cassegrain telescope.
The labeling for Saturn's moons is shown in the following table.
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| Label | Name | Magnitude |
| I | Mimas | 13 |
| II | Enceladus | 11.8 |
| III | Tethys | 10.3 |
| IV | Dione | 10.2 |
| V | Rhea | 9.8 |
| VI | Titan | 8.4 |
Some Final Suggestions
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There are things you can do to improve your Saturn viewing. Let your
telescope cool down to ambient temperature before expecting it to deliver
steady images. The time this takes is longer for bigger telescopes, and
generally longer for reflector type telescopes.
Don't observe over the top of nearby buildings. The heat rising from the
buildings will cause significant image instability. If possible, observe when
the planet is highest in the sky, rather than low to the horizon.
Try using a color filter on your eyepiece. Yellow is a common filter
used to enhance the contrast of the Saturn features. I generally use an
apodizing screen on my 6 inch f/5. That apodizing screen helps reduce
some of the light scattered by the secondary. That has the effect of slightly
enhancing contrast.
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