Reference Article

from Wikipedia, the free encyclopedia

Large-scale structure of the cosmos

In physical cosmology, the term large-scale structure refers to the characterization of observable distributions of matter and light on the largest scales (typically on the order of billions of light-years).

Sky surveys and mappings of the various wavelength bands of electromagnetic radiation (in particular 21-cm emission) have yielded much information on the content and character of the universe's structure.

The organization of structure arguably begins at the stellar level, though most cosmologists rarely address astrophysics on that scale.

Stars are organised into galaxies, which in turn form clusters and superclusters that are separated by immense voids.

Prior to 1989, it was commonly assumed that virialized galaxy clusters were the largest structures in existence, and that they were distributed more or less uniformly throughout the universe in every direction.

However, based on redshift survey data, in 1989 Margaret Geller and John Huchra discovered the "Great Wall," a sheet of galaxies more than 500 million light-years long and 200 million wide, but only 15 million light-years thick.

The existence of this structure escaped notice for so long because it requires locating the position of galaxies in three dimensions, which involves combining location information about the galaxies with distance information from redshifts.

In April 2003, another large-scale structure was discovered, the Sloan Great Wall.

However, technically it is not a 'structure', since the objects in it are not gravitationally related with each other but only appear this way, caused by the distance measurement that was used.

One of the biggest voids in space is the Capricornus void, with an est. diameter of 230 million light years.

However in August 2007 a new supervoid was confirmed in the constellation Eridanus, which is nearly a billion light years across.

In more recent studies the universe appears as a collection of giant bubble-like voids separated by sheets and filaments of galaxies, with the superclusters appearing as occasional relatively dense nodes.

Note: This article excerpts material from the Wikipedia article "Large-scale structure of the cosmos", which is released under the GNU Free Documentation License.

See the following related content on ScienceDaily:


Related Videos

last updated on 2014-11-23 at 5:04 am EST

Powerful Camera Seeks Snapshots of Dark Energy

Powerful Camera Seeks Snapshots of Dark Energy

Reuters (Nov. 9, 2012) The most powerful sky-mapping instrument ever built is about to embark on a far-reaching survey of deepest space to find evidence of the theoretical force called Dark Energy. From a high plateau in Chile, the Dark Energy Camera is being pointed billions of light years into the cosmos in an effort by astronomers to answer questions about Dark Energy's influence over the expansion of our universe.
Powered by NewsLook.com
Scientists Find Hint of Dark Matter From Cosmos

Scientists Find Hint of Dark Matter From Cosmos

AP (Apr. 3, 2013) A cosmic ray detector on the International Space Station has found the footprint of something that could be dark matter, the mysterious substance that's never been directly observed but is believed to hold the cosmos together.
Powered by NewsLook.com
Spacecraft Gives "Baby Picture" of Universe

Spacecraft Gives "Baby Picture" of Universe

AP (Mar. 21, 2013) New results from looking at the split-second after the Big Bang indicate the universe is 80 million years older than previously thought, but core concepts in physics about the cosmos seem to be on the right track.
Powered by NewsLook.com
Did An Oklahoma TV Station Censor Evolution Out Of 'Cosmos'?

Did An Oklahoma TV Station Censor Evolution Out Of 'Cosmos'?

Newsy (Mar. 13, 2014) By accident or design, KOKH aired an ad spot over an evolution reference in Fox's "Cosmos" reboot Sunday. Video provided by Newsy
Powered by NewsLook.com

Related Stories


Share This



Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins