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There's several neutrins detectors. They're in deep mines like Canadian gold mines. Neutrinos have been studied for quite some time. For decades there was a problem understanding the neutrinos that came from the Sun. There are 3 types. The wrong type of neutrino was observed coming from the Sun. The type of neutrino expected from solar hydrogen fusion was not observed in the right quantity. Later it was shown that the neutrinos can convert between types post reaction and the solar neutrinos were all accounted for.

"So this 'dark matter' stuff should be orbiting, or falling to, Earth and landing on my carpet."

They fly at the spped of light. The escape velocity from Earth's surface is ~11000m/s. The speed of light is 3*10⁸m/s. They'll always fly back off into space. Neutrinos can interact with nuclear matter, so they can interact. Their small x-section means they have a low probability of doing so. So, if they do inteact, it's always deep in the Earth as they fly through. Axions just fly through.

"or Jovian or solar gravity."

Larger objects are required to capture them into orbit. It's the collection of large objects in a galaxy, or black hole that can and does.

Larger objects are required to capture them into orbit.

So the gravity of the Sun is powerful enough to capture Jupiter, but it's not powerful enough to capture a sub-atomic particle. Do I have that right?

And even if these 'wimps' are traveling at near light speed, they should still be deflected by gravity the same way a bullet is deflected by Earths gravity. Newtons Laws apply to everything. Don't they?