the OP world has has 6 moons, and one of those moons has its own moon
personally, i think all those moons are the reason why the Grand Line has such weird weather. the gravity, magnetic fields, etc of each moon is interfering with each others. our moon is very important to weather on our earth. it causes high and low tides and balances the earth, and if we were to lose the moon, the weather would go insane.
so it’s possible the OP world has the opposite problem–TOO MANY moons, all pushing and pulling the water at their own pace, trying to create their own weather patterns, causing the Grand Line’s strange, unpredictable weather, slowing down and speeding up evolution, and creating weird magnetic fields (probably why compasses don’t work there).
i also think that one of these satellites is constantly reflecting light on Enies Lobby, which is why it’s always sunny there. and i think one of these moons is probably the reason why the Calm Belt has no wind.
Eneru is on one of these moons, and i think he’s on the very top middle one, because it’s the smoothest and the only one that makes sense. the others have weird textures which don’t match this moon at all (x-shaped things? spots? horizontal lines? not to mention the extra moon on one of them), and the one on the top left kinda matches, but looks too big to be the moon Eneru is on, and it has strange suction-cup like things that look too big to be craters.
we know that the moon Eneru landed on is where the Sky Island people originally came from, which explains Eneru’s strange obsession with the moon. We know these people lived on the moon, but had to leave because they ran out of resources, and they built robots using pretty advanced technology considering no one has been around for maybe 1000 years. (the ancient Shandorians had a Poneglyph which first appeared around 800-900 years ago, so it had to have been at least that long).
along the way, they all separated into different groups. the Bilkans (wide, downward facing wings) seemed to have founded their own Sky Island. That also happened to be the island Eneru first came from and then destroyed before the start of the series. the Shandorians came to the Blue Sea and founded a great city of gold, and they had SOMETHING to do with the Void Century. and the Skypeians created a Sky Island of their own.
oh, and Eneru now has an army of adorable robot warriors and he fought some space pirates. Aliens and space pirates are confirmed to exist in OP.
oh, and is it me, or does this thing that pulled Capone and his crew up, kinda look like this moon on Clover’s globe? the one with the suction cup things i mentioned earlier?
of course, Capone being sucked up into one of the moons is just a theory.
things we still don’t know: what those other moons might be, where those space pirates came from (maaaaybe from one of the other moons? we have confirmed life on one of them at least), why the moon people who became the Bilkans, Skypieans and Shandians split up, what connection the ancient Shandorians had with the Void Century and the Ancient Kingdom to faithfully protect a Poneglyph for 800 years, what all that technology on the moon is, and what Eneru is gonna do with his new found, adorable robot army