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chaloobi
SFN Regular
1620 Posts |
 Posted - 09/29/2008 : 10:01:41
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Apparently 700 far away clusters of galaxies are all rushing in the same direction toward something astronomers can't see. They believe whatever it is might be on the other side of the horizon created by the early universe inflating faster than the speed of light. If that's the case, how can we ever know what's out there? Pretty cool stuff...
Flowing Toward Oblivion?
By Phil Berardelli
ScienceNOW Daily News
26 September 2008
Along with dark matter and dark energy, astronomers can now add dark flow to the lexicon of cosmic mysteries. Researchers have discovered that 700 distant clusters of galaxies, gas, and dust are all being pulled in the same direction, apparently toward something invisible and possibly very large, confounding current cosmological models. So far, what that "something" is remains speculative, but it could turn out to be a vestige of the universe's earliest days.
Shortly after the big bang occurred some 13.7 billion years ago, cosmologists think, the universe underwent a brief period that defied current physical laws. The theory goes that during this time, called inflation, space itself expanded at a rate much, much faster than the speed of light. As a result, some of the matter formed with the big bang was pulled more than 13.7 billion light-years away--so far that its light hasn't reached us yet. As a result, that matter can't be observed--or at least, so cosmologists thought.
But now a team led by astrophysicist Alexander Kashlinsky of NASA's Goddard Space Flight Center in Greenbelt, Maryland, has unearthed what could be indirect evidence of inflation. The researchers had been surveying the motion of 700 clusters of galaxies to test an unrelated astronomical phenomenon when they made a startling discovery: All 700 clusters are flowing basically in the same direction and at speeds of as much as 1000 kilometers per second--or more than 30 times faster than Earth revolves around the sun. As the team reports in this week's online edition of Astrophysical Journal Letters, the clusters, which appear headed toward a region of the sky where the constellation Centaurus resides, are moving faster than they should be if their acceleration were due only to dark energy, the mysterious force discovered a decade ago that is slowly ripping the cosmos apart.
It was "a huge surprise," says astrophysicist and co-author Harald Ebeling of the University of Hawaii, Honolulu. The big question, he says, is what is generating the flow. The volume of galaxy clusters affected is much too big to be reacting to some single, massive object, Ebeling says. Instead, the team speculates that the flow is moving the clusters toward an irregularity in the mass distribution of the universe that was already in place before inflation began. If so, Ebeling says, the flow should extend even farther across the universe, and the researchers could have the answer when they examine the motion of an even larger and deeper catalog of close to 1500 galaxy clusters. "We should know more in a few years," he adds.
It's an "intriguing" finding, says astrophysicist Mike Hudson of the University of Waterloo in Ontario, Canada. Hudson, who with colleagues has submitted a related paper of his own observations to the Monthly Notices of the Royal Astronomical Society, says the direction of the flow agrees "very well" with his own findings, though those of Kashlinsky's team cover a greater distance and have found a much greater velocity. Hudson recommends awaiting confirmation of the results by other groups using other surveys, but "if this result holds up, then theorists will certainly have to make some major revisions to the standard cosmological model." |
Link: http://sciencenow.sciencemag.org/cgi/content/full/2008/926/1?rss=1
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-Chaloobi
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Edited by - chaloobi on 09/29/2008 10:02:11
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 09/29/2008 : 10:06:38 [Permalink]
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Man, I knew I left my Ego somewhere.
This is one of those things that makes Einstein cry at night, no matter what happens all we can do is speculate about these falling clusters. Very intriguing though, I wonder if they'll find any other flows to other regions beyond our sphere of influance. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 09/30/2008 : 00:16:28 [Permalink]
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Maybe, like Larry Niven's "Fleet of Worlds," they are running away from something, not toward something.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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chaloobi
SFN Regular
1620 Posts |
 Posted - 09/30/2008 : 04:47:50 [Permalink]
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Originally posted by HalfMooner
Maybe, like Larry Niven's "Fleet of Worlds," they are running away from something, not toward something.
