How big is our Galaxy.

Alright, we're starting to get to some really big numbers. To help an old man understand this, let me ask a few more questions.So a Wall might contain 10 Million Galaxies and a Filament about 1 Million Galaxies.Is there more than one Wall? More than one Filament?

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Aslan is not a Tame Lion

Several hundred each, yeilding an overall picture of the universe which looks like this: This is a bit better though:
No webpage found at provided URL: http://www.pparc.ac.uk/Ps/aac/images/box.jpgThis message has been edited by Son Goku, 01-13-2006 10:09 PM

Okay, so let me summarize.There are several hundred walls, each wall contains about 10 Million Galaxies.There are several hundred filaments, each filament contains about 1 Million Galaxies.So at a minimum there is no less than 2 Billion Galaxies.Is that correct?

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Aslan is not a Tame Lion

Yeah, pretty much.
The actual number ends up being around 100 billion galaxies. There is really several thousand filaments, in the tens of thousands range, which I should have said instead of "several hundred each". Although the figure for the walls is still in the hundreds.Add in the free galaxies, which lie outside the walls and filaments and you get around 100 billion.This message has been edited by Son Goku, 01-13-2006 11:20 PM

Okay, so 100 Billion Galaxies.How many stars might that be?This message has been edited by jar, 01-13-2006 10:13 PM

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Aslan is not a Tame Lion

About 70-72 sextillion or 70,000,000,000,000,000,000,000.

That's a bunch of stars.Let me ask you a question.What would night look like if the Biblical Creationists happen to be right and all those stars are in a sphere that's 6000 light years in radius based on the earth?.

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Aslan is not a Tame Lion

Not pleasant.Fitting that amount of matter into a sphere with a radius of 6,000 light years would create a universal blackhole. However since the gravitational gradient would be slight, lets be generous and assume Earth isn't destroyed once the horizon is formed and concentrate only on the star light.Which would be equivalent to swimming around in the sun's core. The energy density would be such that atomic bonding would break down and thats before I get to the Quantum Field Theory effects.Basically the Star light alone, ignoring the gravity, would make chemistry impossible.This message has been edited by Son Goku, 01-13-2006 11:37 PM

Okay, so what would be the smallest universe that would still allow life on earth?Is it possible to even make such an estimate?

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Aslan is not a Tame Lion

At least 16 billion light years. Although that is just going on what radius wouldn't be cataclysmic.

SO:If life exists...and the stars and galaxies we see exist...the universe has to be at least 16 Billion years old?

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Aslan is not a Tame Lion

Yeah, pretty much and there isn't really any way around that fact.

That's larger than our universe! Did you mean that? You could shrink the universe considerably before there would be much of a problem...

Beautiful picture - thanks. Wish I'd thought of it Don't get me wrong, the night sky is one of the most beautiful aspects of creation... but sometimes I wish we could do away with the stars and just see the galactic background in all its glory. I guess a trip to the observation point that makes an equi triangle with Andromeda and the Galaxy would be truly awe-inspiring

You mean the observable universe, through the lens of inflation as it were. The light we see from 13 point something billion light-years away, which represents the edge of the observable universe, isa) 13ish billion years oldb) stretched by continued expansion such that it was only say 2 billion light years away when it leftc) and subject to continued expansion also in the sense that the location the light left from is now perhaps 78 billion light-years awayOr am I missing the whole point?