The Ultimate Guide to Observing Saturn
November 11, 2020
There is no object in our Solar System more breathtaking than the sixth planet from the Sun, Saturn. Saturn was named after the Roman god Saturnus, known in Greek mythology as Cronus, the god of agriculture and abundance. The planet’s opulent rings certainly evoke this image of wealth.
Saturn has captured the admiration of telescope viewers for hundreds of years. Its magnificent rings can singlehandedly claim credit for inspiring countless people around the world to discover the hobby of astronomy. As any amateur observer can tell you, viewing Saturn’s rings through a telescope for the first time is unforgettable. And once you’ve seen it, the planet is sure to remain a favorite target for years to come.
Finding Saturn in Fall/Winter 2020
The second largest planet in the Solar System, Saturn is only slightly smaller than its neighbor and fellow gas giant, Jupiter. Saturn is the most distant planet visible to the naked eye. You can currently find it in the constellation Sagittarius, just to the east of Jupiter and currently about 6 degrees away and closing. Although Saturn is now several months past its opposition when it was closest to Earth, it continues to be a prominent object and well placed in the southern night sky.
However, Saturn is quickly heading westward. In the coming weeks, it will continue to move closer to Jupiter for their historic winter solstice “Great Conjunction” on December 21.
So, let us become better acquainted with Saturn, the true “Lord of the Rings.” We will share some interesting facts about Saturn, give our recommendations on equipment, point out the planet’s must-see features, provide some helpful observing tips, and more.
15 Key Saturn Facts
- Although Galileo Galilei was the first person to observe Saturn through a telescope, his tiny refractor was not powerful enough to discern its rings for what they were. Instead, he noted that the gas giant had "lobes." Dutch astronomer Christiaan Huygens was the first to propose that Saturn was surrounded by a ring in 1655. He’s credited with discovering Saturn’s rings.
- It takes 29.5 Earth years for Saturn to orbit around the Sun. On Saturn, you would be nearly 30 years old celebrating your first birthday!
- It would take 9.5 Earths side by side to span Saturn’s equatorial diameter, and 21 Earths side by side to span its massive rings.
- When the Earth and Saturn are at their closest, they lie approximately 746 million miles apart. When they are on opposite sides of the Sun, they can be over a billion miles apart.
- If Saturn were hollow, more than 700 Earths could easily fit inside of it.
- With the discovery of 20 additional moons orbiting around Saturn, its moon tally now stands at 82—three more than Jupiter. It’s now recognized as having the most known moons of any planet in the Solar System.
- One of Saturn’s smallest moons, Enceladus, is covered in ice and appears to have an ocean hidden below its frozen surface. The Cassini spacecraft has observed water plumes jetting out into space, which may reveal a possible habitable environment under its surface.
- Titan is Saturn’s largest moon and is the second largest moon in the Solar System. It has a thick yellow-orange-like atmosphere made up of methane and nitrogen, and its surface was found to contain many liquid methane lakes. Only one space probe, Huygens, descended to its surface and briefly transmitted data back to the Cassini orbiter until its batteries failed.
- Saturn is the least dense planet in the Solar System. If there was a body of water large enough to hold it, Saturn would float.
- Like Jupiter, Saturn is made up of hydrogen and helium with no actual land mass. Its top cloud layers are made up of ammonia ice. Below, it is made up of mostly water ice with bands of intermixed ammonium hydrosulfide ice.
- Saturn’s largest storm is twice as large as Earth. It is located at the planet’s north pole and is shaped as a near-perfect hexagon. It was first discovered by Voyager and later mapped by Cassini. Australian husband and wife team, Darryl Milika and Patricia Nicholas, are credited for being the first amateur astronomers to image the hexagon in 2013 using a Celestron C14.
- Saturn is the flattest planet in the Solar System due to its low density and fast rotation speed. It takes approximately 10 and a half hours to make a complete rotation on its axis.
- Although other planets do have rings, Saturn has the most complex ring system in the Solar System. The rings are made up of billions of particles of dust, chunks of ice, and rocky remnants of comets, asteroids and shattered moons. The rings extend out more than 175,000 miles from the planet but are quite thin: only about 100 yards in thickness. To understand the thinness of the rings, imagine an 8.5” x 11” sheet of paper. If the 11” long axis of the sheet represents the span of the rings from one side to the other, the thickness of the rings would only be 1/100th the thickness of the paper! (And that is using the widest thickness of the rings that we have measured.)
- The rings are divided into seven groups (four main and three fainter). Outwards from Saturn, the rings are: D, C, B, A, F, G and E.
- Four spacecraft have visited Saturn. Pioneer 11, Voyager 1, and Voyager 2 flew by the planet. Cassini orbited Saturn 294 times from 2004 to 2017, gathering a wealth of information before ending its mission in a fiery (but planned) “death dive.”
