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HERE IS THE STORY. A black activist commissioner in Dallas County was upset in a meeting by the use of the term "black hole." I called the Commissioners Court and asked for Commissioner Price. They connected me with his secretary, Melanie. We had a nice friendly conversation. It is not racist, and I am not afraid to say it, but her voice indicated that she was a black lady. MELANIE: Commissioner Wiley. DFU: Yes, ma'am, I'm Doug and I'm calling from California about the story of the black hole and Commissioner Wiley. M: Yes, sir. (sort of a little...

A team of Italian and Chinese physicists on Wednesday renewed a controversial claim that they had detected the mysterious dark matter particles that astronomers say swaddle the galaxies in halos and direct the evolution of the universe. The team, called Dama, from “DArk MAtter,” and led by Rita Bernabei of the University of Rome, has maintained since 2000 that a yearly modulation in the rate of flashes in a detector nearly a mile underneath the Gran Sasso mountain in Italy is the result of the Earth’s passage through a “wind” of dark matter particles as it goes around the Sun....

A detailed analysis of eight dwarf galaxies that orbit the Milky Way indicates that their orbital behaviour can be explained more accurately with Modified Newtonian Dynamics (MOND) than by the rival, but more widely accepted, theory of dark matter. The results were presented by Garry Angus, of the University of St Andrews, at the RAS National Astronomy Meeting in Belfast on Wednesday 2nd April. 'MOND was first suggested to account for things that we see in the distant universe. This is the first detailed study in which we've been able to test out the theory on something close to home....

PARIS (AFP) - An international team of astronomers peering into the deep Universe said on Thursday they had mapped the biggest-ever structure of the enigmatic substance known as dark matter. They detected a web of matter spanning 270 million light years, or more than 2,000 times the size of our own galaxy, the Milky Way, they said. Around a fifth of the Universe is believed to consist of dark matter, spreading out in mysterious filaments, sheets and clusters. But, with present technology, it cannot be seen directly. Its existence is perceived indirectly, through the gravitational pull it exerts on light....

DARK ENERGY DOMINATES THE UNIVERSE HANOVER, NH - A Dartmouth researcher is building a case for a "dark energy"-dominated universe. Dark energy, the mysterious energy with unusual anti-gravitational properties, has been the subject of great debate among cosmologists. Brian Chaboyer, Assistant Professor of Physics and Astronomy at Dartmouth, with his collaborator Lawrence Krauss, Professor of Physics and Astronomy at Case Western Reserve University, have reported their finding in the January 3, 2003, issue of Science. Combining their calculations of the ages of the oldest stars with measurements of the expansion rate and geometry of the universe lead them to conclude...

When a shot is fired, one expects to see a person with a gun. In the same way, whenever a giant star explodes, astronomers expect to see a galaxy of stars surrounding the site of the blast. This comes right out of basic astronomy, since almost all stars in our universe belong to galaxies. Image right: The robotic Palomar 60-inch telescope imaged the afterglow of GRB 070125 on January 26, 2007. Right: An image taken of the same field on February 16 with the 10-meter Keck I telescope reveals no trace of an afterglow, or a host galaxy. The white...

Einstein's self-proclaimed "biggest blunder" -- his postulation of a cosmological constant (a force that opposes gravity and keeps the universe from collapsing) -- may not be such a blunder after all, according to the research of an international team of scientists that includes two Texas A&M University researchers. The team is working on a project called ESSENCE that studies supernovae (exploding stars) to figure out if dark energy – the accelerating force of the universe – is consistent with Einstein’s cosmological constant. Texas A&M researchers Nicholas Suntzeff and Kevin Krisciunas are part of the project, which began in October of...

HAVE we hastened the demise of the universe by looking at it? That’s the startling question posed by a pair of physicists, who suggest that we may have accidentally nudged the universe closer to its death by observing dark energy, which is thought to be speeding up cosmic expansion. Lawrence Krauss of Case Western Reserve University in Cleveland, Ohio, and colleague James Dent suggest that by making this observation in 1998 we may have caused the universe to revert to a state similar to early in its history, when it was more likely to end. “Incredible as it seems, our...

