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Saturn’s rings: Top tips for seeing

Telescopic image of Saturn with bands and multiple rings in pastel tones on black background.
View at EarthSky Community Photos. | Michael Teoh at Heng Ee Observatory, Penang, Malaysia, captured this image on July 21, 2021. He wrote: “This is my best Saturn image so far.” It’s a beauty, Michael! Thank you. Find our top tips for seeing Saturn’s rings below and read more about Michael’s photo.

Saturn’s rings are beautiful

Saturn is the most gasp-inducing planet when viewed through a telescope. And it’s currently providing its best views of 2022 as it reaches its August 14 opposition. Saturn looks starlike to the eye alone. It appears as a golden-hued dot and shines steadily, as planets tend to do. Binoculars will enhance its color, and even a small telescope will let you glimpse Saturn’s rings. Veteran observer Alan MacRobert at SkyandTelescope.com has written:

The rings of Saturn should be visible in even the smallest telescope at 25x [magnified by 25 times]. A good 3-inch scope at 50x [magnified by 50 times] can show them as a separate structure detached on all sides from the ball of the planet.

Want to see Saturn’s rings? First, you need to find Saturn in the sky. It’s not hard! It’s currently in the southeastern sky not far from the horizon after sunset.

White dots for Saturn and constellation Capricornus with green line showing ecliptic.
On August evenings in 2022, Saturn is in front of the faint constellation Capricornus the Sea-goat. At its August 14 opposition, Saturn rises in the east at sunset and is visible all night. But a bright moon is also in the sky then. If you wait until later in the month, Saturn will rise just after sunset in a darker sky. And if your sky is truly dark, you can use Saturn to guide your eye to the faint “arrowhead” shape of Capricornus in our sky. Chart via John Jardine Goss/ EarthSky.

Attending a star party or astronomy club

Okay, got Saturn? Now … about that telescope. One possibility is to start scouting out a star party near you, where amateur astronomers are set up to show you telescopic objects. Check the club map at NASA’s Night Sky Network to find star parties. Or try this list of astronomy clubs by state from the Astronomical League. You can also call a local university or science museum and ask about star parties. Or maybe a neighbor, or friend, has a telescope stashed in a closet? More possibilities:

Astronomy Clubs Near Me & Organizations, from SkyandTelescope.com.

2022 Astronomy Club Directory, from Go-Astronomy.com.

Astronomy Clubs Near Me, from LoveTheNightSky.com.

Once you can find Saturn in the sky and have a star party to attend, consider the following tips before your ring-viewing session.

Saturn's rings with light gray band, gap and dark gray band around the planet on black background.
When you look at Saturn through a telescope, even when it’s at its best, you’ll have to look carefully – and have excellent seeing – to glimpse the planet like this. James Martin in Albuquerque, New Mexico, caught this photo of Saturn at its 2017 opposition, when the rings were maximally tilted toward Earth. The 2022 opposition will happen on August 14.

Tip 1: You need a telescope to see Saturn’s rings

Don’t expect to see the rings in binoculars. You really do need a telescope. A bigger telescope will show you more than a smaller telescope. Check out the contrast between the two photos below.

Two slightly fuzzy images of Saturn, the bottom one larger and more distinct with visible bands.
These images suggest how the ringed planet Saturn might look when seen through a telescope with an aperture 4 inches (100 mm) in diameter (top) and through a larger instrument with an 8-inch (200 mm) aperture (bottom). Image via SkyandTelescope.com/ NASA/ Hubble Space Telescope.

Tip2: Consider the tilt of Saturn’s rings

Notice the tilt of the rings. As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In 2017, the north side of the rings opened up most widely (27 degrees), as seen from Earth. That’s the most open this side of the rings has been since 1988.

In 2022, the angle is down to 14 degrees but still very easy to see the expanse of the rings as we look at the planet’s northern hemisphere. By 2025, the rings will appear edge-on as seen from Earth. Because the rings are so thin, Saturn may look as if it has no rings at all! After that, we’ll begin to see the south side of Saturn’s rings, which will gradually increase to a maximum inclination of 27 degrees by May 2032.

