Mars is kind of short of nitrogen

Mike Combs wrote:
"Sander Vesik" wrote in message
...

It appears to be bar far better to use solar batteries and artifical
lightning combined with hydroponics.

I could believe this if I could believe that on a square-mile to square-mile
comparison, solar panels and electric lights were comparable in price to
aluminized Mylar and glass.

covering square kilometers with thick layers of ultraclear glass so that you
both have radiation protection and not too bad light losses won't probably
be cheap either.

I'm quite sceptical of designs that have there be rolling fields of
agriculture hapenning inside O'Neill colonies - it seems like both not overly
thought out and very wasteful of space.


--


Regards,
Mike Combs
----------------------------------------------------------------------
We should ask, critically and with appeal to the numbers, whether the
best site for a growing advancing industrial society is Earth, the
Moon, Mars, some other planet, or somewhere else entirely.
Surprisingly, the answer will be inescapable - the best site is
"somewhere else entirely."

Gerard O'Neill - "The High Frontier"



--
Sander

+++ Out of cheese error +++

Sander Vesik wrote:
Mike Combs wrote:
"Sander Vesik" wrote in message
...

It appears to be bar far better to use solar batteries and artifical
lightning combined with hydroponics.

I could believe this if I could believe that on a square-mile to square-mile
comparison, solar panels and electric lights were comparable in price to
aluminized Mylar and glass.

covering square kilometers with thick layers of ultraclear glass so that you
both have radiation protection and not too bad light losses won't probably
be cheap either.

Then again, by complicating the mirror design a bit, you can pump all the
light through a hole that's radiologically negligable.
If you'r feeling really clever, you can even bounce it round using
mirrors once it gets inside, so that no radiation gets in.

Ian Stirling wrote:
Sander Vesik wrote:
Mike Combs wrote:
"Sander Vesik" wrote in message
...

It appears to be bar far better to use solar batteries and artifical
lightning combined with hydroponics.

I could believe this if I could believe that on a square-mile to square-mile
comparison, solar panels and electric lights were comparable in price to
aluminized Mylar and glass.

covering square kilometers with thick layers of ultraclear glass so that you
both have radiation protection and not too bad light losses won't probably
be cheap either.

Then again, by complicating the mirror design a bit, you can pump all the
light through a hole that's radiologically negligable.
If you'r feeling really clever, you can even bounce it round using
mirrors once it gets inside, so that no radiation gets in.


Sure - but now you are talking about lots of mirrors and complicated designs,
instead. I still favour "compact", hydroponics and artifical lighting based
design. While you could use mirrors in compact designs it will very fast start
looking pretty crazy.

I'm afraid I'm terribly bad at producing "viewgraphs" and well presesented
numbers - but I will try to get some of this stuff on the web soon.

--
Sander

+++ Out of cheese error +++

Sander Vesik wrote


covering square kilometers with thick layers of ultraclear glass so that you
both have radiation protection and not too bad light losses won't probably
be cheap either.

I'm quite sceptical of designs that have there be rolling fields of
agriculture hapenning inside O'Neill colonies - it seems like both not overly
thought out and very wasteful of space.

Yes.

What are the plants for? Mostly, to recycle CO2 and provide food. You might
also want a few to look pretty, or for gardens or parks.

But the food/ air crops don't need protection from radiation - you could
just grow them in, oh say big bubbles of clear plastic. Tie the bubbles on
pieces of string and put them out in the sun for a month, then bring them
back inside to harvest the food and air. You'd probably have to raise seed
seperately.

That would leave the expensive radiation-protected space for people.


--
Peter Fairbrother

Good grief folks; besides investing hundreds of billions, as in having
to import nearly everything into Mars (including body bags), if not
taking a trillion+ for the likes of Mars, plus at least another decade
as best, I do believe it's time (way past due) that you all refocused
a wee bit closer to home. There's been life on Venus (could still be
happening) and most certainly of whatever is left of life on Mars,
whereas all three of us being influenced if not entirely terraformed
by the likes of Sirius.

Another little thing; there essentially NO energy to being had on
Mars, but Venus has way more than it's fair share of energy.

This following rant is just another update, along with a link to the
most recent page that pertains mostly to Venus, but also reflects upon
Mars and of what Sirius has to do with Mars, Earth and Venus.