Stays away from topic of financial market turmoil In a speech in Berlin on Tuesday, Bernanke did not address the current financial market turmoil or credit crunch. His comments stuck to the troubling issue of the large U.S. current account gap and corresponding surpluses in China and oil-exporting countries. Many economists and the International Monetary Fund have worried for years that there might be a sudden, sharp decline in foreign appetite for U.S. dollars, requiring higher U.S. interest rates to attract the necessary foreign capital to fund American's spendthrift ways. "What are the prospects for a gradual and orderly rebalancing...

Radiation was used to pinpoint the normal matter, while the observation of gravitational lensing was used locate dark matter. Gravitational lensing allows matter to be oberved, even when it does not emit or absorb light, by examining the movement of galaxies as our line of sight passes through the area of interest. Massive objects will distort the image and cause it to move in unexpected directions. Because the normal matter could interact through electromagnetic radiation, it was found to have slowed violently during the collision while the dark matter sailed on through... In the meantime, other astronomers began using gravitational...

The mysterious cosmic presence called dark energy, which is accelerating the expansion of the universe, might be lurking in hidden dimensions of space. The idea would explain how these dimensions remain stable - a big problem for the unified scheme of physics called string theory... quantum vibrations in the vacuum of space (called vacuum energy or the cosmological constant) that could produce repulsive gravity... should either possess a ridiculously high energy density - 122 orders of magnitude larger than are observed - or cancel out to exactly zero. To make them almost-but-not-quite cancel, in agreement with astronomical observations, means fudging...

An international team of astronomers have conclusive new evidence that a recently discovered "dark galaxy" is, in fact, an object the size of a galaxy, made entirely of dark matter. Although the object, named VIRGOHI21, has been observed since 2000, astronomers have been slowly ruling out every alternative explanation. In a new research paper, entitled 21-cm synthesis observations of VIRGOHI 21 – a possible dark galaxy in the Virgo Cluster, researchers provide updated evidence about this mysterious galaxy. They have now performed a high resolution observations of VIRGOHI21 using the Westerbork Synthesis Radio Telescope (WSRT), to better pin down the...

Astronomers have discovered an enormous, ghostly ring of dark matter 5 billion light years away — the most blatant evidence to date for the existence of a mysterious substance hidden throughout the universe. Dark matter makes up a vast majority of gravity-exerting mass in the universe, while only about 10 percent is matter we can see and touch. If dark matter didn't exist, scientists say, galaxies like the Milky Way would have already flown apart from a severe lack of gravitational "glue." Researchers pointed the aging but powerful Hubble Space Telescope toward a cluster of galaxies known as cluster...

...More than 100 scientists from across the globe are descending on McMaster University today... just 5 per cent of the universe is made up of matter we've long known about -- atoms, light, etc. The rest is mysterious dark matter (25 per cent) and the more recently discovered dark energy (70 per cent)... "For the first time in the history of man, it's possible to figure out the total energy in the universe, and the big news is that atoms are at most 5 per cent of what's out there," says Cliff Burgess, Mac professor of physics and astronomy, and...

Take one part unidentified goop. Add three parts mysterious energy. Throw in a dash of ordinary atoms. Mix. Compress. Explode. Let expand for 13.7 billion years. It's an absurd recipe, but it's one that makes cosmologists drool. Ten years ago, no one could agree on what the universe is made of, how it is shaped, or what its ultimate fate will be. But less than five years later, long-awaited measurements and one stunning discovery forever transformed our picture of the universe. The resulting model, often called the concordance model, holds that 22 percent of the universe is composed of dark...

The poster child for dark matter, which got a lot of attention last summer, is the Bullet Cluster of galaxies... What's less well known is that the smaller of the two colliding clusters is a cluster in a hurry, zipping along at 4700 kilometers per second... Farrar... and her graduate student Rachael Rosen estimated a few months ago that gravity should have accelerated the cluster to maybe 3000 km/s. Even if the cluster had an improbable combination of elongated shape, high initial velocity, and special viewing geometry, it should move no faster than 3400 km/s. Farrar concluded that some new...

