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Is Earth Weighed Down By Dark Matter?
Nerval's Lobster writes "There may be a giant ring of dark matter invisibly encircling the Earth, increasing its mass and pulling much harder on orbiting satellites than anything invisible should pull, according to preliminary research from a scientist specializing the physics of GPS signaling and satellite engineering. The dark-matter belt around the Earth could represent the beginning of a radically new understanding of how dark matter works and how it affects the human universe, or it could be something perfectly valid but less exciting despite having been written up by New Scientist and spreading to the rest of the geek universe on the basis of a single oral presentation of preliminary research at a meeting of the American Geophysical Union in December. The presentation came from telecom- and GPS satellite expert Ben Harris, an assistant professor of mechanical and aerospace engineering at the University of Texas- Arlington, who based his conclusion on nine months' worth of data that could indicate Earth's gravity was pulling harder on its ring of geostationary GPS satellites than the accepted mass of the Earth would normally allow. Since planets can't gain weight over the holidays like the rest of us, Harris' conclusion was that something else was adding to the mass and gravitational power of Earth – something that would have to be pretty massive but almost completely undetectable, which would sound crazy if predominant theories about the composition of the universe didn't assume 80 percent of it was made up of invisible dark matter. Harris calculated that the increase in gravity could have come from dark matter, but would have had to be an unexpectedly thick collection of it – one ringing the earth in a band 120 miles thick and 45,000 miles wide. Making elaborate claims in oral presentations, without nailing down all the variables that could keep a set of results from being twisted into something more interesting than the truth is a red flag for any scientific presentation, let alone one making audacious claims about the way dark matter behaves or weight of the Earth, according to an exasperated counterargument from Matthew R. Francis, who earned a Ph.D. in physics and astronomy from Rutgers in 2005, held visiting and assistant professorships at several Northeastern universities and whose science writing has appeared in Ars Technica, The New Yorker, Nautilus, BBC Future and others including his own science blog at Galileo's Pendulum."
Well considering the fact that even gravity is still not completely understood (yeah call me when you detect those gravity waves your theories predict), I wouldn't place any bets on the dark matter ring...
Seven puppies were harmed during the making of this post.
Clearly it's Red Matter.
"Any headline which ends in a question mark can be answered by the word no."
It's standard not to write all the technicalities down in a scientific presentation. They usually last 30 to 45 minutes. There is no way, even for a scientific mind, to follow all the technicalities in 45 minutes when it took several months for the speaker to grasp the subject. Nobody in the audience would understand anything aside from the coauthors. Imagine your 20 hours advanced graduate course on physics condensed in 45 minutes with no simplification at all.
Disclosure: I'm a mathematician, not a physicist.
Let's wait for the proceeding or the full paper even though it's true we should be skeptical at this point.
The excess mass is an invasion force of cloaked ships.
I thought we'd been using tiny variations in gravity to detect Oil for 20 or so years now, fly over an area and map the underground caverns based off gravity variation.
" one ringing the earth in a band 120 miles thick and 45,000 miles wide."
Presumably that would be outside the planet, and therefore would be counteracting the force of gravity towards the centre of the planet.
Or is there some other wierd geometry involved.
> geostationary GPS satellites
A what now?
this sounds like a new religion. watch out Scientology!
Gaia got married.
How was the accepted mass of earth measured? It should at least be consistent with large-scale behavior of our solar system. Now satellites see a harder pull from earth. The same pull should be seen from the sun. It would make sense to me if satellites saw a lower pull than sun, implying that some mass is at earth, but further out than the satellites. This way, not so much.
Is it drag induced by the outer parts (not perfectly vacuum) of the atmosphere?
Start burning some goats! God says fuck some burning goats or She'll stab you in the lungs!!
Could it be that dark matter is the sinister evil that is actually causing global warming, er, "Climate Change"?
Or perhaps dark matter is the hidden reason behind the sudden occurrences of autism?
Or cancer?
Or the poor economy?
