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Fraser
2006-Jul-27, 05:43 PM
Astronomers have used the Subaru and Keck telescopes to discover gigantic filaments of galaxies stretching across 200 million light-years in space. These filaments, formed just 2 billion years after the Big Bang, are the largest structures ever discovered in the Universe. The filaments contain at least 30 huge concentrations of gas, each of which contains 10x the mass of the Milky Way.

Read the full blog entry (http://www.universetoday.com/2006/07/27/the-largest-structure-in-the-universe/)

iantresman
2006-Jul-27, 10:10 PM
So are these "Lyman alpha blobs" made of gas, plasma, or a mixture?

The original press release (http://subarutelescope.org/Pressrelease/2006/07/26/index.html) says the "gas" is glowing, which must imply a plasma?

Regards,
Ian Tresman

Explorer
2006-Jul-28, 06:38 PM
In what constellation or direction are these structures located?

ToSeek
2006-Jul-28, 08:33 PM
So far as I can tell the structure is in a field with RA and Dec of 22:17:33.82
+00:15:04.4. I believe that would put it in the constellation of Aquarius.

Explorer
2006-Jul-30, 05:56 PM
Thanks ToSeek.

That is very interesting - Aquarius - the Water Bearer. It is interesting because the Pisces - Perseus complex of galaxies located next to Aquarius, is co-moving with the Local Group and with the Virgo complex. We are all moving forward, more or less together in a steady stream towards a distant Centaurus, I believe.

In the original article the structure was said to be moving at 500 kilometres per second. I'm curious about whether that motion is relative to us (at 600 kps) or is it relative to the background radiation as our motion is? And, if the astronomers can tell if this motion has a direction itself?

I am trying to picture the local cosmos in relation to this co-moving mass of galaxies. If anyone knows a website related to the structure of the local cosmos, I would really appreciate checking it out. My searches have either been too much heavy on the mathematics or lack a lot of detail about this 'peculiar motion' as it has been called.

For instance, the WMAP site just removes this peculiar motion of 600kps and prefers to deal with the tiny fluctuations. I think this overall coherent motion is the real discovery of COBE.

antoniseb
2006-Jul-30, 07:52 PM
So are these "Lyman alpha blobs" made of gas, plasma, or a mixture?

Ummm. It would pretty much have to be a mixture. I expect that if you looked, you'd also see these blobs in the Lyman continuum.