Milky Way Appears to be Void of Dark Matter --"The Mystery of Dark Matter Deepens --A New Solution for the Missing Mass Problem Must be Found."

 

         

The most accurate study so far of the motions of stars in the Milky Way has found no evidence for dark matter in a large volume around the Sun. According to widely accepted theories, the solar neighbourhood was expected to be filled with dark matter, a mysterious invisible substance that can only be detected indirectly by the gravitational force it exerts. 

A new study by a team of astronomers in Chile has found that these theories just do not fit the observational facts. This may mean that attempts to directly detect dark matter particles on Earth are unlikely to be successful.

A team using the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory, along with other telescopes, has mapped the motions of more than 400 stars up to 13 000 light-years from the Sun. From this new data they have calculated the mass of material in the vicinity of the Sun, in a volume four times larger than ever considered before.

“The amount of mass that we derive matches very well with what we see — stars, dust and gas — in the region around the Sun,” says team leader Christian Moni Bidin (Departamento de Astronomía, Universidad de Concepción, Chile). “But this leaves no room for the extra material — dark matter — that we were expecting. Our calculations show that it should have shown up very clearly in our measurements. But it was just not there!”

Dark matter is a mysterious substance that cannot be seen, but shows itself by its gravitational attraction for the material around it. This extra ingredient in the cosmos was originally suggested to explain why the outer parts of galaxies, including our own Milky Way, rotated so quickly, but dark matter now also forms an essential component of theories of how galaxies formed and evolved.

According to current theories dark matter is estimated to constitute 83% of the matter in the Universe with the remaining 17% in the form of normal matter. A much larger amount of dark energy also seems present in the Universe, but is not expected to affect the motions of the stars within the Milky Way. All attempts so far to detect dark matter in laboratories on Earth have failed.

By very carefully measuring the motions of many stars, particularly those away from the plane of the Milky Way, the team could work backwards to deduce how much matter is present. The motions are a result of the mutual gravitational attraction of all the material, whether normal matter such as stars, or dark matter.

Astronomers’ existing models of how galaxies form and rotate suggest that the Milky Way is surrounded by a halo of dark matter. They are not able to precisely predict what shape this halo takes, but they do expect to find significant amounts in the region around the Sun. But only very unlikely shapes for the dark matter halo — such as a highly elongated form — can explain the lack of dark matter uncovered in the new study.

The new results also mean that attempts to detect dark matter on Earth by trying to spot the rare interactions between dark matter particles and “normal” matter are unlikely to be successful.

“Despite the new results, the Milky Way certainly rotates much faster than the visible matter alone can account for. So, if dark matter is not present where we expected it, a new solution for the missing mass problem must be found. Our results contradict the currently accepted models. The mystery of dark matter has just become even more mysterious. Future surveys, such as the ESA Gaia mission, will be crucial to move beyond this point.” concludes Christian Moni Bidin.

The Daily Galaxy via ESO

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Comments

[nbi]

if the general relativity doesn't work with nano scale and the more sophisticated quantum physics must be considered, why don't scientists consider using different physics for very large cosmic and galactic scale to solve the mystery of dark matter?

[eco]

"why don't scientists consider using different physics for very large cosmic and galactic scale to solve the mystery of dark matter?"

tell me about it, im no physics expert but i hate to see unproven theories being treated as fact, sales interest education is a terrible thing, nobody questions anything anymore, everything is just accepted despite the awareness of our limited iq's, but i guess if it's in a book and dead people used to talk about it then it must be true :\

[Tosca Zraikat]

With all these new discoveries putting our theories into question, perhaps it is time to admit that we just don't know much. We know this or that about this or that phenomenon, but we are FAR from understanding how the cells in our body work, much less the cosmos. Instead of coming up with one theory after another only to replace them when they prove wrong, why not talk about possibilities, ideas, suggestions, and adopt the more wondering, playful, in awe-of-it-all attitude towards the great mysteries of life and being? Why not let go of our egoic need to show how smart we are (surely smarter than everyone else) and be thankful that we can understand anything at all in this wonderous cosmos?