I'm still one of those nice guys that's all for getting onto the moon,
and the sooner the better, though it's become rather interesting that
official "spin" and "damage control" folks like "Gordon D. Pusch" and
perhaps yourself, that continually claim to know everything there is
to know, however besides your leaving out specifics for your side of
these arguments, you seem to be getting miffed about what's so easily
had upon our moon, as well as anything pertaining to Venus, and of now
anything pertaining to Sirius is supposedly off-topic. The prospect of
the LSE-CM/ISS utilizing the affordable basalt composite tether(s) has
also become too much for these folks.

I obviously can't do everything, nor can most common folks, though
others can certainly pitch in with whatever their expertise, as even
odd notions along with whatever mistakes is allowed, as long as those
mistakes are not of the sorts of intentional flak like I've been
receiving for the past three years.

The question often asked; "they (NASA/ESA) must be able to do
something" simply has gone answered, though as for their first-off
negative stance about nearly everything under the sun pretty much sums
up the sorts of "can do" or can't possibly do" issues as most of our
NASA/ESA folks see them; "where's the money?"

Too bad I'm not sufficiently rich nor polished at my saying "I told
you so" or perhaps "finders keepers", as I'd certainly have liked to
have involved others, along with at least matching funds, and to
insure the absolute fullest of credits on their behalf. As far as
"where's the money" goes, I believe this is a self enterprising
opportunity of folks simply doing whatever's right, as even if we
continue making our human mistakes, chances are that whomever survived
Venus is going to have something we need, and vice versa, and thereby
perhaps our resident warlord(s) can summarily take whatever from them,
or we might consider being nice and accommodating for a change, as
lord only knows, they might make their initial mistake of thinking
we're not so bad to deal with, as all we'll have to do is keep the
likes of Osama bin Laden from speaking with them, or perhaps even
those Dogon folks should be excluded, since they haven't developed the
necessary levels of greed and snookering to the degree that we've
managed through our in-your-face carnage-R-us policies.

What's needed are for these folks opposing just about everything under
the sun, to start telling us specifically why it's supposedly so damn
difficult or even impossible as to deliver a sufficient laser beam,
onto and thereby sufficiently penetrating those nighttime clouds of
Venus. Even placing a serious long distance laser packet on it's way
toward Sirius can't be impossible, especially with the 0.1 milliradian
and 100 MW class delivery of those two death-ray outfitted ABLs.

Then perhaps thay can also be informing us village idiots as to why
the likes of TRACE can't seem to image upon the nighttime portion of
Venus.

Another question that needs answers;
What's so damn hard, or even spendy about establishing a Venus L2
stationkeeping platform?

Venus style aerodynamics is almost too good to be true, so why not
simply place an interactive communications kiosk onto their tarmac?

Here's the latest deliveries upon "what's new and of what's hot", as
offering a little more of my three brain cells worth on behalf of
Sirius terraforming the likes of Mars, Earth and Venus.
http://guthvenus.tripod.com/gv-earth-venus.htm
http://guthvenus.tripod.com/gv-sirius-trek.htm

Calling Venus;
If you're perchance interested in the hot prospect of achieving
interplanetary communications, as for that quest I've added lots, if
not a little too much, into this following page;
http://guthvenus.tripod.com/gv-interplanetary.htm

BTW; There's still way more than a darn good chance of there being
other life of some sort existing on Venus:
http://guthvenus.tripod.com/gv-town.htm

Some good but difficult warlord readings: SADDAM HUSSEIN and The SAND
PIRATES
http://mittymax.com/Archive/0085-Sad...andPirates.htm

David Sereda (loads of honest ideas and notions upon UV energy), for
best impact on this one, you'll really need to barrow his video:
http://www.ufonasa.com

The latest round of insults to this Mars/Moon/Venus class action
injury:
http://guthvenus.tripod.com/gv-what-if.htm

Some other recent file updates:
http://guthvenus.tripod.com/moon-04.htm
http://guthvenus.tripod.com/gv-gwb-moon.htm
http://guthvenus.tripod.com/gv-illumination.htm
http://guthvenus.tripod.com/gv-moon-02.htm

Regards. Brad Guth / IEIS~GASA


lid (John Savard) wrote in message ...
but, as Robert Zubrin notes, it does seem to be the best place to set
up a colony.

However, are there any other alternatives that might be even more
attractive?

