Dark Matter Signal?

Does dark matter have a signal?  One that can be identified and traced?  Most astrophysicists would say no.  However odd "signals" emanate from the galaxy's center every now and again. 

From the ARTICLE

• Scientists analyzing high-energy gamma rays emanating from the galaxy's center found an unexplained source of emission that they say is "consistent with some forms of dark matter."  

What makes the task difficult is that scientists do not even know what dark matter is made of.   But theoretically, if dark matter were made up of something called Weakly Interacting Massive Particles this material  could possibly produce gamma rays in ranges that Fermi could detect. 

These signals are far from convincing 

Is Our Understanding of Gravity Fundamentally Wrong?

At a recent RAS National Astronomy Meeting, a team of astronomers headed by Hongsheng Zhao presented a radical paper on our understanding of gravity. First their theory suggests that the Milky Way and Andromeda collided 10 billion years ago and this would mean that our understanding of gravity is fundamentally wrong. However it would go a long way towards explaining the observed structure of the two galaxies.

In 2009, Zhao led An international team of astronomers that found a strange link between 'dark matter' and galaxies that suggests unknown force is acting on dark matter.

Zhao's research suggests that the interactions between dark and ordinary matter could be more important and more complex than previously thought, and even speculate that dark matter might not exist and that the anomalous motions of stars in galaxies are due to a modification of gravity on extragalactic scales.

 

The rest of the Daily Galaxy Article is Great, check it out HERE

Could This Be Where Some of the Universe's Missing Mass is?

Oh and the first person that calls the show Saturday and says...what? You reach into your back pocket?!" gets hung up on! lol Ok, here is what I am basing this question on. Astronomers used to think that elliptical galaxies contained around a trillion stars each. But looking at new data, they believe that these types of galaxies actually contain five trillion to ten trillion stars, and that by itself means the universe would have three times as many stars as we'd previously believed.

The new data come from technological advancements in detecting much dimmer stars or red dwarfs. Up until recently, red dwarf stars have been extremely difficult to detect because they are extremely dim in nature. Now that astronomers can detect the red dwarfs it turns out red dwarfs are way more common than was previously believed. Elliptical galaxies contain around 20 times as many of them as our own galaxy and could turn out to make up 80 percent of all stars in the universe. This could mean there's less "dark matter" than previously thought, since these red dwarfs could account for a lot of the universe's missing mass.

IO9 red dwarf article Wiki Red Dwarf article
Thanks to Dan for bringing the article to my attention

What is the Difference Between Dark Matter & Dark Energy?

Now there is the 10 thousand dollar question of the day... ain't it. I will admit to being confused by the difference myself. That is what made this article in The Daily Galaxy so very interesting.

As it sits right now, Only 4% of the stuff that makes up the universe is stuff we understand. So what is the other 96%? Well two names keep coming up and what confuses me is the fact that even learnered people use the two labels interchangeably - dark matter and dark energy.

From the article:

• ...astronomers at the University of St Andrews are attempting to “simplify the dark side of the universe”. They say the two most mysterious constituents in the universe are actually the same thing.

Hummm somehow that doesn't seem to clear anything up - but it would seem dark matter and its counterpart dark energy are so closely intertwined that it’s not clear that they’re even two different materials, but instead, two sides so to speak of the same coin.

What really makes the whole argument strange is the 4% we see might in fact be all the matter that there is in the universe. Some scientists say that many of the new findings may instead point to a reinterpretation of the dark component as a modification of the law of gravity rather than particles or energy.

That clear things up for you? No?

Read the complete Daily Galaxy article. It really is indepth and has a wealth of solid information.

Evidence that Dark Matter formed Galaxies

Here is an interesting short video I found on The Daily Galaxy blog that has Ian Morrison speaking at Gresham College in London - November of 2008. Morrison speaks on evidence that seems to indicate that dark matter began accumulating shortly after the big bang and ultimately allowed normal matter to draw together and for the galaxies as we see them today.

Physicists Find Dark Matter?

In a recent Wired article I read about a new experiment may have found the first direct evidence of dark matter particles. Theorists believe that dark matter, made up of of weakly-interacting massive particles, composes 23 percent of the universe, but no one has ever directly detected one of these WIMPs. Now, physicists have announced they've spotted electrons with just about the amount of energy they would have expected to be made by a particular kind of WIMP. John Wefel of Louisiana State University and colleagues report in Nature Wednesday that they could have detected "Kaluza-Klein" electron-positron pairs resulting from the annihilation of these WIMPS.

<-read complete article in Wired->

Is the Planet Trapped in a Space-Time Bubble?

Here is a story that has science fiction written all over it. The question: Is the Planet Trapped in a Space-Time Bubble? Now how, are you asking, did we arrive at THAT bizarre conclusion? Let me explain. In a recent article published in the Daily Galaxy the argument was made for some of the odd actions that far off galaxies and other object exhibit. Really far off object seem to be expanding away from Earth. Every far off object, no matter what direction you look in is moving away. Forever expanding. Weider still they ALL are accelerating. Now most astronomers almost to a person will put forth that there is an unseen force and "dark matter" that is between every galaxy and there for producing a force that is pushing these objects away. Some recent discoveries have even shown, if not directly, made a very convincing argument for the existence of dark matter. Now comes the weird twist. It's well known that our region of space is remarkably devoid of matter. Yes, there are stars and planets where ever we look. But outside our local area there is a veritable vacuum containing almost no matter. Some scientists have put forth that this lack of matter can "warp" our perception of the space around us. If this is the case then light coming through this void would be distorted in such a manner as to make it appear as though far reaching objects were moving away from us in an ever accelerating manner. One experiment that can help clear up this inconsistency is the upcoming Joint Dark Energy Mission, planned by Mission and the US Department of Energy, and set to launch in 2014 or 2015, hopes to measure the expansion of the universe precisely by observing a large number of supernovae.

