The dark matter in the Milky Way is not behaving as its supposed to
The uncertainty of science: Scientists using precise data of the motions of the outer stars of the Milky Way from the Gaia orbiting telescope have found they do not rotate the galaxy’s center as fast as expected, based on the theory of the existence of dark matter.
Dark matter was proposed to explain why in other galaxies the speed of rotation of outer stars does not appear to decline with distance (as seen for example with the planets in our solar system) but remains the same, no matter how far out you go. That extra speed suggests there must be unseen matter pulling on the stars.
[N]ew results that combine Gaia measurements with those from APOGEE (Apache Point Observatory Galactic Evolution Experiment), performed on a ground-based telescope in New Mexico, USA, and which measures the physical properties of stars to better judge their distance, have indeed measured the Milky Way’s rotation curve for stars out farther than ever before, to about 100,000 light years. “What we were really surprised to see was that this curve remained flat, flat, flat out to a certain distance, and then it started tanking,” says Lina Necib, who is an assistant professor of physics at MIT, said in a statement. “This means the outer stars are rotating a little slower than expected, which is a very surprising result.”
…The decline in orbital velocity at these distances implies that there is less dark matter in the center of our galaxy than expected. The research team describe the galaxy’s halo of dark matter as having been “cored,” somewhat like an apple. The crew also says there’s not enough gravity from what dark matter there seems to exist there, to reach all the way out to 100,000 light years and keep stars moving at the same velocity.
The rotation data of other galaxies, while somewhat robust, also includes a number of assumptions might be fooling us into thinking that the speeds are higher than expected. The more precise data gathered nearby, in the Milky Way, is now suggesting those assumptions and that distant data must be questioned.
Or to put it more bluntly, dark matter remains an ad hoc solution to a mystery that astronomers really don’t understand, or have sufficient data to explain. It might very well be a wild goose chase that has made them miss the real answer, whatever that might be.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The uncertainty of science: Scientists using precise data of the motions of the outer stars of the Milky Way from the Gaia orbiting telescope have found they do not rotate the galaxy’s center as fast as expected, based on the theory of the existence of dark matter.
Dark matter was proposed to explain why in other galaxies the speed of rotation of outer stars does not appear to decline with distance (as seen for example with the planets in our solar system) but remains the same, no matter how far out you go. That extra speed suggests there must be unseen matter pulling on the stars.
[N]ew results that combine Gaia measurements with those from APOGEE (Apache Point Observatory Galactic Evolution Experiment), performed on a ground-based telescope in New Mexico, USA, and which measures the physical properties of stars to better judge their distance, have indeed measured the Milky Way’s rotation curve for stars out farther than ever before, to about 100,000 light years. “What we were really surprised to see was that this curve remained flat, flat, flat out to a certain distance, and then it started tanking,” says Lina Necib, who is an assistant professor of physics at MIT, said in a statement. “This means the outer stars are rotating a little slower than expected, which is a very surprising result.”
…The decline in orbital velocity at these distances implies that there is less dark matter in the center of our galaxy than expected. The research team describe the galaxy’s halo of dark matter as having been “cored,” somewhat like an apple. The crew also says there’s not enough gravity from what dark matter there seems to exist there, to reach all the way out to 100,000 light years and keep stars moving at the same velocity.
The rotation data of other galaxies, while somewhat robust, also includes a number of assumptions might be fooling us into thinking that the speeds are higher than expected. The more precise data gathered nearby, in the Milky Way, is now suggesting those assumptions and that distant data must be questioned.
Or to put it more bluntly, dark matter remains an ad hoc solution to a mystery that astronomers really don’t understand, or have sufficient data to explain. It might very well be a wild goose chase that has made them miss the real answer, whatever that might be.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The thing that gets me with dark matter (dark energy, too, for that matter) is that I am reminded of relatvistic kinetic energy. Everybody knows the Newtonian equation, and the Einsteinian version ‘just’ adds an addendum that, at low velocities (as compared to c) reduces to zero, but at high velocities dominates.