Or UFO sightings?
Paranormal activity?
It's something you can see but we all seem to "know" it's there. Sure sounds pretty hokey to me.
It is also possible that this dark matter has a direct relation with the crime rate. Hmmm, This could explain my recent weight gain as well.
We would of had to know the precise mass and gravitational pull for any of the rockets or satellites we sent into space to work. Given that they have not all fallen back to earth, if their is any invisible matter out there, it is obviously in insignificant infinitesimally small amounts.
Troll is not a replacement for I disagree.
Yo mama!
A house divided against itself cannot stand.
Thanks for contributing nothing to the discussion.
You laugh at the power of Lord Cthulhu, the Great and Glorious One. You try to come up with "scientific" theories and fancy math but the truth will become apparent to you very soon.
Your screams of terror will be like the song of angels to me.
Dedicated Cthulhu Cultist since 4523 BC.
More information complexity creates more entropic potential energy.
http://en.wikipedia.org/wiki/Entropic_force
http://arxiv.org/abs/1207.4803
http://arxiv.org/abs/1001.0785
No, this research wasn't even published, it's a conference talk and a PR release. Go read the actual link, at the bottom of the long post, where Matthew Francis dishes it out. Here it is again in case you missed it:
http://galileospendulum.org/2014/01/02/no-dark-matter-is-not-messing-up-gps-measurements/
The later link from Dr Francis points out that the calculation has yet to be adjusted for the gravitational contributions of the Moon or Sun, and that it also doesn't make any relativistic corrections.
Those omissions puts the dark matter claim on par with "hey guys I haven't looked at it from far away but from right here it looks the Earth is pretty flat, yeah?"
And amazingly you managed to contribute even less. Must be pretty hard to come up with less than nothing.
Seven puppies were harmed during the making of this post.
The dark matter ring is merely a hypothesis. In my field (or science, engineering, or mathematics generally) we should follow the scientific method when reporting results at a meeting.
This guy was unfortunately presenting a hypothesis. He should have waited and tried to find more compelling evidence before presenting. New Scientist should be familiar enough with the scientific method to avoid publicizing a radical and unproven hypothesis.
Ha!
I'm a black guy and found that one quite clever.
A master of the art at work:
"Making elaborate claims in oral presentations, without nailing down all the variables that could keep a set of results from being twisted into something more interesting than the truth is a red flag for any scientific presentation, let alone one making audacious claims about the way dark matter behaves or weight of the Earth, according to an exasperated counterargument from Matthew R. Francis, who earned a Ph.D. in physics and astronomy from Rutgers in 2005, held visiting and assistant professorships at several Northeastern universities and whose science writing has appeared in Ars Technica, The New Yorker, Nautilus, BBC Future and others including his own science blog at Galileo's Pendulum."
"The human universe" - there's another one?
Do NOT burn the goats - they're much better medium rare.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
There was a lot of it weighing me down, but then one trip to the bathroom later and I feel much lighter!
My sig has no nature
The conclusions I read sounded like science fiction. I try very hard to get on-board and understand what is being explained, even for a layman like myself, I can usually wrap my head around a good portion of science on Slashdot. The claims being made come from a very small observation window, IMO. ...Sorry, that does not seem like enough time to develop anything resembling a reasonable scientific conclusion. For contrast, I got this from the tele watching Professor Andrea Ghez. Before she dared go on international media with her proof of objects orbiting a black hole, she collected 10+ years of data. She undoubtedly believed she was correct, well before the ten year mark, but, she waited, bided her time, and when she showed the orbit of these objects around the black hole, there was simply no argument against her proof. I wish more science was like that, but I understand the need for the theoretical side of it. This just reeks of sensational journalism, more than science. Also, keep in mind, we have the guy who "shot bigfoot" recently and is claiming proof... Oh, and that little war on evolution in our textbooks. *sigh*
Ha!
I'm a black guy and found that one quite clever.
Why do the words "bell curve" spring to mind?