<- more ->

Dark Flow may be sucking in huge portions of our Universe

You ready for something REALLY freaky? Forget about dark matter, lets consider for a moment DARK FLOW. Hair on the back of your neck standing up yet? No? It will. An article in IO9 writes that: there is a force called "dark flow" that exists outside our universe, and it's tugging several galaxy clusters at 2 million mph toward an empty spot in space. Unlike the localized pull of dark matter, Dark flow is a force that's operating at a universe level to push enormous chunks of matter around. And weirder yet: a group of astronomers say that this dark flow comes from a place where constants like time don't exist — nor do stars and galaxies. Our part of the cosmos, our universe may in fact be only a small bubble of space time. There could be other parts of the cosmos beyond this bubble that we cannot see. In these regions, space-time might be very different, and likely doesn't contain stars and galaxies. It could include giant, massive structures much larger than anything in our own observable universe. These structures are what researchers suspect are tugging on the galaxy clusters, causing the dark flow. One reason that we may not be able to see even a hint of these structures or other regions is that they have been pushed so far away by the initial expansion of our universe that the time it would take light from these areas takes longer than our universe is old to reach us.

<- io9 article via space.com article ->

Telescope at South Pole searches for Dark Matter

At seven stories tall and a main mirror 32 ½ feet across, it's a big telescope by anyone's estimation. Situated at the south pole, the aptly named South Pole Telescope is on a mission searching for the most powerful, plentiful but elusive substance in the universe — dark energy. Dark energy is a mysterious force so powerful that it has already overruled the laws of gravity, it is pushing galaxies away from one another, causing the universe to expand at an ever faster rate. Though dark energy is believed to account for 70 percent of the mass of the universe, it is invisible and virtually undetectable. Nobody knows what it is, where it is or how it behaves. The South Pole Telescope has begun to search the southern polar heavens for evidence of the elusive stuff. Controlled remotely from the University of Chicago, the $19.2 million telescope has quickly succeeded in its first mission: finding unknown galaxy clusters, clues to the emergence of dark energy.

Click here for a description of the construction of this amazing scope and the science it hopes to complete.

Wikipedia article on the telescope

article from Pantagraph.com

Universe being destroyed by mistake

Humanity may be accidentally hastening the end of the entire universe. Oops. To any and all other lifeforms out there in cosmos, sorry! Our bad!

It all comes down to quantum mechanics and the bizarre fact that subatomic thingamabobs behave differently if someone is watching them. Especially those peeking at dark matter...

One can imagine physicists Laurel and Hardy: "Stanley?...Now look what you made me do!"

Image courtesy Cinema Fantastique gallery

Ringside watchers differ on 3 billion year old brawl

Say you're in the taproom at the Restaurant at the end of the Universe. Down the bar, one galactic cluster drunkenly bumps into another. Before you know it, they are entangled in a deadly clash so terrible, they're knocking the very dark matter out of each other!

That's what last August, astronomer Douglas Clowe, then at the University of Arizona and his colleagues reported taking place about 3 billion light-years from here in the appropriately-named Bullet Cluster.

But now a Canadian team of researchers led by John W. Moffatt, PhD argues that what the Yanks thought they saw wasn't dark matter at all. Instead, the intermingling of the two vast bodies is resulting in a Modified Gravity event or "MOG" that has bent light passing through the non-dark matter of each cluster from even more distant stellar formations in slightly different ways, giving the appearance, if not the reality of a 'dark" form of matter. Moffatt says their Modified Gravity theory predicts that the force of gravity changes with distance. Is Einstein spinning in his grave?

Back in that restaurant bar, imagine you're watching the two multistellar bodies slowdancing through the lens of your partially filled glass beer mug, while you move it nearer and farther from your eye, and you'll be about right.

Astronomer Clowe and companions stand by their claims, however. That's dark matter out there, they believe.

NASA photo

Hubble spots ring of dark matter

Astronomers have found one of the best pieces of evidence for the existence of dark matter. They have identified what appears to be a ghostly ring in the sky which is made up of this enigmatic substance. Using the Hubble Space Telescope, the scientists have established that the ring formed long ago after a colossal smash-up between two galaxy clusters.

click article title to go to complete article

Submitted by Shaun Saunders

Hubble makes 3D dark matter map

Thanks to Shaun Saunders for this really neat tie in! :

Astronomers have mapped the cosmic "scaffold" of dark matter upon which stars and galaxies are assembled.

Dark matter does not reflect or emit detectable light, yet it accounts for most of the mass in the Universe.

The study, published in Nature journal, provides the best evidence yet that the distribution of galaxies follows the distribution of dark matter.

Ordinary matter - gas, stars, planets and galaxies - makes up just one-sixth of all matter in the Universe. The remainder is unseen.

While previous studies of dark matter relied on simulations, this one details its large-scale distribution in 3D.