And with this example, the obvious solution is… invent an otherwise undetectable substance(s) that outmasses the visible universe. Let’s just say ‘dark matter’ seems an inelegant solution and it reeks of inventing fudge factors so the numbers turn out right… especially when I’m staring at a failed prediction.
What’s really worrisome is the idea that someone will come up with a more complete gravity equation and it’ll be rejected because its model won’t work if you include dark matter.
Add in weirdness like last year’s discovery of galaxies older than was supposed to be possible, and you really start wondering about the folks trying to explain the larger, more distant parts of the universe.
How do they calculate the gravity of a galaxy? All coming from the center or do they use a gradient that reduces as it gets closer to the edge,
As I once said to Bob in an interview, I call these “placeholder theories” that are used to try and explain what we don’t understand or have enough data to truly study. That is fine except such placeholders then get taught as being something more than what what they are.
Robert Pratt wrote: “That is fine except such placeholders then get taught as being something more than what what they are.”
The Ether (i.e. aether) was a similar placeholder. At the time, it was believed that light waves must travel through a medium, like every other wave we know about, so Aether was invented to explain how light worked. Quantum mechanics changed that way of thinking, and aether disappeared in a puff of physics — a new branch of physics.
The Strong Force and the Weak Force work on nanoscopic scales, scales where gravity is too weak to have noticeable effects. Perhaps dark matter and dark energy similarly are as-yet unknown forces that are only observable in the scale of the vastness of the universe. There may be no dark matters or dark energies to find, just unknown forces.
Or maybe dark energy is a result of misinterpretations in our theories, and maybe dark energy has similar roots in misinterpreted data. As Robert Zimmerman says, “The uncertainty of science.”
If we knew all the answers, we wouldn’t need science.
And this could all be a misinterpretation of gravity and its effects.
Just a fraction off and it could change things significantly.
MOND for the win
Paul Steinhardt –
Time to Take the ‘Big Bang’ out of the Big Bang Theory? (May 5, 2021)
https://youtu.be/S7-HNi2ne44
(54:45)
It would be helpful if everyone used the same terminology/models. Newtonianly (is too a word), gravity is a force/acceleration that bends straight lines. Einsteinianly, it is the curvature of space and all non-accelerating (gravity is NOT such a thing) lines are straight.
The “orbiting too fast” problem looks vastly different from those two perspectives. In Newton-land, the force is unexpectedly strong. In Einstein-land, space is unexpectedly too curved. An “obvious” answer to the latter: Something besides mass can bend space. You can’t even say that in Newtonian terms.
BTW: This is a great animation: https://www.youtube.com/watch?v=wrwgIjBUYVc
yes the unexpected Keplerian decline detected in the MW by GRACE was in the news earlier
suspect lambdaCDM is going to be on life support after the Euclid data sharply refines the possible values for both dark energy and dark matter across a much wider slice of the observable universe
timescape theory and primordial black holes/remnants may do away with dark energy and matter respectively by the end of 2025
the final victories of the Standard Model
indeed timescape theory by itself might contribute to both — if time is running slightly faster in voids, that might exaggerate the rotational speeds we observe in other galaxies, leading to the false conclusion they must have more dark matter than is actually the case
While I’m fascinated by astronomy, I’m not a professional astronomer or physicist. But I can’t help but wonder that when you’re trying to measure things that are millions or billions of light years away, how can you be sure that no outside force has affected the light on its journey to Earth.
TexTaz, your assumption is correct.
There’s a small amount of matter between galaxies, mostly hydrogen and helium, but enough that most of the light (shorter wavelengths) is filtered out by collisions over vast distances. (it can be argued that the small amount of that energy is part of the universes background energy/radiation signature and imparts an electrical charge to the interstellar gases)
The further away an object, the more red it becomes. (A secondary explanation for “red shift” not involving speed, Just “filtered” light leaving the appearance of a red object)
That’s why the new infrared telescope is so successful, although the red spectrum is not very powerful, it has the ability to pass around interstellar gas allowing us to see through with better detail of what’s out there behind the dust, behind the black. With every new picture, we are seeing things that we had no clue that was there.
