Is Dark Matter Only Present on a Galactic Scale?

[alvarogz]

Why doesn't dark matter affect the movement of solar system bodies as it does with the galaxies and stars movement?. Is it possible that dark matter affects only at galaxies scales or that the heliosphere interferes with the interaction of dark matter at solar systems scales (I say this because the measurements of the orbits of solar system bodies are very precise)?.

I was watching BBC.Horizon.2006.Most.of.Our.Universe.is.Missing when the question came up. Thanks.

 

[DaveC426913]

I say this because the measurements of the orbits of solar system bodies are very precise

How precise?

 

[alvarogz]

enough precise to calculate the orbit of planets, moons, comets, asteroids, etc. That's why we have artificial satellites orbiting the Earth and other planets... What I'm trying to say is if the influence of dark matter is applicable to the orbit of solar system bodies or not. If the answer is NO, I'm wondering why? if this dark matter is a kind halo that sorrounds the galaxy and gives it the rest of the mass that explains its movement.

 

[DaveC426913]

enough precise to calculate the orbit of planets, moons, comets, asteroids, etc. That's why we have artificial satellites orbiting the Earth and other planets... What I'm trying to say is if the influence of dark matter is applicable to the orbit of solar system bodies or not. If the answer is NO, I'm wondering why? if this dark matter is a kind halo that sorrounds the galaxy and gives it the rest of the mass that explains its movement.

You'd need to determine how dense the dark matter would need to be to show the effects it is showing on the galaxies. Then you'd need to show whether that density would have any effect on such as small scale as the solar system.

And I do believe the the dark matter is not evenly distributed throughout a galaxy. That's why it's not rotating as expected.


Here's an unrelated effect to chew on when thinking about scaling forces: expansion of the universe happens on a very large scale - it happens between galaxies and galaxy clusters. We do not see its effect within galaxies and certainly not within our solar sytem. It is simply far too small to overcome the effects of gravity.

 

[alvarogz]

You'd need to determine how dense the dark matter would need to be to show the effects it is showing on the galaxies. Thne you'd need to show wherher that density would have any effect on such as small scale as the solar system.

And I do believe the the dark matter is not evenly distributed throughout a galaxy. That's why it's not rotating as expected.

I thought about density of the dark matter as way to explain its possible marginal gravitational effect over a solar system, considering its little size, compared to the vast dimension of the interstellar space and the whole galaxy. Probably at minor scales the effect is less than in bigger scales.

 

[Janus]

enough precise to calculate the orbit of planets, moons, comets, asteroids, etc. That's why we have artificial satellites orbiting the Earth and other planets... What I'm trying to say is if the influence of dark matter is applicable to the orbit of solar system bodies or not. If the answer is NO, I'm wondering why? if this dark matter is a kind halo that sorrounds the galaxy and gives it the rest of the mass that explains its movement.

The amount of dark matter estimated in the entire Solar system is only estimated to be about 10^20 kg or about 1/9 the mass of the asteroid Ceres.

 

[alvarogz]

very interesting information. if that data is correct we can assume that dark matter and, off course, its gravity, governs at bigger scales.
You mean Ceres, the dwarf planet...? So, its a very little amount of dark matter that is interacting at our solar system.

 

[mathman]

very interesting information. if that data is correct we can assume that dark matter and, off course, its gravity, governs at bigger scales.
You mean Ceres, the dwarf planet...? So, its a very little amount of dark matter that is interacting at our solar system.

Also the dark matter is pretty evenly spread out within the solar system, so its gravitational effect would be extremely negligible.