Close window Published online: 7 January 2007; | doi:10.1038/news070101-7 Dark matter mappedFirst three-dimensional picture of elusive matter throws up mystery.Katharine Sanderson Concentrations of dark matter (mapped in contours above) usually - but not always - match up with normal matter (coloured). Hot on the heels of evidence last year that dark matter really does exist (see 'Dark matter spied in galactic collision'), the same technique has been used to map this uncharacterized mass across half a million distant galaxies. The map shows that, as predicted, the mysterious dark matter that makes up a quarter of the Universe forms a...

In the standard theory of gravity—general relativity—dark matter plays a vital role, explaining many observations that the standard theory cannot explain by itself. But for 70 years, cosmologists have never observed dark matter, and the lack of direct observation has created skepticism about what is really out there.Lately, some scientists have turned the question around, from “is dark matter correct?” to “is our standard theory of gravity correct?” Most recently, Fermilab scientists Scott Dodelson and former Brinson Fellow Michele Liguori demonstrated one of the first pieces of theoretical evidence that an alternative theory of gravity can explain the large scale...

After decades of intensive effort by both experimental and theoretical physicists worldwide, a tiny particle with no charge, a very low mass and a lifetime much shorter than a nanosecond, dubbed the "axion," has now been detected by the University at Buffalo physicist who first suggested its existence in a little-read paper as early as 1974. The finding caps nearly three decades of research both by Piyare Jain, Ph.D., UB professor emeritus in the Department of Physics and lead investigator on the research, who works independently -- an anomaly in the field -- and by large groups of well-funded physicists...

MOON DAILYBig Bang Afterglow Fails An Intergalactic Shadow Test Because it is seen coming from every direction in nearly uniform power and frequency, cosmologists theorized that the microwave background is afterglow radiation left over by the Big Bang that created the universe. by Staff Writers Huntsville AL (SPX) Sep 03, 2006 The apparent absence of shadows where shadows were expected to be is raising new questions about the faint glow of microwave radiation once hailed as proof that the universe was created by a "Big Bang." In a finding sure to cause controversy, scientists at The University of Alabama in...

When Douglas Clowe of the University of Arizona in Tucson announced on 21 August that his team had "direct proof of dark matter's existence", it seemed the issue had been settled. Now proponents of the so-called modified theories of gravity, who explain the motion of stars and galaxies without resorting to dark matter, have hit back and are suggesting that Clowe's team has jumped the gun. "One should not draw premature conclusions about the existence of dark matter without a careful analysis of alternative gravity theories," writes John Moffat, of the University of Waterloo in Ontario, Canada, who pioneered an...

A football player tackled hard enough may lose his helmet. Now, astronomers have found two clusters of galaxies that collided so hard one of them has lost its halo of dark matter, the mysterious invisible stuff that swaddles ordinary matter, according to measurements of the motions of stars and galaxies. In this picture, a composite based on observations with the Hubble Space Telescope, the Chandra X-Ray Observatory and other telescopes, the pink, bullet-shaped cloud of hot gas in a cluster speeding from left to right has been slowed and left behind by its dark matter, the blue blob to the...

BOSTON (Reuters) - A team of U.S. scientists has found the first direct evidence of the existence of "dark matter," a little-understood substance with a huge influence on gravity, the team's leader said on Tuesday. Scientists still do not know what exactly dark matter is, but have theorized it must exist to account for the amount of gravity needed to hold the universe together. They estimate that the substance accounts for 80 to 90 percent of the matter in the universe. The more familiar kind of matter, which can be seen and felt, makes up the rest. Now researchers led...

Everyone is scientific circles is abuzz with the big news: there's proof that dark matter exists! The paper from the scientists who made the discovered is here; and a Sean Carroll (no relation) has a very good explanation on his blog, Cosmic Variance. This discovery happens to work as a great example of just why good science needs good math. As I always say, one of the ways to recognize a crackpot theory in physics is by the lack of math. For an example, you can look at the electric universe folks. They have a theory, and they make predictions:...

Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter. "This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it...