As for dark matter, if I can’t see it, taste it, touch it or analyze it… it’s not in the realm of science and should be left to the mediums, dowsers, palm reader‘s, remote viewers, and witch doctors. The unseen world of ghosts, angels/ demons, trans dimensional is their domain and has a great usefulness as entertainment… Not science. More rational explanations should be applied before grasping the ideas of our “invisible” darker natures.
Flat spiral galaxies spin like a record, all stars from the center bulge to the outer reaches are moving as if “static”, at the same speed. Obviously, gravitational orbital mechanics do not apply. (except inside the gravity well of star systems such as binaries, and planets)
A different model must be referenced based upon observation.
stars are too distant from each other for gravitational influence, even black holes, as massive as they are, can only influence within a few light-years. (The inverse squared of the distance sort of stuff)
Although the spiral arms of the galaxy are obviously attracted too, and rotate around each other. Also are usually symmetrical with the other side of the galaxy indicating a gravity balance even over great distances. This becomes obvious as smaller galaxies are attracted and pulled in to collide with bigger galaxies (which defies the expanding universe model) that has a whiplash affect throwing stars caught ”in between” into deep space which means the balance is “delicate”, it only appears to be secure.
I prefer the hurricane model.
Clouds of gas swirling and condensing, not because of gravity, but magnetism from static electrical currents attracting dust and gas into galaxies of individual stars, but maintaining there angular velocity relative to their original position in the cloud. (magnetism is a stronger force than gravity, but it’s influence is “limited” by the same laws of distance)
I do not know what I do not know, is it quantum entanglement that holds the galaxy together? Or Zero point energy?(All atoms vibrate continuously forever without entropy… how?) String theory? Or is it like the weird way low tide drops below sea level at 90° to the above sea level high tide due to strong gravitational influence? Or a sub space worm holes linking all gravity wells together? (like a chain of ice skaters pivoting around the center, and when the center it’s a little quicker… The outer skaters bend inward wrapping around the center like spiral alarms)
I do know that invisible dark mass only complicates the explanation, without coming close to solving it. Those with more imagination then problem-solving abilities will take advantage of the science community… Not because they have answers but because they can fool others with complicated explanations that has the form of science but no empirical data. The better you are at fooling others, the more successful you become. (how many billions is spent on global warming with no effect?… destroying economies with no evidence “ever” of a greenhouse event has ever been measured!)
Oh there’s a thought, is greenhouse theory and dark matter related? No evidence for either one. But that doesn’t stop people from being deathly afraid of the unseen monster in the closet… imagined fears are powerful motivations.
Max wrote: “I prefer the hurricane model.
“Clouds of gas swirling and condensing, not because of gravity, but magnetism from static electrical currents attracting dust and gas into galaxies of individual stars, but maintaining there angular velocity relative to their original position in the cloud. (magnetism is a stronger force than gravity, but it’s influence is ‘limited’ by the same laws of distance)”
What if the effect we see is not dark matter at all but an effect caused by an imbalance of electrical charge within galaxies? Could the lighter electrons be emitted more easily from solar systems than the heavier ions they came from? Perhaps solar systems slowly gain a positive charge and the space between stars slowly gains negative charge. Perhaps such an imbalance causes an effect similar to dark matter, on the way stars orbit in the arms of spiral galaxies. It may be a complicated calculation to explain how this electrical charge distribution would cause the effect we see, but could it be the cause?
“Those with more imagination then problem-solving abilities will take advantage of the science community… Not because they have answers but because they can fool others with complicated explanations that has the form of science but no empirical data. The better you are at fooling others, the more successful you become.”
Oh, look at that. Max caught me. I guess I won’t become very successful.
I’ll drop this in here:
Brian Keating Podcast (Jan 19, 2024)
Stephen Wolfram
https://youtu.be/c-RO3vM10Ok?t=2719
–cued to the relevant part, wherein Wolfram describes dark matter as the “caloric” of our day.
(Personally– I think there’s something with our observations. Way too many people are all-in on this thing’.)
