Colors of Quasars Reveal a Dusty Universe
February 26, 2009(PhysOrg.com) -- The vast expanses of intergalactic space appear to be filled with a haze of tiny, smoke-like "dust" particles that dim the light from distant objects and subtly change their colors, according to a team of astronomers from the Sloan Digital Sky Survey (SDSS-II), including a researcher from the University of California, Davis.
SDSS-II is the second step of the Sloan Digital Sky Survey, which since 2000 has used a 2.5-meter telescope coupled with a 120-megapixel camera and two spectrographs to probe the night sky from an observatory in New Mexico.
"Galaxies contain lots of dust, most of it formed in the outer regions of dying stars," said team leader Brice Ménard of the Canadian Institute for Theoretical Astrophysics. "The surprise is that we are seeing dust hundreds of thousands of light-years outside of the galaxies, in intergalactic space."
The new findings are reported in a paper titled "Measuring the galaxy-mass and galaxy-dust correlations through magnification and reddening," submitted to the journal Monthly Notices of the Royal Astronomical Society, and posted today at http://arxiv.org/abs/0902.4240 .
To discover this intergalactic dust, the team analyzed the colors of distant quasars whose light passes in the vicinity of foreground galaxies on its way to the Earth.
Dust grains block blue light more effectively than red light, explained astronomer Ryan Scranton of UC Davis, another member of the discovery team. "We see this when the sun sets: light rays pass through a thicker layer of the atmosphere, absorbing more and more blue light, causing the sun to appear reddened."
"We find similar reddening of quasars from intergalactic dust, and this reddening extends up to 10 times beyond the apparent edges of the galaxies themselves," said Scranton, who is an assistant researcher in the physics department.
The team analyzed the colors of about 100,000 distant quasars located behind 20 million galaxies, using images from SDSS-II. "Putting together and analyzing this huge data set required cutting-edge ideas from computer science and statistics,” said team member Gordon Richards of Drexel University. "Averaging over so many objects allowed us to measure an effect that is much too small to see in any individual quasar."
Supernova explosions and "winds" from massive stars drive gas out of some galaxies, Ménard explained, and this gas may carry dust with it. Alternatively, the dust may be pushed directly by starlight.
"Our findings now provide a reference point for theoretical studies," said Ménard.
Intergalactic dust could also affect planned cosmological experiments that use supernovae to investigate the nature of "dark energy," a mysterious cosmic component responsible for the acceleration of the expansion of the universe.
"Just like household dust, cosmic dust can be a nuisance," said Scranton. "Our results imply that most distant supernovae are seen through a bit of haze, which may affect estimates of their distances."
Intergalactic dust doesn't remove the need for dark energy to explain current supernova data, Ménard explained, but it may complicate the interpretation of high-precision distance measurements. "These experiments are very ambitious in their goals," said Ménard, "and subtle effects matter."
Provided by University of California, Davis
Nov 18, 2009 |
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Finally confirming what everyone already knew: Redshift != distance.
I only think distance will be adjusted for the galaxies/quasars that are really far away (beyond the barrier, etc).
There are still huge spaces between the galaxies, according to this article filled with a little dust (even a small atmosphere at earth has a huge impact on the light seen). So the amount of matter will probably not account for all the "lost" mass (which is the definition of dark matter in plain english).
If the size of the universe will be smaller than expected, the amount of mass that we see is a larger fraction. If im not mistaken, the amount of mass we see should make up for only 5% of the total matter. If the universe is indeed 20 times smaller in mass, then the universe should be 20^3 times smaller (8000 times). Then we would see a lot more gravitational effects.
Furthermore, this dust can't account for the effects see on almost each galaxy (rotational effects). Some findings may probably cancel out dark matter because we have found an explanation.
(i.e. the ocean was endless until someone found America (ok, he thought it was Indonesia, he sailed tight through Cuba but nobody is perfect)).
That is dust will leak out from between the larger interstellar spaces where local galactic gravity is at its weakest compared to other influences like electric charge. Solar winds from distant supernova and the like are enough to break the last tenuous bond of gravity.
So theories need to include the aspect of galaxies moving for billions of years: wobble of individual spinning galaxies as they orbit around the local cluster, the interactions of local galactic clusters and translation of the local clusters within the expanding galaxy.
So yes there will be more dust scattering than can be explained by "recent" solar winds and supernova ejecting dust violently from stationary galaxies.
If a galaxy has strong movement that should be detectable by the long teardrop dust effect pointing to its former position and thinning of dust in the direction it is moving.