NASA Announces Dark Matter DiscoveryAstronomers who used NASA's Chandra X-ray Observatory will host a media teleconference at 1 p.m. EDT Monday, Aug. 21, to announce how dark and normal matter have been forced apart in an extraordinarily energetic collision. Reporters must call Megan Watzke at the Chandra Press Office at: 617- 496-7998 or e-mail: mwatzke@cfa.harvard.edu for participation information. Shortly before the start of the briefing, images and graphics about the research will be posted at: http://chandra.harvard.edu/photo/2006/1e0657/Briefing participants: - Maxim Markevitch, astrophysicist, Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass. - Doug Clowe, postdoctoral fellow, University of Arizona, Tucson, Ariz. - Sean Carroll,...

How an alternate theory of the universe exposes the 'war of words' that underlies modern cosmology. Theoretical physicists have recently been frustrated by a bold hypothesis concerning black holes—specifically, that they don't exist. In March, at the 22nd Pacific Coast Gravity Meeting in Santa Barbara, Calif., George Chapline, an applied physicist at Lawrence Livermore National Laboratory, gave a talk based on ideas he's been incubating for several years. His goal: to amend astrophysics by applying theories of dark energy and condensed matter physics. His work reinvents black holes as so-called "dark energy stars," which are what is left over when...

Dark matter could be "sterile" neutrinos, whose decay led to the formation of stars in the early universe Dark matter may have played a major role in creating stars at the very beginnings of the universe. If that is the case, however, the dark matter must consist of particles called "sterile neutrinos". Peter Biermann of the Max Planck Institute for Radio Astronomy in Bonn, and Alexander Kusenko, of the University of California, Los Angeles, have shown that when sterile neutrinos decay, it speeds up the creation of molecular hydrogen. This process could have helped light up the first stars only...

Feb 28, 2006 In the Dark on Matter Fabulous Matter and Energy Since there is no experimental or observable evidence that dark matter exists, is it just a prop for the beleaguered big bang theory? This highly speculative construct is now combined with one just as fabulous--dark energy--to shore up current cosmological dogma.Credit NASA/CXC/M.Weiss Above: Chandra X-Ray Observatory estimates of the “total energy content of the Universe”. Only "normal matter” can be directly detected with telescopes. The rest of the matter and energy is invisible. In the 1930s, astronomers Fritz Zwicky and Sinclair Smith were puzzled by the motions they...

Three cosmic enigmas, one audacious answer 09 March 2006 Exclusive from New Scientist Print Edition Zeeya Merali DARK energy and dark matter, two of the greatest mysteries confronting physicists, may be two sides of the same coin. A new and as yet undiscovered kind of star could explain both phenomena and, in turn, remove black holes from the lexicon of cosmology. The audacious idea comes from George Chapline, a physicist at Lawrence Livermore National Laboratory in California, and Nobel laureate Robert Laughlin of Stanford University and their colleagues. Last week at the 22nd Pacific Coast Gravity Meeting in Santa Barbara,...

Once upon a time -- a bit more than 100 years ago -- many scientists believed that seemingly empty space wasn't empty at all, but was filled with a substance called luminous ether. This mysterious stuff, never seen in any laboratory on Earth, was thought to explain how gravity from one celestial body could affect another. By the end of the 19th century, though, luminous ether had gone the way of countless other scientific misconceptions. Today, another mysterious substance beguiles astronomers, and this one isn't going away. In fact, it's been at the forefront of cosmological theories for decades. It's ...

Painstaking observations of a kind of subatomic dance suggest that the universe may contain a shadowy form of matter that has never been seen directly and is unexplained by standard physics theories, a team of scientists working at Brookhaven National Laboratory on Long Island announced yesterday. The studies appear to confirm similar findings the scientists reported last year. The research involves muons, rare subatomic particles similar to electrons but 207 times as heavy. The work has been controversial, though for reasons that have little to do with the experiment itself. Theorists who are not involved in the research, but whose...

Reprinted from ScienceDaily Magazine ...Source:             NASA/Marshall Space Flight Center Date Posted:    Thursday, August 01, 2002Web Address:   http://www.sciencedaily.com/releases/2002/08/020801080835.htm Chandra Discovers "Rivers Of Gravity" That Define Cosmic Landscape NASA's Chandra X-ray Observatory has discovered part of an intergalactic web of hot gas and dark matter that contains most of the material in the universe. The hot gas, which appears to lie like a fog in channels carved by rivers of gravity, has been hidden from view since the time galaxies formed. "The Chandra observations, together with ultraviolet observations, are a major advance in our understanding of how the universe evolved over the last 10 billion...