Wayne, I had to laugh. I know this guy is way smart and at the top of his game… while listening to him, I reminded of an old saying “that if you can’t dazzle them with your brilliance… Baffle them with your [deleted]”
Using egg head terminology instead of words that communicate meaning causes the audience to lose the point that he’s trying to make. It’s like trying to understand a Catholic priest or a Doctor who insist on talking in Latin to describe particular items in the original language to be technically correct, and yet nobody understands what the heck they’re saying.
The dark matter discussion was very interesting in that he admitted he doesn’t know what it is, but he suspects it’s quantum or subatomic particles in the vacuum of space that gives gravitational dimensions to vacuum.
That means empty space will warp space-time like a gravitational body… Picture the bowling ball on a sheet of rubber with the marbles circling it to indicate the bending of space… And he’s theorizing this is occurring in empty space with no mass to bend it? Wouldn’t light from distant galaxies be bent and curved all over the place? Would intergalactic space have so much gravity that would pull galaxies apart?
I could go on and on about the consequences which is not evident in the observations. Occam‘s razor is the sensible solution to most problems. It seems the combined gravity of billions of stars has an influence. Stars outside this influence is unaffected until they come to close as we see in galaxies colliding.
In these cases we can see the stars on the outside of each galaxy being pulled towards each other elongating both galaxies… And in the ones who brush by each other, the galaxies change course and become caught in a gravity well being pulled in closer, while the outer stars are flung in to deep space. Do you see any influence of dark matter, mass 90% greater than the visible stars? Neither do they, but the grant money says they have to find it or make it’s non existence less plausible to politicians.
Edward;
You may have something there, it definitely has affect on clusters of gas as we see in supernovas in the bow shock.
Jupiter is a good example of a magnetic field created by an electrical field in/from its atmosphere. Caused by Jupiter being nearly 4 times hotter than the sun. With the great red spot being a south pole melting the moon Io with every passing. (electrical/magnetic induction) Jupiters gravity is great, but it’s magnetic field is greater!
Interstellar gases and nebula gases are extremely hot… How? Your electrical hypothesis may not be far wrong.
What would happen if interstellar gas from A supernova in the local chimney was conductive? What would happen? Would the sun’s electrical potential discharge from the sun throughout the ionizing gas cloud into the surrounding planets? What would be the consequences?
Interesting thought experiment. Expand and add some fancy Latin technical terms and you’ll be very successful.
I just remembered a theory by a professor from my college days in the early 80s. He hypothesized if gravity was a constant wave front extending out from stars, then wouldn’t those waves overlap each other in the vacuum of space? The way ripples from heavy rocks thrown in a pond grow larger when the ripples hit each other? Could this gravity concentration interact and create a black hole? Or at the very least, great contractual voids that suck in matter creating new stars?
Keep in mind this was before I learned of the proof that gravity is a force, like magnetism, not a particle or quantum material affected by the constant (speed of light).
When I think about it, the fictional gravity waves coming from different directions will pull each other apart, not combined to become greater. Just as magnets do not create a separate interactive magnetic field in the void between them.
This is where I usually tell a story of my friend who worked at JPL making instruments. How they developed a more sensitive gravity detector.
They were testing it, pointing it at the moon and it worked perfectly, but when they pointed it at the sun… it would point off-center where the sun will be in about eight minutes…. proving gravity is instantaneous like magnetism, and does not travel at the speed of light.
Max: I have deleted the very clearly implied obscenity from your post. You are warned very seriously. If you do it again I will suspend you.
What is with everyone these days that no one can write two sentences without inserting foul language for no reason? Does no one any longer wish to be a civilized person? Are you all trying to be the barbarians and savages who are trying so hard right now to destroy our civilization?
I set these rules for many reasons, with the first being I want this site above all to be a haven for civilized behavior. If you can’t maintain that standard then go elsewhere.
I also think that in the future, I will not simply delete the obscenity or the implied one, but I will delete the entire comment. Think about it. You spend a lot of time writing something, and you will have it vanish into the ether because you nonchalantly thought I don’t mean it when I set some simply rules of civility on my website.
This now applies to everyone. Be aware. I am tired of saying this over and over again.