On Energy, Mass, Gravity And Galaxies Clusters,
A Commonsensible Epilogue, And A Prologue To Life Evolution
Origin Of Gravity And Formation Of Life
http://www.scienc..._feeding
**The onset of big-bang's inflation started gravity, followed by formation of galactic clusters that behave "classically" as Newtonian bodies while continuously reconverting their shares of pre-inflation masses back to energy, and of endless intertwined evolutions WITHIN the clusters in attempts to resist this reconversion.
Astronomically there are two "physics", a "classical physics" behaviour of and between galactic clusters, and a "quantum physics" behaviour within galactic clusters.**
A. "Heavyweight galaxies in the young universe", at
http://www.scienc...universe
New observations of full-grown galaxies in the young universe may force astrophysicists to revise their leading theory of galaxy formation, at least as it applies to regions where galaxies congregate into clusters.
B. Some brief notes in "Light On Dark Matter?", at
http://www.physfo...ic=22994&st=0&#entry373127
- "Galaxy Clusters Evolved By Dispersion, Not By Conglomeration"
- Introduction of E=Total[m(1 D)]
- "Dark Energy And Matter And The Emperor's New Clothes"
- "Evolutionary Cosmology: Ordained Or Random"
- "%u201CMovie%u201D Of Microwave Pulse Transitioning From Quantum To Classical Physics"
- "Broken Symmetry" Is Physics' Term Of Biology's "Evolution"
- "A Glimpse Of Forces-Matter-Life Unified Theory"
C. Commonsensible conception of gravity
1. According to the standard model, which describes all the forces in nature except gravity, all elementary particles were born massless. Interactions with the proposed Higgs field would slow down some of the particles and endow them with mass. Finding the Higgs %u2014 or proving it does not exist %u2014 has therefore become one of the most important quests in particle physics.
However, for a commonsensible primitive mind with a commonsensible universe represented by
E=Total[m(1 D)], this conceptual equation describes gravity. It does not explain gravity. It describes it. It applies to the whole universe and to every and all specific cases, regardless of size.
2. Thus gravity is simply another face of the total cosmic energy. Thus gravity is THE cosmic parent of phenomena such as black holes and life. It is the display of THE all-pervasive-embracive strained space texture, laid down by the expanding galactic clusters, also noticed within the galactic clusters in the energy backlashes into various constructs of temporary constrained energy packages.
3. "Extrapolation of the expansion of the universe backwards in time to the early hot dense "Big Bang" phase, using general relativity, yields an infinite density and temperature at a finite time in the past. At age 10^-35 seconds the Universe begins with a cataclysm that generates space and time, as well as all the matter and energy the Universe will ever hold."
At D=0, E was = m and both E and m were, together, all the energy and matter the Universe will ever hold. Since the onset of the cataclysm, E remains constant and m diminishes as D increases.
The increase of D is the inflation, followed by expansion, of what became the galactic clusters.
At 10^-35 seconds, D in E=Total[m(1 D)] was already a fraction of a second above zero. This is when gravity started. This is what started gravity. At this instance starts the space texture, starts the straining of the space texture, and starts the "space texture memory", gravity, that may eventually overcome expansion and initiate re-impansion back to singularity.
D. Commonsensible conception of the forces other than gravity
The forces other than gravity are, commonsensibly, forces involved in conjunction with evolution within the galactic clusters:
http://royalsocie...?id=4770
The farthest we go in reductionism in Everything, including in Life, we shall still end up with wholism, until we arrive at energy. Energy is the base element of everything and of all in the universe. At the beginning was the energy singularity, at the end will be near zero mass and an infinite dispersion of the beginning energy, and in-between, the universe undergoes continuous evolution consisting of myriad energy-to-energy and energy-to-mass-to-energy transformations.
The universe, and everything in it, are continuously evolving, and all the evolutions are intertwined.
E. PS to "On Cosmic Energy And Mass Evolutions"
As mass is just another face of energy it is commonsensible to regard not only life, but mass in general, as a format of temporarily constrained energy.
It therefore ensues that whereas the expanding cosmic constructs, the galaxies clusters, are - overall - continuously converting "their" original pre-inflation mass back to energy, the overall evolution WITHIN them, within the clusters, is in the opposite direction, temporarily constrained
energy packages such as black holes and biospheres and other energy-storing mass-formats are precariuosly forming and "doing best" to survive as long as "possible"...
F. From "Strings Link the Ultracold with the Superhot"
http://www.scienc...Superhot
"Perfect liquids suggest theory%u2019s math mirrors something real.
