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How Many of Saturn’s Moons Can I See Through a Telescope?

When you’ve seen the spectacular rings of Saturn through a telescope, the next obvious feature to look for is its moons.

They present a great target because there are so many of them but a common question is: “How many of Saturn’s Moons can I see through a telescope?”

We’re going to answer that for you here.

How Many Moons Does Saturn Have?

Saturn has 53 confirmed and named moons.

Saturn's  smallest and unconfirmed moon
A tiny and unconfirmed moon of Saturn (NASA)

A further nine moons are provisional. At least one of those will remain that way until there’s another fly-by of Saturn.

In total therefore, Saturn has 62 moons discovered…so far.

Saturn’s 62 satellites span a spectrum of sizes from over 5,000 km across, to the unnamed satellite in the picture above, which is just three football fields wide!

It’s the size and reflectivity of Saturn’s moons which determines how many of them we can see here on Earth through a telescope.​

Saturn’s Biggest Moon: Titan

Titan is Saturn’s biggest moon, and by some margin.

In fact, if were not for Ganymede which orbits Jupiter, Titan would be the largest moon in the solar system.

The comparison below gives a sense of how big Titan really is. Comfortably larger than Mercury and our own moon, and twice the diameter of Pluto:

  • Titan: 5150km
  • Mercury: 4880 km
  • The Moon: 3475 km
  • Pluto: 2360 km

Titan is a beast of a satellite, and, for that reason, it is the easiest of Saturn’s moons to see through a telescope.

But, what of the others..?

Saturn’s Next Biggest Moons

We’ll limit our conversation here to those moons we’re likely to find with a decent amateur scope.

We used this calculator to learn that a 6” reflector used under decent skies can show objects down to magnitude 13.5.

Assuming you have at least that power, there are six of Saturn’s other satellites (excluding Titan) within reach of your telescope. These are Saturn’s biggest moons but none of them is close to the size of Titan.

From nearest to Saturn outwards, the largest of Saturn’s moons are:

NameSizeMagnitude
Mimas397 km12.5
Enceladus499 km11.5
Tethys1,060 km10
Dione1,118 km10
Rhea1,528 km9
[Titan]5,150 km8
Iapetus1,436 km10.5

How Many of Saturn’s Moons Can I See Through a Telescope?

There are seven of Saturn’s moons which you can see through a 6” reflector under dark skies. In order of difficulty, starting with the easiest (brightest) first, they are: Titan, Rhea, Dione, Tethys, Enceladus, and Mimas.

How to See Saturn’s Moons Through a Telescope

To see the moons of Saturn through a telescope you will need an almanac to plan your best viewing time.

Although it looks dull, it’s just a long column of numbers, this Saturn almanac from the United States Navy is definitely the best we’ve found. It identifies the greatest elongation of the brightest moons of Saturn making it simple to plan your own viewing.

There are two ways to use it:

  1. Pick the day you plan to observe and see what is out, or
  2. Decide which of Saturn’s moons you’d like to ‘discover’ for yourself. Scroll down to your chosen satellite and plan the best night for observing them.

Where To Look For Saturn’s Moons

Saturn’s moons are faint, small and wander a long way from their central planet.

The screen grab below, from SkySafari 6, shows just how tricky it is to spot these tiny rocks so far away.

screen grab from sky safari showing 5 of Saturn's largest moons orbiting the planet
Titan, Tethys, Dione, Rhea and distant Iapetus in a 1/4° circle (click to enlarge)

The blue circle in the image is a ring just 0.25° in diameter. The points of light you seek are minute and will require patience and good seeing to discover.

When Can I See Saturn?

Before you start looking for Saturn’s moons, you need to find Saturn itself. To discover when Saturn is in the night sky, take a look at our guide to the visible planets.

If you need a better telescope to see Saturn’s moons, then read our guide to the best telescopes for seeing the planets.

Summary

Saturn has over 60 satellites which we’ve discovered so far. Most are tiny – far too small for us to see as backyard observers.

One is huge: Titan is the second largest satellite in the solar system, dwarfing our own moon and even Mercury and Pluto. Shining at magnitude 8, it is relatively easy to see. The next 6 largest are within reach of a 6″ telescope under dark skies, but are not easy.

Try your skills out first with Titan and, after that, see how far down the size range you can progress.