The Best Equipment for Viewing Saturn
Telescopes: Any small telescope with an aperture of at least 50mm and modest power (25x) will be enough to reveal Saturn’s rings and its brightest moon, Titan. Maksutov-Cassegrain and Schmidt-Cassegrain telescopes (ranging from 4” to 14” in aperture), are our best picks for observing Saturn due to their increased light gathering ability, longer focal lengths, and ability to accommodate higher magnifications (150x or more). A larger telescope will reveal detail in Saturn’s atmosphere and in its rings when seeing conditions are calm. Consider using a large telescope to be able to clearly observe prominent features. Just remember that the larger a telescope’s mirror or lens is, the more light it will collect and the better the resolution will be. However, it will also add more to the cost and weight of the telescope, so carefully consider these factors when choosing your ideal telescope.
Filters: Color filters are a great way to enhance subtle features in Saturn’s atmosphere for a more enjoyable observing experience. Filters can individually thread onto the end of eyepiece barrels or be stacked together to enjoy the benefits multiple filters at once. (Please note that when you stack filters, light is diminished. We only recommend doing so with telescopes of at least 8” aperture.) Here are the most popular filters for enhancing details on Saturn:
#12 Deep Yellow Filter 74% Transmission - Penetrates and darkens atmospheric currents containing low-hue blue tones. Enhance orange and red features of the belts and zones.
#21 Orange Filter 46% Transmission - Improves structure of the cloud bands and highlights blue polar regions.
#25 Red Filter 14% Transmission – Aids in observation of bluer clouds.
#58 Green 24% Transmission - Enhances white features in the Saturnian atmosphere.
#80A Blue Filter 30% Transmission - Enhances low-contrast features found between the belts and zones.
Variable Polarizing Filter - Reduces light transmission and is great for reducing glare.
Color filters are available in the following Celestron products:
- PowerSeeker Accessory Kit - 1.25” #94306
- AstroMaster Accessory Kit - 1.25" #94307
- Observer's Accessory Kit - 1.25" #94308
- Lunar and Planetary Filter Set - 1.25" #94119-10
- Eyepiece and Filter Kit - 1.25” #94303
- Eyepiece and Filter Kit - 2” #94305
Cameras and Phone Adapters: Now that you have observed Saturn visually, take your experience to the next level by capturing detailed images of the ringed planet with your smartphone, DSLR, or a planetary imaging camera. Smartphones’ built-in cameras are continuously improving. You can hold your phone up directly to the telescope’s eyepiece to take advantage of the telescope’s image scale with higher magnification to capture the planet and its magnificent rings. You have the option of using the smartphone’s digital zoom feature to increase Saturn’s size to your liking. It can be tricky to properly center your target, but by using a smartphone adapter like the Basic Phone Adapter #81035 or the NexYZ 3-Axis Universal Smartphone Adapter #81055, centering Saturn will be quick and easy.
DSLR cameras are another popular tool you can use to capture Saturn. You will need a T-Adapter (there are different models available for your telescope), and a camera-specific T-Ring (i.e. Canon, Nikon, etc.). The T-Ring attaches to your camera’s bayonet. Then, the T-Adapter threads onto the T-Ring. Depending on the T-Adapter you are using, it will either slide into the eyepiece drawtube, or screw directly onto the telescope’s rear cell.
Planetary imaging cameras are also a great way to capture high-resolution images with tremendous detail—and getting started is easier than you might think! The camera takes the place of your telescope’s eyepiece and connects via USB to your computer or laptop. Software analyzes each frame of the live video capture and throws away the images that are blurry due to poor atmospheric turbulence. It then stacks and perfectly aligns the clearest video frames to create a bright, detailed, colorful image. Celestron’s planetary imaging cameras include:
- NexImage 5 #93711
- NexImage 10 #93708
- Skyris 132C #95508
What to Look for while Observing Saturn
Rings: The rings are, by far, Saturn’s most popular feature. A smaller aperture telescope will show the rings as a tiny cream-colored oval circling the planet. With a larger aperture telescope in steady seeing, the rings will begin to show some of their complex divisions. Look for the main outer A ring and middle B ring separated by the black gap known as the Cassini Division. If you are up for a challenge and have access to an 11” or larger telescope under extremely steady seeing, try to hunt for the elusive faint Encke division gap near the outer A ring’s edge. Take notice of the ring’s tilt over time. In 2017, the rings were opened at their widest (27 degrees) as seen from Earth. Since then, they have slowly decreased in angle. By 2025, the rings will appear edge-on and—because they are so thin—will virtually disappear, leaving Saturn’s appearance as a lonely orb. Gradually, the rings will begin to reopen until they are at maximum tilt again in 2032.