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Imagine the scale: they looked at 700 clusters of galaxies. I don't know how many is in a cluster, but lets say, for example, there's an average of 15 galaxies in each cluster. That's:
15 * 700 = 10,500 galaxies.
Now, there's about 200 billion stars in the Milky Way. I don't know if the MW is typical, but let's say it is. So:
10,500 * 200 billion = 2 trillion, 100 billion stars.
Now, imagine moving that as an engineered project. You're way out of Niven's league here and well into Stephen Baxter. Actually, you may be out of Baxter's league too. |
-Chaloobi
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Simon
SFN Regular
USA
1992 Posts |
Posted - 09/30/2008 : 08:35:41 [Permalink]
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| Woaw... That is... woaw! |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 09/30/2008 : 09:32:17 [Permalink]
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| Galaxy clusters can have 1000 galaxies or more in them though they probably average about 100 our local group has about 40, the average galaxy has about 150 Billion stars, Andromeda, which will soon eat the Milky Way has about a trillion stars. In addition to the mass of the galaxies, the mass of the dark matter comas which surround the clusters is also being pulled. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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chaloobi
SFN Regular
1620 Posts |
Posted - 09/30/2008 : 13:09:29 [Permalink]
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Originally posted by BigPapaSmurf
Galaxy clusters can have 1000 galaxies or more in them though they probably average about 100 our local group has about 40, the average galaxy has about 150 Billion stars, Andromeda, which will soon eat the Milky Way has about a trillion stars. In addition to the mass of the galaxies, the mass of the dark matter comas which surround the clusters is also being pulled.
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Ok, based on your averages...
700 clusters * 100 galaxies/cluster = 70,000 galaxies
150 billion stars / galaxy * 70,0000 galaxies =
10 trillion, 500 billion stars all moving toward something that can't be seen because it's so far away it's light hasn't reached us yet. Whatever it is, it's huge. That or more likely we're first seeing what will be another fundamental change in our understanding of the universe. First there was the discovery the universe is expanding. Then there was the discovery that the expansion is in fact accelerating. Now we see a huge region of the galaxy apparently flowing someplace beyond our ability to see.... wtf. |
-Chaloobi
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 10/01/2008 : 05:17:09 [Permalink]
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| Yeah but the light will never reach us, dark energy is expanding the universe faster than the speed of light, as time goes on we will see less and less. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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chaloobi
SFN Regular
1620 Posts |
Posted - 10/01/2008 : 07:28:14 [Permalink]
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Originally posted by BigPapaSmurf
Yeah but the light will never reach us, dark energy is expanding the universe faster than the speed of light, as time goes on we will see less and less.
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I'm sure faster than light travel is somewhere in our future. Then we can just go there.  |
-Chaloobi
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 10/01/2008 : 07:45:31 [Permalink]
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Well considering the fastest craft we've ever made* only reached .0002c Im not so certain.
*Helios probe during Solar slingshot. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Simon
SFN Regular
USA
1992 Posts |
Posted - 10/01/2008 : 08:36:42 [Permalink]
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Originally posted by BigPapaSmurf
Yeah but the light will never reach us, dark energy is expanding the universe faster than the speed of light, as time goes on we will see less and less.
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But, doesn't light travel at the same speed regardless of the direction it is going?
Example to clarify: if a train is immobile and another train is going away from us at 20mph and a person jump from each train in our direction at 15 mph... The guy from the immobile train will come toward us at 15mph while the other one will appear to move backward at 5mph; ok?
But, if I am not mistaken, light is different and will appear to have the same speed regardless.
So, light emitted by an object flying away from us will have the same apparent speed than light flying toward us.
So, the speed of the objects behind the horizon should not affect light speed... It just that light is going to take longer and longer to reach us. But it should still reach us... eventually (unless it is absorbed before).
