Debris from a ringed planet, and believability

Question

I am writing a fantasy book, so while I am not too concerned with being completely scientifically accurate, I would at least like for aspects of my world to feel believable, so as to not take the readers out of the story.

In short, my story is set on a ringed planet. The planet is Earth-like, and the ring is rocky. My main question is, would meteor strikes be more common as a result of fallen debris from the rings, and if so, in which areas would it be more common? I.e would areas directly below the ring be more prone to meteor strikes? This is important for my story, as some of the rocks in the ring contain a mineral called valtium that can be used for magic.

This leads me to my second question, which is regarding believability. Since the majority of the planet's surface is water rather than land, it follows that, if ring debris were to fall, most would end up in the ocean. My story follows a character who is a part of an ocean crew sent to find rocks that contain valtium. Due to their glow, they are easy to spot. The valtium is then collected by sending someone to dive down into the depths (using magical gadgets to stay alive, of course) to hack away at the rock so as to seperate the valtium, which is then lifted up into the boat. It's been a while since I took high school physics, so I'm not sure how believable this concept is, or which aspect I should revise. The one limitation I've thought of is that the boat has to be pretty close to the surface, as doing this in the middle of the ocean would be difficult to explain away even with magic, given the extraordinary depths.

Answer 1

The nice thing about this sort of premise is that we have wiggle room on both the hard science side and the magic side.

As far as the rings go, remember that planetary rings are transient, but on an astronomical timeline. With a planet like Saturn, the rings will be around for the next few million years at least. That doesn't preclude debris—Saturn has enough dust fall into its atmosphere to fill about an Olympic pool every half hour—but the larger objects are relatively stable. The most likely way to have them knocked out of orbit would be interference by external sources, like comets or meteors, or (if you want to get a bit more fantastic) solar flares and solar winds.

That said, this is already a sci-fi/fantasy setting, so I don't think having a few rocks fall out of the rings every so often even strains credibility; I wouldn't blink at such a premise. You could come up with reasons why they're cyclical or more common than usual: maybe the planet moves through an asteroid belt every so often or a comet crosses by, dislodging some of the ring. Maybe the star's solar flares sometimes affect the magnetic field of the planet, pulling a few of the larger/more potent rocks down. Maybe you could even work in the dust—since everyone on the planet is breathing in minute quantities of the dust through the atmosphere, maybe that's why humans have the potential for magic, or why certain species of flora/fauna exhibit fantastic traits.

Regarding deep-sea mining, there are a few similar options you could use. You could simply have the majority of the rocks fall into the oceans, but a percentage will still fall on the land or nearby. With such magical power available, there will surely be people who both have resources to monitor the arrival of the meteors and who will attempt/come up with new ways to go after previously-inaccessible deposits. You could also do a bit of hand-waving and some magicbabble about how the magnetic field is dampened by the oceans but strengthened by the ores concentrated in the continents, causing rocks to fall near to/on top of the land more often.

Or you could just not mention or worry about any of this! Honestly, this is all perfectly believable and I'd be fine with any of these explanations, or even without any. Not everything needs to be justified or explained in-universe, and the audience will be glad to accept some things and suspend their disbelief for the basic premise if it's simple and reasonable enough.