One of the objections Dr. Zubrin gives to O'Neill colonies is that a
mirror area comparable to the crop area is required for agriculture.
As it would seem to me that aluminized Mylar is easier to construct
than the *land area of the colony itself*, that seems to be an odd
objection.

But the mirror area could be smaller if the colony was closer to the
Sun.

Venus' atmosphere has about the same percentage of nitrogen in it as
Mars', but it is many times denser. A well-shielded O'Neill colony - I
have a design for one, shaped like a wine bottle, with a further
shielding slab out past the mirrors putting light down the neck of the
bottle, where the shielding doesn't rotate - in orbit about Venus
might have access to a good source of biomass feedstock. (Metal and
rock would be sent from the Moon.)

Since the gas giants have very deep gravity wells, comets and Pluto
seem to be the other potential non-terrestrial sources of nitrogen in
the Solar System.

John Savard
http://home.ecn.ab.ca/~jsavard/index.html

"Sander Vesik" wrote in message ...
John Savard wrote:

One of the objections Dr. Zubrin gives to O'Neill colonies is that a
mirror area comparable to the crop area is required for agriculture.
As it would seem to me that aluminized Mylar is easier to construct
than the *land area of the colony itself*, that seems to be an odd
objection.

It appears to be bar far better to use solar batteries and artifical
lightning combined with hydroponics.

"Lighting."

The problem is that with the efficiency of these, which is limited by
the laws of physics, you'll always lose at least around 80% of the
original energy by converting light to electricity and back.

Since the gas giants have very deep gravity wells, comets and Pluto
seem to be the other potential non-terrestrial sources of nitrogen in
the Solar System.

Remember Titan.

I think many regions of the outer Solar System will become sources of
volatiles and light elements for the inner planetary orbits. And
heavy elements will become the prime trading goods for the outer ones.
Once humanity splits into societies inhabiting many different worlds
then many will have what others need and vice versa.

It's gonna be interesting...



--
__ “A good leader knows when it’s best to ignore the __
('__` screams for help and focus on the bigger picture.� '__`)
//6(6; ©OOL mmiv :^)^\\
`\_-/ http://home.t-online.de/home/ulrich....lmann/redbaron \-_/'

In article ,
lid (John Savard) wrote:

but, as Robert Zubrin notes, it does seem to be the best place to set
up a colony.

All other factors (such as distance and travel time) being equal,
certainly so.

But those other factors are most decidedly NOT equal. It may still be a
great place to set up a colony one day, but definitely not the best
place to set up our *first* colony.

,------------------------------------------------------------------.
| Joseph J. Strout Check out the Mac Web Directory: |
| http://www.macwebdir.com |
`------------------------------------------------------------------'

In article ,
"Ool" wrote:

It appears to be bar far better to use solar batteries and artifical
lightning combined with hydroponics.

"Lighting."

The problem is that with the efficiency of these, which is limited by
the laws of physics, you'll always lose at least around 80% of the
original energy by converting light to electricity and back.

First: so what? Gather more energy. One of the primary points of
colonizing space is that energy is cheap and abundant.

Second: it doesn't even mean you need more light-gathering area (even
assuming solar power), because light in orbit is available 24/7 and at
much higher intensities than here on Earth.

Quick calculation: if we assume 20% efficiency for light-electricity,
and 55% efficiency for electricity-light (which is the current best
rate, in sulfer discharge lamps), the product is 11% efficiency.
Multiply by 7, for amount of sunlight available in GEO vs. the ground,
and you have 77% as much light available in this way as compared to
using the light directly.

But this does not take into account that the artificial light generated
might be more efficiently used for photosynthesis. Take that into
account, and I bet you could grow MORE crops per square meter of solar
panel than you could grow per square meter of dirt on Earth.

,------------------------------------------------------------------.
| Joseph J. Strout Check out the Mac Web Directory: |
| http://www.macwebdir.com |
`------------------------------------------------------------------'

lid (John Savard) wrote in message ...
but, as Robert Zubrin notes, it does seem to be the best place to set
up a colony.

However, are there any other alternatives that might be even more
attractive?

One of the objections Dr. Zubrin gives to O'Neill colonies is that a
mirror area comparable to the crop area is required for agriculture.
As it would seem to me that aluminized Mylar is easier to construct
than the *land area of the colony itself*, that seems to be an odd
objection.

That is about as stupid an objection as the rest of his objections,
which are only raised to push the case for Mars. The mirrors would
weigh less than the crop structure right out to Neptune.

