(Ironically, I can thank FaustianRubix for bringing this topic to my attention when reading one of his bad-faith smear campaigns for entertainment. <3 u bby.)

On two notable occasions, RD has made reference to both Saturn when speaking about interstellar communication the old fashioned way:

Tell them you're from the world with the large moon that shows the sun's corona during the eclipse.

If they stare at you in disbelief, tell them it lies between the two other worlds where life never really took hold.

Then mention Saturn, the seventh with the Rings and the Hexagon at the planet's north pole.

And to gas giants being used as long range, self-sufficient interstellar craft

Some ‘wandering’ gas giants or ‘rouge planets’ are simply long range ships carrying their power source with them like an explorer with a heavy backpack.

The inexplicable magnetic fields an observer might encounter come from propulsion devices amplifying and directing phenomena that naturally occur.

They make pretty shapes on the poles while powering down.

Just saying.

And bear in mind that I said ‘some.’ I didn’t say ‘all.’ I keep on having to point out this shite to all the Slipknot season ticket holders here who couldn’t deign to read a complete sentence if it was tattooed right on their gobs.

I've never been too fond of Slipknot, but regardless, it seems to me that Saturn (the seventh planet if you count Ceres in your definition, perhaps), and its South Pole hexagon, could likely fit the bill for one of these long range craft.

And... maybe its powering down in some way? For what reason, I couldn't say.

To add to that, unlike what a certain person clearly too wise to fall for this "cult,"^/sarcasm-if-unclear has stated, that being that gas giants are a "collective mass of exactly that..gas," gas giants, believe it or not, have a core.

According to our savior from total ignorance (despite its short-comings) Wikipedia:

Saturn's interior is probably composed of a core of iron–nickel and rock (silicon and oxygen compounds). This core is surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and finally a gaseous outer layer.

And:

Electrical current within the metallic hydrogen layer is thought to give rise to Saturn's planetary magnetic field, which is weaker than Earth's, but has a magnetic moment 580 times that of Earth due to Saturn's larger size.

An artificial magnetic field is already something being considered for radiation protection for near-future spacecraft. Why not just scale it up and do it a bit more lowkey?

So, it seems entirely possible that Saturn could be some sort of craft that has been in Sol for quite a long, loooong time, constructed by technology far beyond our current reach, but readily available to interstellar civilizations.

Starship or not, ol' Saturn's radio emissions (which are on the electromagnetic spectrum) are quite interesting. Take a look.

https://www.youtube.com/watch?v=hWHLCHv4PiI