Or I am wrong (again). |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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astropin
SFN Regular
USA
970 Posts |
Posted - 10/01/2008 : 09:08:36 [Permalink]
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Originally posted by BigPapaSmurf
Yeah but the light will never reach us, dark energy is expanding the universe faster than the speed of light, as time goes on we will see less and less.
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 I've never heard that before....FASTER than the speed of light? |
I would rather face a cold reality than delude myself with comforting fantasies.
You are free to believe what you want to believe and I am free to ridicule you for it.
Atheism:
The result of an unbiased and rational search for the truth.
Infinitus est numerus stultorum |
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chaloobi
SFN Regular
1620 Posts |
Posted - 10/01/2008 : 09:52:39 [Permalink]
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Originally posted by BigPapaSmurf
Well considering the fastest craft we've ever made* only reached .0002c Im not so certain.
*Helios probe during Solar slingshot.
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Patience. We've only been flying for about a hundred years and and going to space for half that time. In another hundred years, who knows? (we won't...  ) |
-Chaloobi
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chaloobi
SFN Regular
1620 Posts |
Posted - 10/01/2008 : 10:00:49 [Permalink]
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Originally posted by astropin
Originally posted by BigPapaSmurf
Yeah but the light will never reach us, dark energy is expanding the universe faster than the speed of light, as time goes on we will see less and less.
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I've never heard that before....FASTER than the speed of light?
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Now that I think of it, I haven't heard that either.
So I looked it up:
How Fast is the Universe Expanding?
The expansion or contraction of the universe depends on its content and past history. With enough matter, the expansion will slow or even become a contraction. On the other hand, dark energy drives the universe towards increasing rates of expansion. The current rate of expansion is usually expressed as the Hubble Constant (in units of kilometers per second per Megaparsec, or just per second).
<snip>
the best estimate is 70.8 (km/sec)/Mpc (give or take 1.6 (km/sec)/Mpc). |
The snipped part goes into great detail about how the Hubble Constant is determined if anyone's interested.
http://map.gsfc.nasa.gov/universe/uni_expansion.html |
-Chaloobi
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 10/01/2008 : 10:22:02 [Permalink]
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It works like this,
Our universe is a loaf of bread dough with raisins in a line with spaces in between them,
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A-B-C-D-E-F-G-H-I-J
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Each raisin is a galaxy cluster each space is an intergalactic void, we let the bread rise for awhile and this happens,
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A--B--C--D--E--F--G--H--I--J
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Dark energy makes the spacetime between raisins/galaxies expand,
-Raisin A is moving away from Raisin B at one space per interval
(your constant perhaps?)
-Raisin A is moving away from Raisin J at nine spaces per interval
So while spacetime itself is expanding at a lesser rate it is essentially expanding in more than one place and the speeds compound. This is why in a Universe 13.7BYO the Universe is estimated to be 220BLY wide.
Thats how I understand it at least.
Edit: So let's say light moves at 8 spaces per interval and DE doubles every interval
A-B-C-D-E-F-G-H-I-J-K-L-M-N
^photon begins its journey towards N at point A
after one interval
A--B--C--D--E--F--G--H--I--J--K--L--M--N
^-------^photon has made it this far
after two intervals
A----B----C----D----E----F----G----H----I----J----K----L-etc.
--------------^-------^Photon has made it this far
Long story short, the photon will never make it to N, not only that but N will move away from the photon at ever increasing speeds. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
| Edited by - BigPapaSmurf on 10/01/2008 11:31:43 |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 10/01/2008 : 10:37:44 [Permalink]
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Also as the spaces get bigger the rate of expansion increases, which is why the acceleration is speeding up.
Immediatly after the bang the rate of expansion was near light speed, but was soon slowed due to gravity, as the empty spaces were small or not yet existant, dark energy was very weak at the start. After awhile the spaces grew to a size where DE overcame gravity and the verse could begin accelerating the expansion again at an exponential rate. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Dark Flow - Out there Beyond the Horizon
