The limits...................

..........of our knowledge are actually fairly impressive.  Here is a list of seven unanswered questions about the Universe.  In face of what we don't know (and all that we thought we knew that turned out to be wrong), one would think we should be hearing a lot less about "settled science."   From the list:

5. We don’t know how the Earth works: Let’s lurch back to a grander scale. No human, or robot, has ever physically traveled deeper than a few miles into the Earth’s crust, everything else is extrapolation and interpolation from ‘remote sensing’ and clever physical analyses. It took us a ridiculously long time to figure out that the outer planetary skin is moving and sliding around; plate tectonics was not generally accepted until the mid-20th century! We’re still not sure exactly how the inner dynamo works, how rolls of convecting magma generate our planetary magnetic field.

There’s also so much mess after 4.5 billion years of geophysics that some of our best information about the planet’s origins come from meteorites and the cratering of other worlds — outsourced. Speaking of other worlds, we’re not even sure we understand where the Moon came from, maybe it was a giant impact, maybe not. For an allegedly clever species on a small rocky planet this is a bit of an epic fail.

For those of us who like their endings happy, here is the conclusion to the article:

There’s an awful lot we don’t know (far more than just the examples here). But the point is not to get despondent, because this ignorance is a beautiful thing. It’s what ultimately drives science, and it’s what makes the universe truly awe-inspiring. After the hundreds of thousands of years that Homo sapienshas loped around, the cosmos can still elude our fidgety, inquisitive minds, easily outracing our considerable imaginations. How wonderful.