Seeliger Effect: For a few nights around the time of Opposition (when the planet is fully illuminated by the Sun), you may see Saturn’s rings shining a bit brighter. It’s during this time that Saturn’s shadow hides behind the planet, placing more of its ring surface in view. Because the rings are made of small particles, their shadows also disappear, while sunlight is reflected to our line of sight. All these factors contribute to Saturn’s rings appearing temporarily brighter than normal.
Shadows: There is a fascinating interplay of shadow and light to observe on Saturn. At times, the rings cast interesting shadows onto the planet. Other times, the planet casts its shadow onto the rings. Observe over many nights to see these changes.
Moons: Approximately 6 of Saturn’s 82 moons can be observed through amateur telescopes. Its largest moon, Titan, shines about 9th magnitude and is easily visible. Try to correctly identify Titan, Rhea, Dione, Tethys, Enceladus and Mimas during your observing session.
Belts and Zones: Look for dark belts and zones on Saturn’s face. They strongly flow in opposite directions around the entire planet. They are much less pronounced than Jupiter’s belts and zones, and smaller storms can be found within these regions. Use color filters to help bring out detail.
Conjunctions: Planetary alignments, or conjunctions, occur when two or more planets appear very close together in the night sky. They are often spectacular to see—especially if they involve the largest or brightest planets. Such a “Great Conjunction” will take place on the evening of the winter solstice, December 21, 2020, when Saturn and Jupiter will be separated by only 0.1 degree–meaning both planets will be visible in the same telescopic field of view! The two planets will be low in the southwestern sky at dusk. Do not miss this historic super conjunction!
Helpful Observing Hints
There’s still time to observe Saturn! Saturn is currently well placed in the southern sky and will be visible through the end of the year. Saturn is a few degrees away from Jupiter, and the two will gradually move closer together in the coming months.
Steady seeing conditions are critical when imaging or observing Saturn. Avoid nights of bad seeing when our atmosphere is turbulent, and Saturn appears like a shimmering blob on your laptop screen or in a telescope eyepiece. Start with low magnification and work your way up if the views remain steady. During a night of good seeing, you will be amazed how sharp and detailed Saturn will appear—even the Cassini Division will be obvious.
Cool your telescope down! Make sure you bring your telescope outside about an hour or so before you plan to observe to cool it to ambient temperature. It is important for the telescope to reach thermal equilibrium with the outside air temperature to avoid distorted views. Telescopes with large mirrors and lenses may take longer to properly cool down for the best views.
Collimate, collimate, collimate! If you own a Newtonian or Schmidt-Cassegrain telescope, make sure your telescope’s optics are collimated. It can make a difference when it comes to discerning fine planetary detail. If the optics are slightly out of alignment, you may be cheating yourself out of seeing the clearest and sharpest details on Saturn. Make it a habit to check collimation and adjust as needed once your telescope is cooled down. Most refractor telescopes generally do not need to be collimated.
Observe Saturn in twilight. Why wait until complete darkness to begin observing Saturn? Saturn is bright enough to be seen in a telescope around dusk. With Celestron’s Solar System Align, you can align your computerized telescope on the Moon (if visible) or Sun (with a safe solar filter in place) and then command your telescope to slew to Saturn. Having an optical finderscope is very helpful to finding Saturn in the deepening twilight sky and fine tuning your alignment. Give it a try! (Remember to always use caution and keep your telescope pointed far away from the Sun when observing during the day.)
Use a Stereo Binocular Viewer. Saturn displays a noticeable 3-D appearance caused by darkened edges of the planet’s disk. A stereo binocular viewer attached to a mid- to large-aperture Schmidt-Cassegrain or Maksutov-Cassegrain telescope will really enhance the 3-D effect. It’s as if you can reach out and touch the planet! You will need to use two matching eyepieces of the same focal length, which can be costly, but you will be rewarded with an amazing, realistic view full of detail and contrast that makes it a great investment.
Saturn is one of the most exciting planets to view through a telescope. Its rings always steal the show and never fail to be an alluring target for backyard astronomers. Saturn’s beauty is so overwhelming that it is not uncommon for first time observers to ask, “Are you holding up a photo of Saturn in front of the telescope?”
We hope this guide helped you get better acquainted with Saturn and will serve as a resource for you and your family during your next observing session. Do not forget to keep a watchful eye out in the next two months as Saturn and Jupiter moves closer and closer together for their historic super conjunction on December 21.
To browse Celestron telescopes and accessories that will make your Saturn viewing experience more enjoyable, please visit the Telescope section on our website.
Clear skies and happy observing!