Exclusive from New Scientist Hidden extra dimensions are causing measurements of the strength of gravity at different locations on Earth to be affected by the planet's magnetic field, French researchers say. This is a controversial claim because no one has ever provided experimental evidence to support either the existence of extra dimensions or any interaction between gravity and electromagnetism. But lab measurements of Newton's gravitational constant G suggest that both are real. Newton's constant, which describes the strength of the gravitational pull that bodies exert on each other, is the most poorly determined of the constants of nature. The two...

Quantum physics predicts the existence of an underlying sea of zero-point energy at every point in the universe. This is different from the cosmic microwave background and is also referred to as the electromagnetic quantum vacuum since it is the lowest state of otherwise empty space. This energy is so enormous that most physicists believe that even though zero-point energy seems to be an inescapable consequence of elementary quantum theory, it cannot be physically real, and so is subtracted away in calculations. A minority of physicists accept it as real energy which we cannot directly sense since it is the...

Extra Dimensions Showing Hints Of Scientific Revolution Chicago - Feb 19, 2003 The concept of extra dimensions, dismissed as nonsense even by one of its earliest proponents nearly nine decades ago, may soon help solve seemingly unrelated problems in particle physics, cosmology and gravitational physics, according to a panel of experts who spoke Feb. 15 at the American Association for the Advancement of Science annual meeting in Denver. "It doesn't happen often that you get a confluence of ideas and experiments that come together and it's something that obviously would change your whole way of looking at the universe,"...

Florida Physicist Says Dark Matter, Extra Dimensions Related And Possibly Detectable the universe is the "twilight zone" Gainesville -May 19, 2003 A team of scientists that includes a University of Florida physicist has suggested that two of the biggest mysteries in particle physics and astrophysics -- the existence of extra time and space dimensions and the composition of an invisible cosmic substance called dark matter -- may be connected. "For the most part, these two questions have been treated separately in the past, and for the first time we're making a direct link," said Konstantin Matchev, a UF assistant...

Thursday, 6 September, 2001, 10:39 GMT 11:39 UK Universe 'could condense into jelly' By BBC News Online's Helen Briggs The Universe may be in a state where matter could disintegrate at any moment, a scientist has warned. But the probability is less than that of buying two lottery tickets in the same week that both win the lottery, said Dr Benjamin Allanach of the European laboratory for particle physics, CERN, in Geneva. "The fact that the Universe has existed for 15 billion years should tell you it's not likely to happen tomorrow," he told the British Association Festival of Science ...

...The proposal bears an odd parallel to another modified-gravity theory that has emerged in recent years, and which seeks to explain another dark entity: "dark matter." Not unlike dark energy, dark matter is an unseen substance that astronomers believe pervades the cosmos, but it is different. Dark matter, which would comprise more than 90% of the weight of the universe, is thought to betray its existence through its gravitational pull on nearby objects. Somewhat similarly to what is happening with dark energy, some cosmologists have also devised modified-gravity theories in past years to explain these phenomena.

Physicists for decades have used "dark matter" as Spackle to fill pesky anomalies that seem to defy theories about gravity, the Big Bang and more. Recently, economists have proposed a similar fix for apparent anomalies in U.S. economic data. Unlike dark matter in space, dark matter in economics is a concept that has been mostly derided by other economists. If it's real, though, it might be no joke for investors. Harvard economists Ricardo Hausmann and Frederico Sturzenegger, [advance] a theory to explain something that has bugged economists and investors for years: A persistent trade deficit has built up a mountain...

Ricardo Hausmann Kennedy School of Government Center for International Development,, Harvard University Federico Sturzenegger Kennedy School of Government, Harvard University and Universidad Torcuato Di Tella November 13, 2005 Over the last couple of years the bludgeoning of the US current account deficit, currently ticking at over 700 billion dollars a year in 2005 alone, has led to significant concerns about the future of the US and the possibility of a major global crisis. It comes after 27 years of unbroken deficits which have totaled over 5 trillion dollars. Once the massive financing required to keep on paying for such a...

