I Why is the DM density near the sun so small?

AI Thread Summary
The discussion centers on the surprisingly low dark matter (DM) density near the sun, estimated at 0.35 × GeV/cm3, compared to the average DM density in the universe of 2.26 × 10−24 g/cm3. This indicates that the local DM density is approximately 3.6 times lower than the universal average. A participant expresses difficulty in finding references to explain this discrepancy and seeks assistance from knowledgeable forum members. An error regarding the units of density was corrected, clarifying the average density in the universe is indeed 2.26 × 10−24 g/m3. The thread highlights a need for further exploration into the factors influencing local DM density.
Buzz Bloom
Gold Member
Messages
2,517
Reaction score
465
This question arose in the context of another thread.
Wikipedia gives an estimated value for the DM density near the sun of
0.35 × GeV/cm3 = 6.2 ×10−25 g/cm3.​
The value of the average DM density in the universe
ρDM = 2.26 ×10−24 g/cm3.
https://en.wikipedia.org/wiki/Milky_Way - Bottom of list of Observation data​
This means that ρDM is approximately 3.6 times the density of DM near the sun.

I unsuccessfully have tried to find references that provide an answer to the question, but my skills are not up to the challenge. I am hopeful that one or more knowledgeable participants here the PFs can help me.

Regards,
Buzz
 
Last edited:
Astronomy news on Phys.org
The average density in the universe is 2.26*10-30 g/cm3, 4.5 orders of magnitude thinner than the local density. I guess you mixed cm3 and m3, as the number is equal to 2.26*10-24 g/m3.

http://pdg.ge.infn.it/2015/reviews/rpp2014-rev-astrophysical-constants.pdf
 
  • Like
Likes Buzz Bloom
Hi @mfb:
Thank you very much for spoting and letting me know about my careless error.

Regards,
Buzz
 

Thread 'Does it make sense to build new radio telescopes?'

TL;DR Summary: In 3 years, the Square Kilometre Array (SKA) telescope (or rather, a system of telescopes) should be put into operation. In case of failure to detect alien signals, it will further expand the radius of the so-called silence (or rather, radio silence) of the Universe. Is there any sense in this or is blissful ignorance better? In 3 years, the Square Kilometre Array (SKA) telescope (or rather, a system of telescopes) should be put into operation. In case of failure to detect...
View full post »
Thread 'Could gamma-ray bursts have an intragalactic origin?'

Thread 'Could gamma-ray bursts have an intragalactic origin?'

This is indirectly evidenced by a map of the distribution of gamma-ray bursts in the night sky, made in the form of an elongated globe. And also the weakening of gamma radiation by the disk and the center of the Milky Way, which leads to anisotropy in the possibilities of observing gamma-ray bursts. My line of reasoning is as follows: 1. Gamma radiation should be absorbed to some extent by dust and other components of the interstellar medium. As a result, with an extragalactic origin, fewer...
View full post »

Thread 'Our Beautiful Universe - Photos and Videos'

This thread is dedicated to the beauty and awesomeness of our Universe. If you feel like it, please share video clips and photos (or nice animations) of space and objects in space in this thread. Your posts, clips and photos may by all means include scientific information; that does not make it less beautiful to me (n.b. the posts must of course comply with the PF guidelines, i.e. regarding science, only mainstream science is allowed, fringe/pseudoscience is not allowed). n.b. I start this...
View full post »

Similar threads

Why low precision of the radius of Sun's orbit in MW?
Replies
15
Views
2K
I Constraints on Dark Matter in the Solar System
Replies
14
Views
2K
I New Paper Claims Primordial Black Holes Don't Explain Dark Matter
Replies
20
Views
3K
I Why is a statistical explanation for Baryon Asymmetry wrong?
Replies
2
Views
1K
I What Key Issues Should Cosmologists Address in the ΛCDM Model?
Replies
1
Views
3K

Hot Threads

Recent Insights

Back
Top