SETI again

im not sure where you got the idea that the oort cloud spread out
that far into interstellar space. when i was reading about the object
they are calling the 10th planet, it was discussing the fact that
that was very near the point where solar gravity would no longer keep
the planets in orbit. there was some discussion on wheither or not it
was really a rogue object that happen to be passing though the fringe
of our solar system. orbits around the sun dont extend as far as one
light year, let alone two.

--- In spacesettlers@yahoogroups.com, "Lucio de Souza Coelho"
wrote:
>
> On 7/28/06, Robert wrote:
> (...)
> > problem with this is that the space between stars has few comet
and
> > such
> (...)
>
> Certainly the density is lower than inside the Solar System, but
even
> though it is a perfectly adequate density for space habitats. The
Oort
> cloud is estimated to have *trillions* of comets, separated by
> interplanetary-like distances - which means that it would take
months
> or at most years for a habitat to hop from one to another - and
> extending as far as two light years - which means that our own
> cometary cloud may touch those of other systems. Also, relatively
> recent discoveries regarding brown dwarfs and rogue planets point
out
> that they are probably far more numerous than stars, and between
here
> and Alpha Centauri you may find several (or even many) of them
(though