Conference 7.286::space

	This discussion would be more fitting in the ASTRONOMY notes file.

>    
>    	Okay, what I whant to know if that if this thing is so blasted BIG
>    why didn't we find sooner? The telescope that they used is pretty small
>    compared to all the other bigger telescopes in the world. 
>

	I believe that the great wall is the same thing as the recently
	anounced great attractor (am I not right?).  We have known about
	the galaxies that make-up the great wall/great atrractor for
	some time, however it wasn't until recently that scientists dis-
	covered that these galaxies are all gravitationally atracted to
	each other, hence making them one very large object!  This was
	determined by measuring the red shifts of each galaxie.

	The name great attactor comes from the fact that not only are 
	all these galaxies attracted to one another, but are also 
	attracting other groups of galaxies into the attractor itself
	- including ours.  Interestingly, there appears to be another 
	attractor future away.

	The most recent issue of Sky & Telescope and an issue of Scientific
	American from early last summer each have a good article on the
	great attractor/wall.
	

    heck this is just the rim of the beaker  :+)
    jb
    

  I don't understand how clumps prove or disprove the big bang one way or the
other. I don't think anyone understands what would cause a big bang, and if
that is so, who knows what strange things could have been going on when it
happened? I realize that there are all sorts of theories as to what the
universe looked like at various fractions of a second after the big bang but
don't these all assume that it happened at one moment and that nothing near by
interfered with it's development? 

  Maybe the big bang was a series of events that happened over a short peroid
of time where masive fields of energy converted to matter. Maybe there was
"old matter" near by when it happened.

  If it was not one event that happened at one moment, or if the energy that
created the big bang was not uniform, there could be all sorts of reasons why
there are clumps. Maybe it was a series of explosions over the course of a
microsecond that interfered with each other to some extend. Maybe not. Who
knows for sure?

  George

    George is precisely correct.  Clumps do not prove or disprove anything
    about the big bang.  In point of fact some of the astronomers I have
    heard talk about this say that even with clumps the distribution of
    mass in the universe may be pretty uniform, since no one really knows
    about all that "cold dark matter" that is necessary for some
    calculations.  Maybe the cold dark matter is very uniform and just the
    galaxy's are non-uniform and some astronomers require that the total
    mass of the universe be 99% cold dark matter.
    
    Tony

RE. 581.4 

>
>  Clumps do not prove or disprove anything about the big bang.  
> 

	True, clumps in the universe do not disprove the big bang,
	however these clumps do suggest how big banged behaved.

	Ken

    Why didn't they see this big thing sooner?  Actually, they did, but
    only in 2 dimensions, not 3.  If I remember correctly, many of the
    galaxies are visible.  It's only when they started to build a 3
    dimensional map did they realize that they constructed a "wall".
    
    Joe
    

    Oh, I didn't realize that having a 3D map made much of a difference. It
    still blows my mind that this relatively small outfit in Cambridge made
    this 3D map before anyone else. Well I hope that this information is
    enough to get federal funding to investigate it more.
    
    	-Matt
    

RE:          <<< Note 581.7 by NETMAN::COHEN "Nothing is EVER easy..." >>>

>    Well I hope that this information is
>    enough to get federal funding to investigate it more.

Why federal funding?  Government (tax) money isn't automatically any better
than private-sector money.
						-- Tom

RE               <<< Note 581.8 by LHOTSE::DAHL "Tom Dahl, CDMS" >>>

>Why federal funding?  Government (tax) money isn't automatically any better
>than private-sector money.

  Nice thought Tom, but somehow I don't think that any venture capital
company is going to believe that there is a profit in mapping Glactic
walls. Maybe, but I doubt it.

  George

Maybe rand mc nalley will make a galactic wall map arh arh arh... 8^)

RE:                     <<< Note 581.9 by PAXVAX::MAIEWSKI >>>

I entered my comment since I thought it was odd that government money was
specifically suggested.

>  ...I don't think that any venture capital
>company is going to believe that there is a profit in mapping Glactic
>walls.

Who said anything about for-profit?  There are lots of observatories and the
like which get private funding with no profit motive (e.g. from Universities).
						-- Tom

RE              <<< Note 581.11 by LHOTSE::DAHL "Tom Dahl, CDMS" >>>

>Who said anything about for-profit?  There are lots of observatories and the
>like which get private funding with no profit motive (e.g. from Universities).

  Where do you think the Universities get their money? To say that they are
part of the private sector is really just a technacality. They are highly
subsidised by government through direct grants and indirectly through
student loans and Pell grants, all of which comes from the government
(i.e. taxes).

  George

RE:                     <<< Note 581.12 by PAXVAX::MAIEWSKI >>>

Okay.  I've never dealt much with public Universities, so I don't know much
about typical funding sources.  I went to a private college who's endowment
was funded mostly through individual and corporate grants, if I recall
correctly.  (Just a few years ago they built an observatory housing either an
18 inch or 24 inch reflector, don't recall which.  I visited it recently; I
wish it had been there when I was a student!)
						-- Tom

    Regardless of funding.
    
    From what I gather from the discussion, there are not really any
    new galaxies that have been discovered. Just that their organization
    is different from what was believed before? Damn. I was hoping this
    could solve the "missing mass" problem.
    
    steve p

The September issue of the British periodical Astronomy Now carries an article
on pages 32-33 entitled "A Map of the Universe", in which the recent
discoveries of "walls" of galaxies and other large-scale structure are
discussed.

The article presents a set of maps of this large scale structure, consisting of
semi-circular segments of the Universe out to about 500 million light-years. In
each case, our own position is at the centre of the circle.

The immediate impression, on looking at these maps, is that the structures are
mainly radial to the Earth's position. To my eye (and without any detailed
measurement or analysis of the maps), it looks as though the structures might
be due to some kind of systematic error in the distance measurements, rather
than any real large scale structure.

Has anyone else seen this article? Any comments on the maps?


Dave Hazel