News:

Forum is currently set to Admin Approval for New Members
Pegasus Gofundme website



Main Menu

Cosmic 'web' seen for first time

Started by sky otter, January 21, 2014, 05:43:00 AM

Previous topic - Next topic

sky otter



http://www.bbc.co.uk/news/science-environment-25809967



Cosmic 'web' seen for first time


By Simon Redfern Reporter, BBC News
20 January 2014 Last updated at 09:05 ET



An intense quasar can, like a flashlight, illuminate part of the surrounding cosmic webThe hidden tendrils of dark matter that underlie the visible Universe may have been traced out for the first time.

Cosmology theory predicts that galaxies are embedded in a cosmic web of "stuff", most of which is dark matter.

Astronomers obtained the first direct images of a part of this network, by exploiting the fact that a luminous object called a quasar can act as a natural "cosmic flashlight".

Details of the work appear in the journal Nature.

The quasar illuminates a nearby gas cloud measuring two million light-years across.
"
In this case we were lucky that the flashlight is pointing toward the nebula and making the gas glow"
Sebastiano Cantalupo

University of California, Santa Cruz
And the glowing gas appears to trace out filaments of underlying dark matter.

The quasar, which lies 10 billion light-years away, shines light in just the right direction to reveal the cold gas cloud.

For some years, cosmologists have been running computer simulations of the structure of the universe to build the "standard model of cosmology".

They use the cosmic microwave background, corresponding to observations of the very earliest Universe that can be seen, and recorded by instruments such as the Planck space observatory, as a starting point.

Their calculations suggest that as the Universe grows and forms, matter becomes clustered in filaments and nodes under the force of gravity, like a giant cosmic web.

The new results from the 10-metre Keck telescope in Hawaii, are reported by scientists from the University of California, Santa Cruz and the Max Planck Institute for Astronomy in Heidelberg.

They are the first direct observations of cold gas decorating such cosmic web filaments.

The cosmic web suggested by the standard model is mainly made up of mysterious "dark matter". Invisible in itself, dark matter still exerts gravitational forces on visible light and ordinary matter nearby.

Massive clumps of dark matter bend light that passes close by through a process called gravitational lensing, and this had allowed previous measurements of its distribution.

But it is difficult to use this method to see very distant dark matter, and cold ordinary matter remains tricky to detect as well.

The glowing hydrogen illuminated by the distant quasar in these new observations traces out an underlying filament of dark matter that it is attracted to it by gravity, according to the researchers' analysis.

"This is a new way to detect filaments. It seems that they have a very bright quasar in a rare geometry," Prof Alexandre Refregier of the ETH Zurich, who was not involved in the work, told BBC News.

"If indeed gravity is doing the work in an expanding Universe, we expect to see a cosmic web and it is important to detect this cosmic web structure."

In the dark

He added: "What is expected is that the dark matter dominates the mass and forms these structures, and then the ordinary matter, the gas, the stars and everything else trace the filaments and structures that are defined by the dynamics of the dark matter."

"Filaments have been detected indirectly before using gravitational lensing, which allows us to see the distribution of the dark matter.

"Part of the ordinary matter has formed stars, which we can see, but another component is the gas. If the gas is very hot it emits X-rays and can be seen using X-ray telescopes. Other techniques to detect cooler gas now include the method described here."

Sebastiano Cantalupo, lead author of the article, and others have used the same method previously to look for glowing gas around quasars, and had seen dark galaxies.

"The dark galaxies are much denser and smaller parts of the cosmic web. In this new image, we also see dark galaxies, in addition to the much more diffuse and extended nebula," Dr Cantalupo, from UCSC, explained.

"Some of this gas will fall into galaxies, but most of it will remain diffuse and never form stars.

"The light from the quasar is like a flashlight beam, and in this case we were lucky that the flashlight is pointing toward the nebula and making the gas glow. We think this is part of a filament that may be even more extended than this, but we only see the part of the filament that is illuminated by the beamed emission from the quasar."

While the observations support the cosmological simulations' general picture of a cosmic web of filamentary structures, the researchers' results suggest around 10 times more gas in the nebula than predicted from typical computer simulations.

They postulate that this may simply be due to limitations in the spatial resolution of the current models, or, more interestingly perhaps, may be because the current grid-based models are missing some aspect of the underlying physics of how galaxies form, evolve, and interact with quasars.

"We now have very precise measurements of the amount of ordinary matter and dark matter in the Universe," said Prof Refregier.

"We can only observe a fraction of the ordinary matter, so the question is what form the remainder takes. These results may imply that a lot of it is in the form detected here."



.........................





Dark energy and dark matter mysteries
Gravity acting across vast distances does not seem to explain what astronomers see
Galaxies, for example, should fly apart; some other mass must be there holding them together
Astrophysicists have thus postulated "dark matter" - invisible to us but clearly acting on galactic scales
At the greatest distances, the Universe's expansion is accelerating
Thus we have also "dark energy" which acts to drive the expansion, in opposition to gravity
The current theory holds that 68% of the Universe is dark energy, 27% is dark matter, and just 5% the kind of matter we know well
.

...................................