I think it's a little premature to call a small difference in gravitational pull a by-product of "dark matter". We know so very little about the things we can actually see, measure, interact with and predict that this smells more like science fiction. Let's get an agreeable unified theory first and also a mathematical system which does not break down at scale. So much of what we know is hacked together out of assumption and week-kneed postulations that talk of dark matter is really little more than mental masturbation at this point.
Join the Slashcott! Feb 10 thru Feb 17!
Well, it sure looks bad for that research but it doesn't change that the blanket statement:
could only be made by someone unfamiliar with how scientific research work and who harbors an idealized vision of the scientist. Scientists are not infinitely intelligent, they have to specialize a lot (an a lot means specialized in a subfield of a field of a discipline), and most people in the audience won't be experts in the subject at hand and would be lost by the full technical details if they have only 30 minutes to assimilate them. This is reality, not TV where the resident scientist knows all physics, all maths, all biology and all of computer science.
The earth is getting lighter...
And Leon's getting laaaarger...
“He’s not deformed, he’s just drunk!”
I'm surprised no one has pointed out yet that this was exactly the behavior predicted by the Flying Spaghetti Monster pressing down on objects to keep them from floating into space.
I am officially gone from
This statement is inaccurate: "...predominant theories about the composition of the universe didn't assume 80 percent of it was made up of invisible dark matter" 80% of the universe is made up of with Dark Matter and Dark Energy. The theories suggests the universe is made up of about 27% dark matter (not 80%) which is the subject of the article. Dark energy is a sort of negative gravity and is the force pushing galaxies apart faster and not relevant to this article's topic. Dark energy makes up most of the energy mass of the universe at 68%. Taken together they make up 80%, but affect the universe in completely different ways. http://en.wikipedia.org/wiki/Dark_energy
That is a ponderous paragraph for the Slashdot headlines. Your prose needs a diet. How about a synopsis first?
Allah dat dark stuff gots to be sumwhere!
"Sir, I think there's a problem with our calculations."
"Uh... uh... dark matter! Yeah, that's the ticket!"
That "sentence" is a crime against humanity. Also, it kicked my dog.
There you go.
They're only considering dark matter and dark energy, what about dark space and dark time?
planets can't gain weight over the holidays like the rest of us
Actually they do. It's estimated that the Earth gains at least 164,000 kg per day from meteoric accretion. (Barker, J.L. and Anders, E. "Accretion rate of cosmic matter from iridium and osmium contents of deep-sea sediments." Geochimica et Cosmochimica Acta 32, 627-645 (1968))
You never really know how close to the edge you can go until you fall off.
Dark Matter something that is completely undetectable by all known scientific instruments, yet it's something that a bunch of people believe that exists because some papers postulate its existence and it conveniently explains away the holes of knowledge in their current understanding of the world. H'mm. That concept seems vaguely familiar.
Dark matter has evolved from being simply being a concept to describe a deficiency in current scientific theories to something that actually exists in the physical materialistic realm.
80% of the universe is made up of with Dark Matter and Dark Energy. The theories suggests the universe is made up of about 27% dark matter (not 80%) which is the subject of the article. Dark energy is a sort of negative gravity and is the force pushing galaxies apart faster and not relevant to this article's topic.
The whole notion of "dark matter/energy" seems a little desperate to me. We have evidence that our models of gravity cannot account for certain observations. That means one of two things. Either A) the model is correct and there is something out there that has mass that we cannot presently see OR B) the we can see all the matter out there meaning the model is wrong and needs revision. So far I've seen no compelling argument that A is more likely than B. I understand the hesitation to revise our model of gravity but invoking dark matter/energy is an awfully big fudge factor in the absence of any plausible explanation for what might constitute dark matter/energy.
If we were to go to another habitable planet that wasn't circled by dark matter, we'd be able to fly, and steel projectiles traveling at supersonic speeds won't be able to penetrate our skin and clothing?
Subject != headline.
There YOU go.
