In game graphics & system map show 3 rings, the system map even lists A, B & C, but for the orrery & DSS the C ring doesn't exist as a separate entity.
The candidate number two Thaileia TM-A c2-0 body #7 -- class IV gas giant with enormously large (39,3 MKm) but rather sparse (about 20,3 tonnes per 1 km3) ring -- also turns out to be unspectacular.
But I still have 19 candidates with 30MKm+ rings for the galactic record
And of them the most promising candidate seems to be Droju QU-D d13-8 body #4 -- class IV gas giant with 34,7 MKm dense icy ring.
In the meanwhile I've prepared a list of currently known planets with shepherd moons and extra-large (30+ MKm) rings. There are not so many of them -- only 23 (and about 220 with 20+ MKm rings).
I've already checked some of them (with no success yet) trying to find ones with visible rings. I've marked with red font the ones I believe to be the most promising candidates.
I've reached my destination: system Droju QU-D d13-8 and right from the entry point I saw that it was a success.
Icy B-ring of the class IV gas giant #4 has radius of 34,7 MKm, which is, actually, almost a quarter of AU.
This is not the most spectacular ring I've seen, and this might also be not the biggest currently known planetary ring (because the biggest is this invisible one), however it still holds the record of being the biggest currently known visible planetary ring.
When "parked" at the very end of the ring, the parent body is 116 Ls away.
The system also has another planet with a notable ring:
The most interesting about it is, that both thin concentric rings actually count as one:
And that allowed me to make an experiment: I flew through the gap in SC, and despite the fact, that the map shows a single ring from 8,6 to 22 Kkm, I was not pulled out of SC.
And that actually means, that invisible rings may actually not be physically unexistent. If they consist of several thinner concentric invisible sub-rings with gaps between, the fact of not being pulled out of SC may actually mean that we just missed one of those thin sub-rings. And that time when I was pulled out, I might just be lucky to hit one.
Couldn't get a good shot from realspace. The rings are too far apart - in any shot wide enough to see both, the moons were indistinguishable from background stars.
Unfortunately both rings are too sparse to be seen. I've also tried hard to hit them both in SC, but had no luck.
On my way there I've payed a visit to a couple of more spectacular looking systems: Byeia Eurk ZC-S c5-9 with body #C 6 -- class I gas giant with 1,4MKm nice-looking icy ring and three shepherd moons:
OK, I found 3 moons between the 2 rings of a gas giant. I'll put up the system later, buuut I was trying to map the outer ring, but it's 4 ls from the planet and it won't let me shoot probes at it. Is there a trick I am missing? Or can we not map those?
According to my experience, there is no trick, we just can't map large rings and that's all. That is true not only for outer rings, but for all large rings in general, including ones like in Mylaifa AA-A h786. You can manage to make probe look like it passed through such ring, but it still won't map it.
I have been trying a new system of spotting which bodies have between ring moons and that's basically to check the gap between the rings in the system info screen. If the gap is only 100km, and most of them are, there won't be moons, if it's more than 100km then it's almost certainly a lot more than 100kms and a good chance of having moons there if the planet has moons. Hasn't failed me yet.
Also I have experimented with the outer rings in these systems and it's easy enough to fly through the small gaps in the rings in SC with no issues even at full throttle so they don't act as one homogeneous object as far as our ships are concerned. These bodies haven't been reported to UC yet but I am still 14kly away from the nearest station so thought I would report them anyway.
Cmdr. FalconFly reports one more nice gas giant: Flyue Dryai AT-K b27-5 body #7 -- class I GG with large B ring and shepherd moons.
And another oddball. A Gas Giant with a 2nd Ring that starts way beyond its 4 inner moons. Only a 0.04AU 5th Moon resides outside of that 2nd ring; sadly it doesn't intersect on its inclined Orbit.
Needless to say, that huge 2nd Ring might contain dozens of Hotspots - but is impossible to scan due to DSS refusing to fire probes (out of range).
Sorry, don't have an in-system picture of this one. I used a tool I wrote to scour my logs for moons inside rings and found this one that I came across six months ago.
And NGC 3199 Sector BG-X c1-4 #body 6 in Outer Orion Spur near NGC 3199 Nebula. By the way, this thing has not only shepherd moons but also two shepherd lagrange clouds on orbit of the closest moon
Planet 5 is a gas giant with 2 sets of rings and all its "children" moons between them. The 5 F moon seems to be a previously rouge planet caught by the planet's gravity. Because of that it is angled to the main plane of the rings and can create nice sceneries of the gas giant with all its moons inside the rings like little light sources.
So I went through my Journals since about 2018. Here's some other systems I know about that have Shepherd moons in them, but I don't have screenshots I'm afraid. Not sure how many of these you know about, so I'm going to just list them all here.