When the universe was very young, and still superhot from the aftermath of the Big Bang, plasma should have been the only state of matter around. And that%u2019s what scientists at Brookhaven expected to see when they smashed gold ions together at 99.99 percent of the speed of light using a machine called RHIC (for Relativistic Heavy Ion Collider). RHIC physicists thought the ion collisions would melt the gold%u2019s protons and neutrons into a hot plasma of quarks and gluons at a temperature of a trillion kelvins, replicating conditions similar to those a microsecond after the birth of the universe. But instead of a gaslike plasma, the physicists reported in 2005, RHIC served up a hot quark soup, behaving more like a liquid than a plasma or gas."
G. The expectation of Brookhaven scientists was a bit unrealistic
The "aftermath of the Big Bang" lasted much less than 10^-35 seconds. This is evidenced by the fact that "Gravity Is THE Manifestation Of The Onset Of Cosmic Inflation Cataclysm":
http://www.the-sc...age#1950
and
http://www.the-sc...age#1982
With all respect due to the scientists at Brookhaven it is unrealistic to expect that they can recreate the state of pre big-bang energy-mass singularity. Commonsense is still the best scientific approach.
H. PS To "Gravity Limits Link Ultracold And Superhot": Our Inability To Create Singularity
a. From "Strings Link the Ultracold with the Superhot"
A new truth always has to contend with many difficulties,%u201D the German physicist Max Planck said decades ago. %u201CIf it were not so, it would have been discovered much sooner.%u201D
b. IMO gravity is attempted reversal of inflation
To me, a simple uninformed one, E=mc^2 is a derived formula, whereas E=Total[m(1 D)] is a commonsensical descriptive concept.
I intuitively regard both the ultracold and superhot liquids as being in a confined space and "striving but unable" to overcome D, to render D=0.
I also intuitively regard our accelerated collisions smashups as attempted "reverse inflations" in the sense that Newton's law of universal gravitation seems to me as "reverse inflation".
I. An epilogue and a prologue
Here ends the basic story of Energy, Mass, Gravity and Galaxies Clusters. For us, humans, this is the prologue to the story of Life's Evolution, briefly presented in "Updated Life's Manifest May 2009".
Dov Henis
(Comments from 22nd century)
http://blog.360.y...Q--?cq=1
Updated Life's Manifest May 2009
http://www.physfo...ic=14988]http://www.physfo...ic=14988[/url]&st=480&#entry412704
http://www.the-sc...age#2321
EVOLUTION Beyond Darwin 200
http://www.physfo...ic=14988]http://www.physfo...ic=14988[/url]&st=405&#entry396201
http://www.the-sc...age#1407
On The Origin Of Origins
Dark Matter-Energy And Higgs Particle?
Energy-Mass Superposition
The Fractal Oneness Of The Universe
All Earth Life Creates and Maintains Genes
A. On Energy, Mass, Gravity, Galaxies Clusters AND Life, A Commonsensible Recapitulation
http://www.the-sc...age#2125
The universe is the archetype of quantum within classical physics, which is the fractal oneness of the universe.
Astronomically there are two physics. A classical physics behaviour of and between galactic clusters, and a quantum physics behaviour WITHIN the galactic clusters.
The onset of big-bang's inflation, the cataclysmic resolution of the Original Superposition, started gravity, with formation - BY DISPERSION - of galactic clusters that behave as classical Newtonian bodies and continuously reconvert their original pre-inflation masses back to energy, thus fueling the galactic clusters expansion, and with endless quantum-within-classical intertwined evolutions WITHIN the clusters in attempt to delay-resist this reconversion.
B. Updated Life's Manifest May 2009
http://www.physfo...ic=14988&st=480&#entry412704
http://www.the-sc...age#2321
All Earth life creates and maintains Genes. Genes, genomes, cellular organisms - All create and maintain genes.
For Nature, Earth's biosphere is one of the many ways of temporarily constraining an amount of ENERGY within a galaxy within a galactic cluster, for thus avoiding, as long as possible, spending this particularly constrained amount as part of the fuel that maintains the clusters expansion.
Genes are THE Earth's organisms and ALL other organisms are their temporary take-offs.
For Nature genes are genes are genes. None are more or less important than the others. Genes and their take-offs, all Earth organisms, are temporary energy packages and the more of them there are the more enhanced is the biosphere, Earth's life, Earth's temporary storage of constrained energy. This is the origin, the archetype, of selected modes of survival.
The early genes came into being by solar energy and lived a very long period solely on direct solar energy. Metabolic energy, the indirect exploitation of solar energy, evolved at a much later phase in the evolution of Earth's biosphere.
However, essentially it is indeed so. All Earth life, all organisms, create and maintain the genes. Genes, genomes, cellular organisms - all create and maintain genes.
Dov Henis
(Comments from 22nd century)
http://profiles.y...MFQSDYEU