More on This Story
Related StoriesHow close are we to finding dark matter? 18 NOVEMBER 2013, SCIENCE & ENVIRONMENT
A post-Higgs Cern has its eye on 'dark Universe' mysteries 09 OCTOBER 2013, SCIENCE & ENVIRONMENT
Images detail dark matter mystery 09 JANUARY 2012, SCIENCE & ENVIRONMENT
Cosmic crash unmasks dark matter 30 AUGUST 2008, SCI/TECH

A51Watcher


Norval

Quote from: A51Watcher on January 21, 2014, 06:33:43 AM

That image is AMAZING sky!!  :o

Does that remind anyone of anything?


WOW


, , why yes, , my old leather coat. 


Sorry, , sometimes I do try to be funny,, ,   :-[
It's the questions that drive us, , , the answers that guide us.
What will you know tomorrow? Have a question?
Send me an email at craterchains@yahoo.com

Cosmic4life

Quote from: A51Watcher on January 21, 2014, 06:33:43 AM

That image is AMAZING sky!!  :o

Does that remind anyone of anything?


WOW

Hmmm yes .... Neurons .... Synapses .... Cognitrons ..... the Neural network of a Brain.

C..

sky otter

#4
.... Neurons .... Synapses .... Cognitrons ..... the Neural network of a Brain.

yeah that   ;D

here's the link to the original.. i've become a bit skeptic on the above pic belonging to this particular study..sigh

http://www.nature.com/nature/index.html

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12898.html

pictures at the link

A cosmic web filament revealed in Lyman-? emission around a luminous high-redshift quasar
Sebastiano Cantalupo,1, 2 Fabrizio Arrigoni-Battaia,3 J. Xavier Prochaska,1, 2, 3 Joseph F. Hennawi3 & Piero Madau1
AffiliationsContributionsCorresponding author Journal name:
Nature
Year published:
(2014)DOI:
doi:10.1038/nature12898
Received25 February 2013 Accepted20 November 2013 Published online19 January 2014



ok a bit more looking and i think it goes here (the top photo)

http://www.bbc.co.uk/news/science-environment-16477774
9 January 2012 Last updated at 14:07 ET

Dark matter hints in widest-yet view of dark mystery
By Jason Palmer

Science and technology reporter, BBC News, Austin, Texas

Sinny

Not really a worthy reply -

But I've seen this before published in the 90's - why's it suddenly news now? lol

And not just here, it seems to have taken the net by 'storm'.
"The very word "secrecy" is repugnant in a free and open society"- JFK

starwarp2000

Quote from: Sinny on January 22, 2014, 01:53:12 PM
Not really a worthy reply -

But I've seen this before published in the 90's - why's it suddenly news now? lol

And not just here, it seems to have taken the net by 'storm'.

Because it was discovered back then and nobody cared!

Of course now all the Know-it-alls on FarceBook, Twitthead and Rumblr think that it is breaking news.
Tomorrow morning they will discover toast.... "Oh! Wow how do they get it so brown!"  ;D ;)
Sit down before fact like a small child, and be prepared to give up every preconceived notion, follow humbly wherever and to whatever abyss nature lead, or you will learn nothing. —T. H. Huxley

sky otter



QuoteBut I've seen this before published in the 90's - why's it suddenly news now? lol

sinny..can you give any references as to where you saw it..i must have missed it back then

and wow you're older thasn i thought.. ;)  or  you are only referencing when it was published..?

thanks

starwarp2000

#8
Quote from: sky otter on January 22, 2014, 03:55:38 PM

sinny..can you give any references as to where you saw it..i must have missed it back then

and wow you're older thasn i thought.. ;)  or  you are only referencing when it was published..?

thanks

Not trying to butt in here, Sky, but I thought I would save you (And Sinny) some searching for those articles.

QuoteHowever, in the early 1990s, quasar spectra taken by Lennox Cowie and Antoinette Songaila on the newly commissioned Keck telescopes revealed heavy elements far removed from any galaxy. Their discovery suggested that the chemical pollution of intergalactic space was much more efficient than originally believed.

http://www.americanscientist.org/issues/issue.aspx?id=922&y=0&no=&content=true&page=3&css=print

QuoteIn the early 1990s, astro-physicists studied the cosmic microwave background (CMB) to determine the velocities of our Local Group of galaxies. The Local Group consists of the Milky Way, Andromeda, and several dwarf galaxies. This group of galaxies tends to travel together because of their mutual gravity attraction. Their speed is roughly two million miles an hour also towards the Great Attractor.

http://www.outerspacecentral.com/cosmic_web_page.html

They even used the cosmic web image from that last website (From the 90s) for the 'new' article that you posted.
Glad to be of assistance.  :)

Edit: Added some more

http://disinfo.com/2011/07/our-brains-neurons-look-exactly-like-the-structure-of-the-universe/

http://www.dapla.org/earth_brain.htm

Sit down before fact like a small child, and be prepared to give up every preconceived notion, follow humbly wherever and to whatever abyss nature lead, or you will learn nothing. —T. H. Huxley

Sinny

#9
Quote from: sky otter on January 22, 2014, 03:55:38 PM

sinny..can you give any references as to where you saw it..i must have missed it back then

and wow you're older thasn i thought.. ;)  or  you are only referencing when it was published..?

thanks

Published, and I'll do my best.

ETA: Oh never mind, thanks Starwarp.
"The very word "secrecy" is repugnant in a free and open society"- JFK

sky otter



hey starwarp thanks..headin off to read

A51Watcher