ScienceNOW: For decades, most astronomers and astrophysicists have believed that each galaxy lies within a vast cloud of dark matter--mysterious stuff whose gravity holds the galaxy together but has never been detected in any other way. Now, new simulations refine that picture, showing that within the familiar spherical cloud there lurks a superimposed disk of dark matter that itself contains the galaxy's vast swirl of stars. That disk-within-a-sphere picture suggests that the solar system may be cartwheeling through space with an accompanying fog of the strange substance, which could make it easier for researchers to spot dark-matter particles using supersensitive underground detectors.
This computational model that suggest that a disk of Cold Dark Matter is superimposed within the Cold Dark Matter galactic halo and on the visible matter disk of stars and baryonic matter interstellar gas is great numerical detective work.
One thing that I wonder about and would like to believe is the possibility that there may be as many as 5 or 6 different types of Dark Matter or classes of Dark Matter species.
The fact that baryonic matter seems to make up only 1/5 to 1/6 of the mass-energy content of our universe wherein the total of this material based mass-energy is only about 28 percent of the total energy content of our universe (the remaining 72 percent existing in the form of the yet more mysterious Dark Energy), begs the question as to whether the particulate form of mattergy is composed of roughly 28/5 or 28/6 types of dark matter since such a particle class distribution would display a certain eveness in the distribution of dark matter verses such would be particle classes in terms of class relative total mattergy content of the particulate matter.
Note that the ratio of 28%/5 and 28%/6 is roughly 4.6% which is the amount of baryonic matter contained within the universe according to the experimental/observational results of the WMAP Probe.
An alternative way to consider the observational findings is to form the ratios 72/23 and 23/4.6 which are roughly on the same order of magnitude. The values of 100/23 and 28/4.6 are also of roughly the same order of magnitude to each other perhaps suggesting that there is only one fundamental type or class of dark matter particle. The reasoning behind this conjecture, in the first case, by symmetry is the consideration of the rough equality of the ratio of the percentage of the total universe energy in the form of dark energy (72%)and that of the particulate dark matter (23%) and the ratio of the percentage of dark matter (23%)and that of baryonic or visible matter(4.6%). In the second case, the argument by symmetry is the rough equality of the ratio of the total energy content of the universe (100%) and that of the dark particulate matter-energy content (23%)to the ratio of the total particulate matter-energy content of the observable universe (28%) to that of the baryonic or visible matter content (4.6%) of the universe.
Note also that the ratios of 100/23 and 23/4.6 are also close in value to each other.
The value 100/28 is roughly one half that of 28/4.6 thus perhaps suggesting the existence two classes of cold dark matter particles, because of the close matching of the relative size of these two values with the relative size of the two terms in the series 1/n and 2/n respectively. One might even argue that there is some fundamental reason why the relative values of 100/28 and 28/4.6 are close to that of 1/n and 2/n. Nature for some obscure or fundamental reason may have chosen this relationship and/or the relationships between the ratios discused in the previous paragraph for some fundamental reason.
Thus, there may be some relatively simple but obscure and fundamental relationship between the relative abundance of the forms of matter energy within our universe. The dark energy content, dark matter content, visible baryonic matter content and the total particulate matter energy content of our universe may be related in an existential or casual manner through some sort of casual coupling mechanism.