Niven scaled up... [spec]

Hi

i just realized a strikingly good(?) explanation for some observable
structure out there...

remember Larry Nivens 'Ringworld'[1]?
a SF story evolving around the concept of a huge ring-shaped structure
around a star, providing enormous habitable space... the idea being
the long term survival of the species. basically a _very_ slow escape
pod from the pen-ultimate(*) extinction level event for a species -
'something big and black'[2] in the center of the galaxy...

so with this we already imagined a species trying to move ONE solar
system...

imagine a species, having conquered a good deal more of the galaxy
than a few single star systems... and being able and willing to
prevent them from falling prey to the central black hole...
you know what you'd get?

Hoag's Object! [3]

SCNR
heng

--
(*) leaving only the heat death of the universe to contemplate
[1] http://en.wikipedia.org/wiki/Ringworld
[2] http://www.schlockmercenary.com/d/20010127.html - "In the grand
scheme of things, the milky way is just an accretion disk for a big
old black hole."
[3] http://en.wikipedia.org/wiki/Hoag's_Object

hoeskioeh RemoveThis @gmx.de wrote:

> i just realized a strikingly good(?) explanation for some observable
> structure out there...
>
> remember Larry Nivens 'Ringworld'[1]?
> a SF story evolving around the concept of a huge ring-shaped structure
> around a star, providing enormous habitable space... the idea being
> the long term survival of the species. basically a _very_ slow escape
> pod from the pen-ultimate(*) extinction level event for a species -
> 'something big and black'[2] in the center of the galaxy...

Galactic black holes do not cause all the stars to eventually be eaten.
After an active phase, they just sit there an orbit. Black holes do
not attract distant matter any differently than other massive objects
do. Nearby stars may wander close and get sucked in to a galactic black
hole, but distant starts simply orbit the galactic core, black hole and
all, without knowing or caring what lies at the center.

Through dynamical cooling, in the far future, you could start talking
about galaxies losing enough dynamic energy so that central black holes
form or grow, but that's in the far, far future, approaching the time
when all the stars have burned out anyway. Besides, if that's your
primary concern, it's far easier to just keep your star from being
sucked into the black hole rather than to equip it for interstellar
travel ...

> imagine a species, having conquered a good deal more of the galaxy
> than a few single star systems... and being able and willing to
> prevent them from falling prey to the central black hole...
> you know what you'd get?
>
> Hoag's Object! [3]

Ring galaxies are not formed by central black holes eating up all the
stars. They're caused by galactic interactions, where a compact galaxy
passes through a large spiral or elliptical galaxy, nearly face-on.
Hoag's Object's origins aren't well-understood yet, but the "accretion"
that is discussed in that article has to do with galactic collisions,
not runaway black holes, and _definitelly_ not due to extraterrestrial
intervention .

--
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