But the mirror area could be smaller if the colony was closer to the
Sun.

Not worth it, since the mirror mass is trivial. Better to put them
close to Earth, within 3 days flight, where they can particpate in
Earth's economy.

Venus' atmosphere has about the same percentage of nitrogen in it as
Mars', but it is many times denser. A well-shielded O'Neill colony - I
have a design for one, shaped like a wine bottle, with a further
shielding slab out past the mirrors putting light down the neck of the
bottle, where the shielding doesn't rotate - in orbit about Venus
might have access to a good source of biomass feedstock. (Metal and
rock would be sent from the Moon.)

This is a good design, but a bigger challenge will be heat disipation
through the shield.

Since the gas giants have very deep gravity wells, comets and Pluto
seem to be the other potential non-terrestrial sources of nitrogen in
the Solar System.

Comets, and former comets, some of which have recently become NEOs.
They may well have ammonia deposits. It is also possible that the
lunar poles have frozen ammonia, though probably not enough for a few
O'Neill colonies. At worst, we'll need to go to the asteroid belt.

Medium term, it might be possible to scoop Nitrogren out of the
Earth's atmosphere. This wouldn't be enough for O'Neill colonies, but
would sufffice for large Torus stations).

John Savard
http://home.ecn.ab.ca/~jsavard/index.html

John Savard wrote:
but, as Robert Zubrin notes, it does seem to be the best place to set
up a colony.

However, are there any other alternatives that might be even more
attractive?

One of the objections Dr. Zubrin gives to O'Neill colonies is that a
mirror area comparable to the crop area is required for agriculture.
As it would seem to me that aluminized Mylar is easier to construct
than the *land area of the colony itself*, that seems to be an odd
objection.

You aren't the first (or the last, I imagine) to raise this point. There
are many things Zubrin says I disagree with. (Although I still admire
the man).


But the mirror area could be smaller if the colony was closer to the
Sun.

Venus' atmosphere has about the same percentage of nitrogen in it as
Mars', but it is many times denser. A well-shielded O'Neill colony - I
have a design for one, shaped like a wine bottle, with a further
shielding slab out past the mirrors putting light down the neck of the
bottle,

Described on this page?:
http://www.hypermaths.org/quadibloc/science/spaint.htm

You call your mirror system "Cassegrain"?
After the parabolic mirror concentrates it into a focus
it looks like a convex mirror redirects the converging rays
back into parallel rays.

My system is somewhat similar:
http://clowder.net/hop/railroad/ChengHo.html
But where you have a convex mirror redirecting converging rays to
parallel, I have a smaller parabolic mirror sharing the larger
parabolic's focus.

Also I have a 4th mirror that reflects the parallel rays onto the sides
of the cylindrical hab. It seems to me your system would also need such
a mirror as parallel rays would just pass through the bottle's neck and
land on disk at the bottom instead of illuminating the bottle walls. Or
am I missing something?

In my design the hab is built from asteroidal materials atop the north
pole of the asteroid. So the asteroid provides radiation shielding over
almost 2 pi steradians. The walls of the hab have a mixture of water and
dirt that I hope would be adequate radition shielding from those
directions. The the 4 mirrors (including the axial mirror) would shield
some from the top. The top is the most vulnerable radiation leak in this
colony, I believe.

In future drawings I plan to make 2 habs spinning in opposite directions
- one on the north and the other on the south pole. The net angular
momentum is zero and so the entire mass would be more manueverable. (I
stole this idea from Mike combs who has imagined two linked Bernal
spheres spinning in opposite directions. His structure would also have
zero net angular momentum)

Also in my colony the atmosphere doesn't fill the entire cylinder - just
a cylindrical shell. Less nitrogen would be needed.

here the shielding doesn't rotate - in orbit about Venus
might have access to a good source of biomass feedstock. (Metal and
rock would be sent from the Moon.)

Asteroids could also be a source of metal and rock.


Since the gas giants have very deep gravity wells, comets and Pluto
seem to be the other potential non-terrestrial sources of nitrogen in
the Solar System.

We still know very little about the composition of most asteroids.
Perhaps some have ammonia or other nitrogren compounds. Especially the
outer main belt and the Trojans.


John Savard
http://home.ecn.ab.ca/~jsavard/index.html


--
Hop David
http://clowder.net/hop/index.html