There are two types of people in the world: Those who crave closure
27 + 68 = 95. Our physical laws don't predict about 95% of the universe.
Since dark matter doesn't interact with itself and with normal matter why doesn't always collapse on itself and form mini black holes?
A microscopic black hole recently produced by the LHC has moved to center
of the Earth and is exponentially growing and consuming all matter, leading to
an increasing effect on the Earth gravity field.
I read this several years ago.
Modified Lorentz Ether Gauge Theory
The mainstream authorities are fond of saying that GPS would not work if it weren’t for Einstein’s relativity. Clifford Will of Washington University has been quoted31 as saying:
SR has been confirmed by experiment so many times that it borders on crackpot to say there is something wrong with it. Experiments have been done to test SR explicitly. The world’s particle accelerators would not work if SR wasn’t in effect. The global positioning system would not work if special relativity didn’t work the way we thought it did.
Oh really? What does one of the world’s foremost experts on GPS have to say about relativity theory and the Global Positioning System? Ronald R. Hatch is the Director of Navigation Systems at NavCom Technology and a former president of the Institute of Navigation. As he describes in his article for this issue (p. 25, IE #59), GPS simply contradicts Einstein’s theory of relativity. His Modified Lorentz Ether Gauge Theory (MLET) has been proposed32 as an alternative to Einstein’s relativity. It agrees at first order with relativity but corrects for certain astronomical anomalies not explained by relativity theory. (Also see IE #39, p. 14.)
It's Nibbler.And the Niblonians...
I work with GPS a lot, and there are many MANY people around the world who spend their entire lives making sure that there are very precise measurements of where those satellites are and how good predictions of where they'll be going are. These orbit calculations take into account the pressure of light from the sun on the satellites along with several other very small effects, so if there was some large extra mass in a ring around the earth it would have been noticed many years ago. I think this guy needs to recheck his calculations.
Dark matter ring? It couldn't be anything more mundane, like minute variations in gravity pulling satellites further than the average gravity should, or the solar wind's effect being misinterpreted as gravitational pull?
From New Scientist :
That, alone, would make this fail peer review, not to mention that the GPS satellites (which are big and messy and do stationkeeping and get replaced) are not the satellites to use to do this with (the Lageos satellites fit both requirements, being both well monitored and with very low non-gravitational perturbations). The Lageos orbit at a lower altitude than GPS, and so would be expected to exhibit a greater difference with the orbit of the Moon (the other very stable and well characterized Earth orbiter, thanks to Lunar Laser Ranging).
Back in 2008, Adler compared Lageos and LLR estimates of Earth gravity in http://arxiv.org/pdf/0808.0899.pdf and concluded that Earth bound dark matter (outside of the 12,000 km semi major axis of Lageos) is 4 x 10^-9 Earth masses, much below Harris's 5 x 10^-5 estimate (which is based on a comparison with an ancient IAU determination from the 1960's). Given the poor analysis and the discrepancy with the more accurate data used by Adler, I do not think that these results can be given any credence.
So I'm not really getting fat. I just have a ring of dark matter around my midsection that looks like fat. My weight gain is actually a physics experiment.
Not completely. We can detect it gravitationally and it has upper and lower bounds constraining its properties and abundance. That's still infinitely better than any religion had done. Additionally if we find conclusive evidence that contradicts the theory of dark matter we are happy to discard it in favor of a theory that fits the evidence more accurately.
I don't trust this whole "theory of gravity." Obviously, this "theory" is just an unknowable guess and therefore doesn't have the full consensus of "science". I say we need to teach the controversy that the reason we stay on the earth is because some supreme being wants us there. Birds and planes only work because when their wings are outstretched they make a holy cross.
Teach the controversy. Don't believe "theories".