[mrobvipus]

Wow, the people me are so smart. I wish the scientists coming up with all these dumb "theories" would just read those comments. I wonder why they never became astro-physicists...

[Asdf]

Scientists, listen.

To explain how galaxies function, you need more than 4 basic forces. Using gravity, electromagnetism and strong/weak nuclear is not enough to explain how is it that galaxies rotate as they rotate.

Only thinking out of the box will help you.

[PP]

"Dark matter" and "dark energy" are pre-scientific concepts to explain something that is simply not there. Some years from now people will wonder how such dumb theories came to be formulated by "scientists".

[Greg]

This is why it is a "theory". It is not the fact of dark matter. The "fact" is there are forces at work that we can't explain. The "theory" to try and explain these forces is dark matter, mysterious invisible stuff, that interacts gravitationally with visible matter.

Experiements are being done to try and prove or disprove this theory. This one is leaning toward disproving it. Once it is proven wrong or partially wrong or whatever, the theory will be replaced or modified to incorperate the new data. Its how science works.

[DrNeko]

"Dark Mater" is a hypothesis ... not a theory... When will writers and people get it straight?

[Bob Greenwade]

"'Dark Mater' is a hypothesis ... not a theory... When will writers and people get it straight?"

"Dark Mater" is the evil twin of a character in "Cars."

[Observer]

This missing mass issue was solved why are all these sill theories still being pushed around.
http://www.news.com.au/technology/aussie-girl-solves-amelia-fraser-mckelvie-mystery-of-universe/story-e6frfrnr-1226064604259

[john]

Thank you DrNeko...that's been driving me crazy for a while.

Scientific method:

1) Propose a hypothesis
2) Design experiment to test hypothesis
3) Develope a theory based on observational data
4) start over ...and over...and over
5) Keep refining theory to match observational data.

6) Even a proven theory is still a theory until a consensus
of scientist agree and it becomes a law...etc.....

[smartypants]

Bob Greenwade, we all ready knew you have a sense of humor from all of your post! MWAHAhaha

The main problem with how these stories are posted (like they are factual and absolute) misleads people that just dont know any better. The ones that really seem to bother me is when some one claims that "The Black Hole In The (or any) Galaxy Center" is up to what ever. Not one black hole has ever been proven to exist. Sure, there is something in the center of galaxys, and the theoretical black holes may be the best match to date, but that doesnt make them black holes. BUT to millions of readers that see this will swear on their lives there are black holes in all galaxy centers. As our astronomy tools get more advanced we will see much more BUT if we are all ready prejudiced against other possibilities, we may never see the truth.

[SB]

Nothing can actually be proven.

Everything can be disproved.

Our ability to measure anything can be questioned, if we live in a holographic universe maybe matter is only an illusion. The only way to find out is to keep asking questions.

[michael k]

Our understanding of physics is so minuscule, it as if we have discovered an iceberg. We think we know so much, but under the surface we know very little. How can we actually understand theoretical physics when we do not understand anything past the third dimension? We learn something new every day but at this rate, it will be a few hundred years before we know anything about dark matter, whether it exists or not, or if the matter that is missing in the universe was the result of black holes.

[Leonidas]

@Tosca Zraikat: Couldn't agree more!

@smartypants: Yeah, it irritates me a lot when everyone treats theories as fact. I have read so many astronomy textbooks that presebt dark matter as fact. I have even been to planetarium presentations (presentations created by scientists) that showcase the big bang and dark matter as proven truths. 500 years ago the truth was that the earth was flat. I understand that trial and error is the process of science. But to treat unproven concepts as fact is entirelly un-scientific.

@Asdf: It's exactly that out-of-the-box thinking that creates breakthroughs. And we sadly don't have a lot of it.

[James Ph. Kotsybar]

SCIENTIFIC EXEMPLIFICATION
-- James Ph. Kotsybar

Through realization
of observation,
one arrives at a presupposition.
Then, greater mental organization
of the addition
of information
makes a transition
to speculation,
which should lead to further inquisition.

