Kalpana one

the nice thing about light in space, is that it can go a long ways
with little attenuation. it would be possible for the mirror to be
several miles away and still be aimed at the proper spot. Ive not
been able to find it on the net, but years ago, i heard about
something the Japanese had come up with. it was called a sunflower.
what it did was absorb the sunlight into a mixture of gasses, that
then sent a laser like beam comprised up of all the visible light
spectrum, though a light bundle. the light from these bundles could
be separated into many different rooms and into many different
floors. at that time they were using glass fiber optics, which could
send the light for miles. similar but cheaper systems using plastic
are suppose to be available for homes next year. these use plastic
fibers, which unfortunately can only carry the light for a few dozen
yards. light fibers are lighter, and more flexible than metal cables
used to carry electricity. they are also smaller and are more
resistant to problems caused by radiation.

--- In spacesettlers@yahoogroups.com, Al Globus wrote:
>
> At 12:49 PM 5/18/2006, you wrote:
> >why would it have to be attached. a mirror of that size could focus
>
> One of the things Kalpana One tries to stay away from is large, co-
orbiting
> pieces of hardware that may collide with the colony. Basically, I
don't
> like catestrophic failure modes in active systems. I prefer minute
to
> minute survival to depend on passive systems, because they screw up
less.
>
> That said, as someone noted, the exterior hull of Kalpana One is
about big
> enough. One could cover most of it with light collectors and
direct them
> to the interior, at least in principle, although I doubt light
pipes are as
> easy to work with as electrical cables -- but I might be wrong.
You need
> some body-mounted solar cells for emergency power.
>
> >the light in to a receptor at the center of one end. light pipes
are
> >basically glass tubes (several different methods of doing this)
that
> >carry the light along the path you chose. if the mirror is
frequency
> >specific to the visible light spectrum (meaning it only reflects
> >those frequency, and appears to be clear glass to all others), it
> >would not increase the heat of the station. the most likely method
of
> >doing this is to have bundles of fiber-optics that can be split up
> >to send each fiber to its proper destination. when it arrives it
> >enters a different type tube, one that radiates the light outwards
> >though out its length. or it can exist the fiber in a point light
> >source style, similar to light bulbs.
> >
> >one advantage of this system is that the light can be turned on and
> >off with easy, simply by blocking one end or the other. or it can
be
> >redirected in to another area for its uses.
> >
> >another advantage is that glass blocks ultraviolet radiation,
> >something that has been found to be detrimental to both animals and
> >plants. plants that are raised under sunlight with the ultraviolet
> >radiation block are bigger and less bitter than normal ones.
> >
> >another advantage is that it requires little structure, being
mostly
> >plastic.
> >
> >--- In spacesettlers@yahoogroups.com, Al Globus wrote:
> > >
> > > The primary reason light pipes were not used on Kalpana One is
> >because none
> > > of us were familiar with the technology.
> > >
> > > Here's a quick analysis:
> > >
> > > Kalpana One agriculture assumes 50m^2 per person for high
intensity
> > > agriculture (continuous sunlight, optimal atmosphere, etc.).
For
> >5,000
> > > people that works out to 250,000m^2 of plants. Assuming you
need
> >full
> > > sunlight (probably right within a factor of 2), this means
> >250,000m^2 of
> > > collection -- or a square 500 m on a side.
> > >
> > > Kalpana One's thermal design requires that the axis of the
cylinder
> >be
> > > aligned with the solar system's north-south axis. Furthermore,
the
> >hull
> > > exterior rotates at 2 rpm.
> > >
> > > I don't know how one could attach a 500m on-a-side solar
collector,
> >or even
> > > something half that size, to Kalpana One and keep it pointed at
the
> >sun.
> > >
> > > Anyone else have a good idea?
> > >
> > > At 06:46 PM 4/27/2006, you wrote:
> > > >I couldn't find a publication date on this. Does anyone know?
> > > >We might invite the writers of the paper here to discuss it and
> >answer
> > > >our questions.
> > > >
> > > >Ralph wrote
> > > > >>... its a shame to use artificial light for crop raising
when
> > > > >>theres so much natural sunlight. Agricultural is by far you
> > > > >>main power requirement. A way around this is to attach solar
> > > > >>collectors to the outside of the colony's hull and divert
the
> > > > >>sunlight into the agricultural areas with fiber optics.
> > > >
> > > >It does seem strange to allow sunlight into the habitable
areas,
> >but
> > > >use artificial light for agronomy. I wonder why was this was
> >chosen?
> > > >Also, I can't see how sunlight enters the habitable area; From
the
> > > >endcaps which are parallel to the sunlight's incoming
direction,
> >with
> > > >no mirrors?
> > > > With no light pipes or directed lighting, we must assume
that all
> > > >lighting in the inner low-G decks is artificial. Again, with
light
> > > >pipes, sunlight can be brought in anywhere, with no moving
parts.
> > > >It'd be interesting to see a study of the relative mass and
cost of
> > > >conventional electric lighting and light pipes for different
> > > >applications.
> > > >
> > > >Al Globus wrote:
> > > > > The exterior of the hull is rotating at 2rmp, giving you 1g
> > > > >away from the colony. Of course, as you move away from the
> > > > >hull the force becomes greater.
> > > >
> > > >Understood. Was this intended to rebut Ralph's suggestion for
> >exterior
> > > >light collectors? Sure, they'd be under outward pull, but they
> >could be
> > > >much smaller than the huge "petals" of O'Neill's Island 3.
> > > > One reason the Kalpana 1 designers might not like it is the
need