fbpx

How to See Saturn Through A Telescope

Seeing the planet Saturn through a telescope is one of the biggest pleasures available to backyard astronomers.

If you own a scope of 6 inches or smaller, then keep reading to learn how to find the ringed planet and what you should aim to observe when you do.

nasa picture of saturn
Saturn, 17x larger than Earth, but much less dense (NASA)

Saturn is the second largest planet in our solar system. It is slightly squashed and has a polar diameter of 67,560 miles (108,728 km), and a equatorial diameter of 74,898 miles (120,536 km).

In comparison, Earth’s diameter is only 3,963 miles (6,378 km), making Saturn more than 17 times bigger!

While it’s mass is 95 times that of earth’s, Saturn’s density is only 0.69 g/cm3. Water has a density of 1 g/cm3 so Saturn would float if there was a water body big enough to hold it.

Even though Saturn’s average distance from the Sun is 890,424,928 miles (1,433,000,000 km), it’s large diameter means it’s big enough to be seen from earth with the naked eye. Saturn’s angular diameter ranges from 14.5arcseconds to 20.1″, depending on how close to us it is.

(Learn more about degrees, arcminutes and arcseconds in this article. Opens in a new tab.)

Keep in mind that Mars’s angular diameter ranges from 3.4” to 25.1”. Saturn will always appear larger than Mars at its smallest, but never larger than Mars at its largest.

The magnitude of Saturn’s disk varies from a dim +1.5 to a bright -0.2. If you take the rings into account, the magnitude varies from a faint +1.17 when the rings are the least inclined to a bright -0.55 when the rings are most inclined. We’ll talk more about that later in the article.

When Is Saturn Visible?

The ringed gas giant is visible throughout 2019, other than January and the very end of December.

It presents its best views at opposition on July 9th, when it will be visible all night and reaches its highest in the sky around midnight. Although its 18″ disc is not on the same scale as Jupiter’s 46″ at opposition, it is still a bewitching sight to glimpse.

After opposition, the planet steadily falls into evening skies. By September, viewing is still great but Saturn sets a little after midnight. In November, Saturn sets at 9pm, but dark evenings will still let us get good views of her.

To find out more detail on when Saturn is visible, check out our detailed guide to when the planets are visible in 2019.

How To Find Saturn In A Telescope

Step 1 – Is Saturn in the Night Sky Tonight?

Like most celestial objects, Saturn spends part of the time unobservable because it is below the horizon during the hours of darkness, or above the horizon during daylight.

Thankfully, in 2019, the planet is visible in the evening (i.e. at least part of the time between sunset and midnight) from opposition in July to the middle of December.

You will always find Saturn on or near the ecliptic, which is the line all the planets appear to follow against background stars in the night sky. And, as the below screen grab from Sky Safari, shows, Saturn resides in the constellation of Sagittarius for the whole of 2019.

Click image for full screen version.

This particular shot is on the day of opposition, 9th July, just after midnight, and shows Saturn about 18° above the southern horizon. You can also see Jupiter off towards the southwest. Background stars are shown to magnitude 5.0.

For a more detailed look at where to find the planet for your location at the time you will be observing, refer to night sky software. A free version, like Stellarium, will show you where to look, as will paid software like Sky Safari.

To use Stellarium, set the time you plan to observe and your location. Next, search for Saturn and the planet will be centered in your viewing window.

For Sky Safari the process is even simpler. Use the search box to select and locate Saturn. When you have it, press the ‘i’ button for information about the planet.

Once you know Saturn is visible, we need to find it.

Step 2 – Finding Saturn Without a Telescope

As we said earlier, Saturn is big and bright. It’s the fifth brightest object in the sky after the moon, Venus, Jupiter and Mercury.

Start your viewing adventure by finding Saturn with your naked eyes. Use the sky plan from your software, or the monthly guide from Sky & Telescope Magazine to help you locate it.

Remember, the horizon is 0° and directly overhead is 90° and midway between the two is 45°. If you’re not sure on angles, use these hand shapes to make it easier.

If you look in roughly the right place, Saturn will always be one of the brighter ‘stars’ you can see. It shines with a pale yellow color, and pointing even a small telescope at it will confirm – without a doubt – that you’ve found the right object.

Step 3 – Finding Saturn with a Small Telescope

Now we turn to the good bit: seeing this gas giant through your telescope.