Alexander Franklin Mayer Theoretical Physicist and Cosmologist 1 February 2006 Welcome! For a number of months now at Stanford University (Physics), I have been quietly working on a book entitled The Many Directions of Time, which I anticipate will go to press in 2006. Here you will find a preview of related 'digital lectures' that have been created to appeal to a wide global audience including topic experts as well as students, amateur astronomers and scientific professionals of all varieties. The Introduction (17 PowerPoint slides) will take you less than 10 minutes to go through and should convince you that...

Clues revealed by the recently sharpened view of the Hubble Space Telescope have allowed astronomers to map the location of invisible "dark matter" in unprecedented detail in two very young galaxy clusters. A Johns Hopkins University-Space Telescope Science Institute team reports its findings in the December issue of Astrophysical Journal. (Other, less-detailed observations appeared in the January 2005 issue of that publication.) The team's results lend credence to the theory that the galaxies we can see form at the densest regions of "cosmic webs" of invisible dark matter, just as froth gathers on top of ocean waves, said study co-author...

Dark Matter: Invisible, Mysterious and Perhaps Nonexistent - By Robert Roy Britt Senior Science Writer 10 October 2005 Galaxies don't have enough regular matter to keep them from flying apart, scientists have been telling us for years. So there must be a bunch of unseen "dark matter" lurking in every galaxy. But dark matter has never been directly detected, and nobody knows what it might be made of. A few scientists remeain skeptical. To a lay person, it might sound downright crazy. Now a new study suggests there may be no such thing as dark matter. Fred Cooperstock of Northeastern...

Welcome to the fourth dimension. And the fifth, and the sixth. A team of astrophysicists claims to have identified evidence that space is six-dimensional. Joseph Silk of the University of Oxford, UK, and his co-workers say that these extra spatial dimensions can be inferred from the perplexing behaviour of dark matter. This mysterious stuff cannot be seen, but its presence in galaxies is betrayed by the gravitational tug that it exerts on visible stars. Silk and his colleagues looked at how dark matter behaves differently in small galaxies and large clusters of galaxies. In the smaller ones, dark matter seems...

A good description of the state of Dark Matter - perfect daytime TV.

Astronomers have discovered an invisible galaxy that could be the first of many that will help unravel one of the universe's greatest mysteries.The object appears to be made mostly of "dark matter," material of an unknown nature that can't be seen.    Images The ellipse shows the region of sky where the dark galaxy was found. Credit: Cardiff University/Isaac Newton Telescope on La Palma NGC 7479 is the type of galaxy astronomers would have expected to see based on the measurements taken. Credit: Nik Szymanek/Faulkes Telescope North, Maui, copyright FTLLC    More Stories Dark Matter Exposed: Animation Offers Clues to Cosmic Mystery...

An illustration of the inivisible galaxy The invisible galaxy could only be 'seen' using radio waves Astronomers say they have discovered an object that appears to be an invisible galaxy made almost entirely of dark matter. The team, led by Cardiff University, claimed it is the first to be detected. A dark galaxy is an area in the Universe containing a large amount of mass that rotates like a galaxy, but contains no stars. It was found 50 million light years away using radio telescopes in Cheshire and Puerto Rico. The unknown material that is thought to hold these...

Big bang sound waves explain galaxy clustering 13:32 12 January 2005 NewScientist.com news service Maggie McKee, San Diego Sound waves that roared through space after the big bang left behind a subtle imprint in the way galaxies are clustered today, reveal two major studies. The results bolster the standard theory that the universe is flat, and measuring the distance between the sound ripples may provide a new cosmic yardstick to probe the past. Two independent teams mapping the universe have found that galaxies are currently huddled together slightly more often at distances of 500 million light years as a...

Dark Matter Halo Puzzles Astronomers Summary - (Oct 26, 2004) Astronomers using the Chandra X-Ray Observatory have discovered a huge halo of dark matter around an isolated elliptical galaxy; an object that shouldn't have such a halo, according to optical observations. The galaxy, NGC 4555, is unusual that it's a large elliptical galaxy which isn't part of a larger cluster of galaxies. It's surrounded by a cloud of gas, twice the size of the galaxy itself, that's been heated to 10-million-degrees Celsius. This gas could only get that hot if it was being constrained by a halo of dark matter...