Slow Down Cowboy! It's been 1 hour, 47 minutes since you last successfully posted a comment
With all this talk of burning and cooking goats will someone please think of the poor goat fuckers
I wish I could have just written "Dark Matter" as the answer every time my math homework didn't add up to the correct number due to math errors. Obviously nobody knows precisely how much the Earth weighs...or the entire universe. In fact, how are they counting stars' mass from 10 million light years away by viewing 10 million year out of date light from it? And how are they counting mass that's already inside black holes from a not so viewer friendly distance away? Dark Matter is a myth.
Honey bunches of goats is good for breakfast.
rewriting history since 2109
is where I stopped reading.
No one has ever come up with a theory of Modified Gravity that can explain the data we have , but Dark Matter does.
Never mind the tiny, little, minor detail that we have NO idea if dark matter actually exists or what it might be composed of it it does exist. It's not an unreasonable theory to investigate but I'm pretty reluctant to invoke some new exotic form of matter as a go-to explanation. Remember it was 400 years between Newton and Einstein. If the math model needs adjusting (and dark matter turns out to not be the answer) it might be a while before we figure it out.
And dark matter makes up 84% of the matter in the universe (27/(27+5) = 0.84375), which is the 80% the article is talking about.
Like, I dunno, maybe dark matter?
Maybe but the point you ignored is maybe-not. With the evidence in hand, an incorrect model is a much cleaner explanation than some as yet undiscovered exotic form of matter than we aren't actually sure exists. I'm not saying dark matter doesn't exist, merely that I'm skeptical in light of the lack of evidence. It sounds like an effort to make the data fit the current model when there is a non-trivial chance the current model is wrong somehow.
I say we need to teach the controversy that the reason we stay on the earth is because some supreme being wants us there. Birds and planes only work because when their wings are outstretched they make a holy cross.
OK, then, explain balloons and the Flying Wing aircraft! Clearly your cross-based supreme being is a fraud, and the FSM is the One True Being (not to be confused with the molpy-laden One True Thread, but I digress even deeper into metasarcasm).
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
Isn't the whole point of DM that we can't detect it except by the gravity distortion? Its basically "unfound matter"...
And what means is what we really have is a distortion of gravity in a given area that we cannot count for... its therefore not dark matter but dark gravity.
Or am I wrong? have we actually found dark matter? The actual stuff. Proven to exist? Or is it just what we write down when our math doesn't add up?
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
"ring of geostationary GPS satellites". No. GPS satellites are not geostationary.
C'mon, don't reinvent the wheel here. The theory of Intelligent Falling is the go-to parody, and is well-known enough to have a Wikipedia page. You might also find last-Thursdayism amusing.
Socialism: a lie told by totalitarians and believed by fools.
If the headline is a question the en answer is almost certainly "No", and the reporter unqualified for the topic.
kartune85 : Incapable of reason, observation or learning. A kind of dim, drab, flightless parrot.
Dark matter..remembers me of ether.
The Moon and Sun would act to counter earths gravity, making it appear lighter not heavier.
Remember when we smashed a Mars Lander because we converted wrong?
Maybe dark matter is just somebody making a similar conversion error.
-- Tigger warning: This post may contain tiggers! --
Wait, so there are only gravity waves and capillary waves in water?
How do you get water to ignore light waves? Is it dark underwater where you lives?
-- Tigger warning: This post may contain tiggers! --
Surely they mean mass. The earth is in freefall (orbit) around the sun, hence it has a weight of 0!
The earth getting heavier is my fault. I need to ease up on the McRibs.
It already explains that this matter exists, and is even used by humans: as packing peanuts.
I would bet it just has to do with all of the energy and mass from all the other satellites orbiting the earth ..while in the past space has been filled with very few small things(because they get pulled into and around bigger things..) the earth is filled with new satellites and other orbiting matter created an set into orbit by man ..since few people have taken the time to build a holistic equation to cover everything go around the earth its unlikely the data has been plotted..the sad news is when its figured out it likely won't be news...
This means that the next time I visit my doctor and he mentions my weight, I can say; "Doc, it's that gawd-danged dark matter, it hangs around me like a cloud"!!!
My karma is bad. Don't get too close!!!