Although the planet will stand a good deal of magnification, it’s best to start with lower levels. This increases the field of view which makes it easy to get the planet in sight before you begin to zoom in and study more details.

Assuming you have correctly set up your finderscope, all you do to get Saturn in view is center it on the bright ‘star’ you identified in step 2.

A glimpse in your eyepiece will quickly show whether you have a planet in view. Unlike stars, which all stay as tiny pinpricks of light, Saturn has a distinct, solid shape.

Expect to see a flattened disc with two protrusions or ears (one on either side). These protrusions are the rings, which are 2.25 times as wide as Saturn’s disc.

Move your focuser to get the planet and rings in sharp focus and catch yourself gasp in awe at the majesty of this stunning, otherworldly planet.

If you’re not quite sure what to expect, or you’d like more confidence that you’ve found the right thing, this website has some simulated images of what Saturn looks like through different telescope sizes.

Targets to Look For When Observing Saturn With a Small Telescope

Now you have Saturn in the eyepiece of your small telescope, what should you be looking at?

Saturn has three great targets for small telescope observation. The first is Saturn’s rings. Secondly, there is Titan, Saturn’s largest moon and, finally, seeing any surface features on the planet itself.

We’ve given you more detail and resources for each below.

Target 1: How to See Saturn’s Rings

The feature for which Saturn is best known, her rings, are easy enough to see with the smallest of scopes. Even a 50mm diameter pair of binoculars will do the job if the sky is clear and dark.

Saturn orbits the Sun every 29.4 earth years and has an axial tilt of 27 degrees. The result of this is that the angle at which we see the rings changes over time in a cycle lasting about 15 years.

During that 15 year cycle, an earth-based observer will see a gradual shift from looking at the top of the rings, to looking at the rings edge on to looking at the bottom of the rings. This page includes an illustration of the changing orientation of Saturn’s rings between 1996 and 2000.

Seeing the rings now, when they are not far past their maximum tilt, is not a problem – they are quite unmistakable. The challenge to set yourself is seeing if you can distinguish different coloration in the bands.

In a slightly larger scope, with good seeing, you may be able to identify the broad color difference between the lighter, inner ‘B’ ring and the darker, outer ‘A’ ring.

Spot the difference in brightness between A and B rings (source)

Target 2: How to See Saturn’s Moon Titan

Titan is Saturn’s largest moon. At over 5,000 km across, Titan is more than 3 times larger than the next largest moons of Saturn, and it’s larger than Pluto, the earth’s Moon, and Mercury!

Even though Titan is far away, it’s large size means it’s a fairly bright and easy telescope target. This orange-brown target shines with a magnitude between 8.2 and 9.0 and orbits Saturn every 15 days.

Sky Safari, Stellarium, and this free resource from Sky & Telescope Magazine all show you Titan’s position relative to Saturn and it’s other large moons.

You may be surprised by how far apart Saturn and Titan are. Of Saturn’s 7 largest moons, 5 are closer to Saturn than Titan. If you are viewing from a sufficiently clear dark site, you may be able to see some of Saturn’s inner moons, as detailed in our article on Saturn’s moons.

Color image of Saturn’s largest moon, Titan (source)

Target 3: How to See Surface Features on Saturn

Just like Jupiter, Saturn has surface bands and experiences regular storms.

However, unlike Jupiter, we can’t see these in any detail from a smaller scope in our backyard.

The best we can hope for – and this is a challenge in itself – is noting changes in shading on the planet’s surface. You will to push your telescope and seeing skills hard. Use averted vision, and you might just see subtle shading across the surface of Saturn.

It may also help to use a telescope filter. Numbers 38A, dark blue and 80A, blue, could help tease out more detail.

Don’t worry too much if not, this last target may be too much for your scope and/or conditions.

Summary

Saturn is the second largest planet in our solar system and it’s rings make it an enticing target for backyard astronomers.

Observing the changing aspect of the rings and Saturn’s largest moon Titan bring an additional challenge to the sheer joy of seeing this unique planet.


Written by Tanya C. Forde


Hi, I'm Adam, the Astronomer Behind Love the Night Sky

Sign up for my FREE 5-day Beginner's Guide to Astronomy

close

Free 5-day Backyard Astronomy Course

If you'd love to see more with your telescope, our FREE mini-course is exactly what you need. Over the next three days you'll discover:

  • check
    How to get the best results with your telescope
  • check
    What you need to know to find the planets
  • check
    Where to successfully see Saturn and her rings