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A comment on The Reason We Haven’t Directly Detected Dark Matter. Parent comment

Re:The Reason We Haven’t Directly Detected Dark Matter by mikekchar on Saturday October 13, 2018 @10:18AM (#18208051)
But even then, there's no reason to assume that there is any in that space. For example, imagine that all the dark matter was in a disk around the solar system, way out farther than the asteroid belt. If you could see through it, you would never know. Or maybe it rings galaxies. Or maybe it hangs out in clumps between galaxies. Or... It literally could be anything because we can only measure it on the scale of mind boggingly massive structures.
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Re:The Reason We Haven’t Directly Detected Dark Matter by saagarjha on Saturday October 13, 2018 @06:52PM (#18210438)
I believe it’s generally believed that dark matter clumps near galaxies because it interacts through gravity. So would it be reasonable to say that it should clump together near massive objects in the solar system?
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Re:The Reason We Haven’t Directly Detected Dark Matter by pas on Saturday October 13, 2018 @08:33PM (#18210731)
DM usually forms a halo as it orbits the center of mass of whatever it orbits (galaxy, globular cluster), and because it doesn't interact otherwise, it cannot slow down, cannot shed momentum, so it is likely mostly not a disk, but a big sphere, and probably a shell around galaxies.
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Re:The Reason We Haven’t Directly Detected Dark Matter by ianai on Sunday October 21, 2018 @12:16AM (#18266705)
That sounds a little like an additional dimension or alternative something truly “out there”. Ie maybe gravity’s force relies on some process that reverses at the macro scale.
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Re:The Reason We Haven’t Directly Detected Dark Matter by MauranKilom on Sunday October 14, 2018 @08:57PM (#18216630)
I mean, If there were appreciable amounts of it (i.e. not on the scale of kilograms in or around the earth), so that it could have a measurable impact on planet orbits, we could gain information on its distribution within (or interaction with) the solar system. That's why this density estimate is interesting - it sort of determines what the smallest scale is at which we'd have a chance of observing interactions/structure with dark matter.
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