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ensalys t1_iu9cv7r wrote

Reply to comment by Insane212 in Is dark matter orbiting galaxies with the same speed as normal matter? by taracus

Depends on what you mean with "on Earth". We don't have an invisible mountain of dark matter somewhere on the planet. Considering it doesn't act on electromagnetism, it doesn't really collide, for the most part it would just go through Earth. But yes, dark matter is expected to be present in the solar system, though in tiny amounts. So occasionally some dark matter will go through Earth. How much is unknown, we'll need to a good understanding of what particles make up dark matter.

> If yes why have we not been able to study it

We try, but it's rather difficult due to it no interacting (often) with detectors.

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Kered13 t1_iuaw5ft wrote

> So occasionally some dark matter will go through Earth. How much is unknown

It's actually pretty easy to estimate. Since we know the average density of dark matter in the galaxy, and we know that it's essentially uniformly distributed (it doesn't clump up like regular matter), we know that the density is the same around Earth. It's negligible compared to the mass of the earth, but enough that you can assume there is constantly dark matter passing through your body.

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ensalys t1_iucexdk wrote

Sure, you can do that. However, to really estimate how often that happens, we need to know the mass of individual bits/particles of dark matter.

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