By definition
this is cognition,
whic hfollows knowledge accumulation.

Next, proposition
of explanation
made from the data’s interrelation
is the leap into extrapolation.
Investigation –
prerequisition
for its condition
of affirmation –
remains vital for its validation.

Verification
through repetition,
beyond the point of exasperation,
and demonstration
will merit its serious admission
and acclamation.

Last comes the equation formulation.

[Jonathan Heather]

@john
1) Propose a hypothesis and write a bunch of maths.
2) Design experiment to test hypothesis, with a bunch more maths.
2a) Get loads of money from the government to test your maths.
3) Don't bother to develop a theory based on observational data, just make out it is a fact cos the maths 'proves' you can't be wrong despite any results to the contrary.
4) Build such an expensive bit of equipment they can't afford for you to be wrong.
5) And most importantly... NEVER ADMIT YOU ARE WRONG!
6) Even a proven theory is still a theory until a consensus
of scientist agree. But you can still find another way to spend gigabucks proving that you can't be wrong.

[jgfox]

The mistake they are making is that they are looking for "Dark Matter" when they should be looking for "Darker Matter".

That is much more difficult since it follows the Heisenberg uncertainy principal.

"the more precisely one property is measured, the less precisely the other can be controlled, determined, or known."

When you "look for it" ... it won't be there.

Only with the development of instruments which use "Darker Energy" will it be possible to detect and understand it.

But all bets are off, if it is really "Darkest Matter" that is the underlying principal.

[rvhalejr]

The only intelligent comments on this have come from you folks.
2.2 meter telescope measuring star movement amateur activity.
Adaptive Optics ?
Spectrometry ?
Interferometry ?
Notice how the pretty picture suggests cold dust and gas outside the galaxy, how could this have any effect on a solar body ?
Were they looking for interstellar material or inter galactic material ? There is some cogent info at rsta.royalsocietypublishing.org/content/368/1914/967.full
I doubt any instrument exists that can make a direct measurement
this close up (most dark matter observations are in deep space).
They need to find source producing a wavelength that is effected in some manner (frequency shift, low frequency beats, phase changes, IR thru Gamma, reflects, scatters, fluorescence, etc.) basically an indirect measurement, otherwise nada. Oh, as most of you know the US bailed on the space based Interferometer and a bunch of other programs until after 2025 or later. Perhaps the only way dark matter could be missing is described here spacedaily.com/reports/Cosmic_Leaf_Blower_Robs_Galaxy_of_Star_Making_Fuel_999.htmlThe new, high-precision map not only shows the
Galactic magnetic field's structure on large scales,
it also reveals small-scale features that help
scientists better understand turbulence in the
Galactic gas. sciencenewsline.com/space/2012020317190050.html so for now it seems to be about dust and gas which up close is going to be difficult to detect with out least modeling the sensitivity of the instrumentation with the expected particulate that is known to typically exist in such areas of space.

[Lubos]

There is no such thing as dark matter and the rotation of galaxies can be explained without the dark matter.
The thing is that the stars have radial velocity from center of galaxy outward, not inward. This is proven by many measurements. This is why the galaxies looks like the garden sprinkler and it is exactly how the stars move. It is clear to a child but the "scientists" just do not have common sense to accept this. There are of course many consequences like most of galaxies are about the same age which is around 500 milions of years, Our sun is just 375 milion years old (yes the Earth is older than the Sun).......

[wayne james]

lol this is so funny, (tesla & me to the rescue), you may find all the matter and energy in the universe is accountable if you have the correct calculation of gravity for a start, try this one G=(EA)M where E is the albido of a body, A is its surface area and M is the mass. there is no dark matter or energy out there, its made up bull to patch up the big bang crap they keep throwing out and curved space time? WTF..... tesla said straiten the lines, every action has a reaction, space curviture is not possible, if anything is missing witch i bet there still will be then you may want to factor into the equation the density of the medium of space (the ether as tesla called it) problem solved, next aha