28 views of Saturn, some with wide rings and some with edge-on rings.
The tilt of Saturn’s rings has a great impact on the planet’s overall brightness as seen from Earth. In years when Saturn’s rings are edge-on (2009 and 2025), Saturn does appear considerably dimmer. A computer program by Tom Ruen simulated these Saturn views. Image via Wikimedia Commons.

Tip 3: Can you see the rings in 3D?

Ask yourself … do Saturn’s rings look three-dimensional? Again quoting Alan MacRobert at SkyandTelescope.com:

Saturn has a more three-dimensional appearance than any other object in the sky; at least that’s how it looks to me with a 6-inch ‘scope on a night of fine seeing.

Shadows cast by the ring on the planet in front and by the planet on the farther ring can make the image of Saturn pop.

Tip 4: How’s the seeing?

What was Alan talking about in that quote above when he mentioned seeing? Both amateur and professional astronomers talk about the night’s seeing, which affects how clearly and sharply you can see a telescopic image. Seeing isn’t a quality of the telescope; it’s a quality of the air above you. It’s the reason the stars twinkle more on some nights than others.

When the air is particularly turbulent, astronomers say there’s bad seeing. The images in the telescope shimmy and dance. When the air is particularly still, astronomers say there’s good seeing. Seeing can shift from moment to moment as parcels of air move above you. So, as you’re gazing at Saturn, stand as quietly as you can – for as long as you can – and just look. You’ll notice moments when the image suddenly comes into sharper focus.

Diagram: line of sight bent by moving air on left, moving dots in circle on right.
Turbulent air makes for poor seeing. But the air above you can also “settle” suddenly. When viewing Saturn, wait for those moments. Image via AstronomyNotes.com.

Other tips to consider

Once you get comfortable viewing Saturn – assuming you’re able to view it again and again, with a telescope of your own – you’ll begin to notice details in the rings.

Today, thanks to spacecraft, we know that Saturn’s rings are incredibly detailed. But, as you stand at your telescope gazing upward, you might be thrilled to witness just one primary division in the rings, the Cassini Division between the A and B rings, named for its French discoverer Jean Cassini.

Seeing this dark division is a good test of the night’s seeing and your telescope’s optical quality, and also of your own eyes’ ability to simply look and notice what you see. By the way, if you’re looking at the rings – which means you’re viewing Saturn through a telescope – also look for one or more of Saturn’s many moons, most notably Titan.

The Opposition Surge

A phenomenon that occurs when Saturn is at opposition is that the rings brighten for a few days. You can only see this a few nights on either side of opposition, which this year occurs on August 14.

This is the Seeliger Effect, which Hugo von Seeliger first described more than 100 years ago. Normally the rings appear as bright as the globe of the planet. But as the planet lines up with the earth and the sun, more sunlight suddenly gets reflected back to us from the rings than from the globe, and the rings take on an additional level of brightness.

The two mechanisms for this brightening are shadow hiding and a coherent reflection of sunlight off of the rings’ particles. Shadow hiding occurs because the shadows are the shortest on the ring particles. The coherent reflection of light occurs because light going straight into the ice particles reflects off of the inner surfaces, then straight back to where it came from.

This brightness surge lasts only a few days; see a study showing this increase. The window for this opportunity is August 12 through August 16. The full moon will be just south of Saturn on August 11, so it should be easy to find.

Have fun!

Large, clear, sharp view of large yellowish banded Saturn with many rings.
Alas, you won’t see Saturn look like this through a telescope. This is a spacecraft view, from Cassini in 2016, showing Saturn’s northern hemisphere. Image via NASA/ JPL-Caltech/ Space Science Institute.

Bottom line: If you want to see Saturn’s rings, August 2022 is a great time to look. Grab a telescope and read the tips found here!

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The post Saturn’s rings: Top tips for seeing first appeared on EarthSky.

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