I’m curious to see what comes up in answer to this question. I’m not talking about ghosts or UFO’s or anything like that. I’m talking about objects (earthly or celestial) or phenomena that we have a name for, can observe, but simply cannot understand nor explain how it works, why it’s here or why it does what it does.
So is there something obvious that I’m overlooking? Or is there not anything?
Well…we do have a pretty decent rudimentary understanding of how it operates, don’t we? The roles stars and planets play, how fast its moving away from us…the types of gases stars burn…how long stars tend to “live”, the age of the Universe…
We don’t know why? I thought it was understood to be a function of mass?
The accelerating universe is one, I believe. I read an explanation that compared it to throwing a ball up in the air and instead of it losing speed and coming down, seeing it just keep gaining speed and going up and up.
A short list, and I might be wrong about some of these:
[li]We don’t know what gravity is. We know how it works out to so many decimal places, but we don’t know how it arises from fundamental particle interactions. Compare this to, say, electricity and light, which we know a lot more about thanks to quantum field theories such as quantum electrodynamics.[/li][li]We don’t know where matter gets mass. Again, we know how mass works, but we don’t know how it comes about; this is what the search for the Higgs boson is about.[/li][li]We have a pretty solid idea that the Big Bang happened, but we don’t know what was going on at the exact instant it did. (This may be stretching the OP’s point a bit.)[/li][/ul]Add to that the minor mysteries, like where the Japanese language came from and why some people act like that (for various definitions of ‘some people’ and ‘like that’), and you can conclude that there are still mysteries left in the world.
You need to distinguish between “solid explanations” and “weak explanations”. There are some things that have multiple, competing explanations, and others where many if not most scientists are not very happy with the only likely explanation.
“Dark Matter” and “Dark Energy” are examples of such. The existence of these is proposed to explain the observed behavior of the Universe, and Astronomers and Cosmologists are looking to find these things, but at present the words are mere place-holders. Other scientists are trying to come up with alternative explanations that don’t require these things we haven’t been able to observe.
On the other hand, you could just as well say that we can work out electromagnetism to so many decimal places, but we don’t know how it arises from the geometry of spacetime. I don’t know of any reason why particle interactions should be considered a superior sort of explanation to geometrical configurations.
And I really wouldn’t put dark matter in the same category as dark energy, either. Dark matter is actually fairly straightforward: There are some fundamental particles we’ve detected directly, and it’s not too big a stretch to suppose that there are also some we haven’t. Even though we’ve never detected them directly, though, there’s no reason to suppose the rules they follow are any different than for the familiar particles. With dark energy, by contrast, we’re pretty close to clueless.