Which Planets Have Rings & What Are They Made of?

Probably everyone knows that Saturn has flashy circles around it because the image of this ringed planet is practically iconic. And yet, Saturn is not the only planet with the rings — most other gas giants in our solar system have them. Besides, scientists have discovered that asteroids may have circular discs, and so can exoplanets. Below, we explain which planets have rings, what these circles are made of, and how they are formed — based on what astronomers have established so far!

How many planets in the solar system have rings?

In our solar system, four of the eight planets, all located after Mars and up to the ‘ultimate border,’ have circular discs. Besides, each system is unique in its composition, structure, and visibility. But let’s start with the elephant in the room — how many rings does Saturn have?

Saturn

The solar system’s most famous ringed planet has the most intricate ring system, divided into seven main sections, each containing numerous smaller rings. These main sections hold thousands of individual rings, making it challenging to count them precisely.

Saturn’s circular discs are primarily made of water ice, but these chunks could be tiny and huge (with the bigger ones easier to observe). The ice gives these particles their bright, reflective appearance. The source of these particles is likely old asteroids that broke apart under Saturn’s powerful gravity, perhaps even some of its old moons.

Jupiter

What about the biggest planet in our solar system—does Jupiter have rings? Yes! Though not as visible as Saturn’s, Jupiter’s rings are primarily made of dust particles, making them faint and hard to see from Earth. Despite this, we’ve identified a complex ring system with three main parts: the Halo, the Main ring, and the Gossamer rings (two faint rings formed from moon debris).

Uranus

Uranus has 13 distinct circular discs, much darker than Saturn’s. These are primarily made of water ice mixed with a dark, carbon-based material, giving them a dull appearance. Unlike Saturn’s bright circles, Uranus’ rings are dark and less reflective.

Today, astronomers believe that Uranus’s circular discs formed from the debris of ancient moons that were shattered in collisions — so, it’s the same theory as with Jupiter and the most common answer to the question — why do planets have rings? But that’s not the only theory; it’s also possible that rings are leftover building blocks dating back to the time of planet formation — and, in Uranus’ case, this theory has many supporters.

Besides, as space news resource Orbital Today explains, some rings may be short-lived — that is, they may eventually form into planetary moons. There is even a theory that our Moon was once a circle of debris formed due to Earth’s collision with another planet, Theia. But that is a different story, so let’s return to the last solar planet on our list.

Neptune

Neptune has a faint, narrow, fragmented ring system with five main rings. The rings are made of small rocks and dust particles coated in dark, carbon-based material and have a dusky appearance. Like other planets, Neptune’s rings likely formed when celestial bodies crossed the Roche limit and were torn apart by the planet’s gravity.

But which planet has the most rings in our solar system? The record holder is still Saturn — and now that we have our ‘home’ planets covered, let’s venture beyond and learn what else scientists have found!

A planet with the most rings J1407b

In 2007, astronomers discovered a new object that could either be an exoplanet or a brown dwarf. Considering the 434 light-year distance from Earth, it is currently impossible to say which one exactly. Still, most scientists agree that the object, cataloged as J1407b, is an exoplanet, after all — especially considering that in 2012, a mass ring system was discovered around it, which is why this exoplanet is now nicknamed super-Saturn.

The system is impressive, with up to 37 distinct rings spanning around 120 million kilometers—200 times greater than Saturn’s environment. Since so much is unknown, it is hard to say anything about its ring composition, but most astronomers believe that J1407b discs are composed of dust and ice, similar to other planetary circles.

Besides the traditional ringed planets in our solar system and exoplanets far beyond, astronomers have also uncovered circular systems around asteroids closer to home. Chariklo, in Saturn’s outskirts, has rings, and so does Haumea, a dwarf planet in the Kuiper Belt. But there is good reason to believe that astronomers will discover more intriguing stellar objects as our telescopes advance — so stay tuned for more posts about the secrets of our Universe.

The author’s name is Emma Thorpe.