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Engineering newsletter

> If we use self reproducing robots, a chip-backery should be on board anyway.

No, each of the robots would be able to make chips on their own, the process 
isn't all that different than making solar cells.  Of Course, if they can 
make the chips they need, then the ones we need should be no problem.

> Kelly writes:
> >Judging from the fact they work harder at maintaining there lowtech comune
> >life style then I do my high tech style, I'm not sure about your
> >comparison.

But Kelly, the reason _you_ don't have to work so hard to maintain your 
life, is because many other people (millions and millions) have 
specialized and are suppling the things you need.  since Most of the 
Amish do their own Work (ie they grow their own food, repair their own 
equipment) the analogy is not fair.

> >The military is probably a better example.  They need rugged equipment, and
> >keep it for decades with limited upgrades.  But sooner or later it wears
> >out and has to be thrown away.

Actually, The military is a lousy example, they too are specialized, and 
if they weren't training how to fight, they would have plenty of time to 
build and repair whatever they needed.

> >The weight estimates were from the old stanford study.  which used mixed
> >soil and hydro farming.  (Hydro isn't that light, I mean water is heavy
> >too.)
> That water you need always, even if you use frozen food.

In fact, you would have less water in a hydroponics system than you would 
have in frozen food.

Let me take the example of carrots (simply because i happen to have a 
seed packet right here "Royal Chantenay", length about 5-6 inches, width 
about 2.5 inches)  Assuming a crew of 1024, each of whom eats an average 
of three carrots a day, and a planting to harvest time of 72 days (right 
off the seed package) allowing 18 days for equipment down time, we find 
that each crewmember needs about 11 feet of carrots (planted 1/2 inch 
apart, 3 * 90 / 24 carrots per foot) 

If the trays are three inches wide, and 9 inches deep, and they are 
stacked about two feet apart, then we can put 16 trays side-by-side, and 
stack four levels high (1st level at 0 feet, 2nd level at 2 feet, etc.)
then one "stack" feeds 64 crewmembers and we will need 16 stacks to feed 
the whole crew.  The volume of the "carrot Room" allowing 4 feet at the 
end of each row, and 2.5 feet between stacks, and placing the water pumps 
in the 2 feet below the floor level, will be:

(2.5 +(16*2)+2.5)*8*15=4440 ft^3 about 126 m^3

the volume of each tray would be 3726 in^3 for a total volume of 3.82E6 
in^3 or about 2208 ft^3 assuming another 292 ft^3 for pumps, lines etc, 
that gives 2500 ft^3 of water (about 71 m^3) which weighs about 1.5E5 lbs or 
71600 kg at any one time. Let's assume another 29000 Kg for equip 
(surely an overstatement, even Kelly must see that) and the total is 1E6 
kg for all the fresh carrots you can eat (provided you only eat about 3 a 

Now let's see how many carrots we need to put in frozen storage:
1024 *3 * 365 * 20 years = 2.2E 7 carrots (this already goes beyond the 
mass limit) now let's see how much space we need, assuming these stored 
carrots are grown special for us, in that they are rectangular right 
prisms 6 inches long, and 2 inches to a side, we find that each carrot 
takes up 24 in^3 or a total of 3.1E5 ft^3 (about 8800 m^3) this weighs about 
8.8 E6 kg

The warehouse takes eight times the mass, about seventy times the floor 
space, yeilds smaller portions (24 Cu in vs about 37 Cu in for fresh grown)
and the carrots will get progressively worse as time goes on for the 
stored ones.(can you say 20 year freezer burn - brrr) and if the mission 
goes beyond twenty years, you have to switch to freeze dried.

I don't believe this treatment would work for every food, for example, 
corn would probably be better stored than grown.  but potatoes would 
probably be best if  grown. same with lettuce, tomatoes, Cucumbers, or 
any other plant with a large food to non-food ratio.

I think i can make the same argument for chickens, and perhaps algea 
eating fish like tiapalia, but cows and pigs would be a definite out.  (I 
still think we should carry a few as breeding stock just in case we do 
get stuck in the target system, or decide to colonize it.  Animals might 
just be able to survive cryonic sleep by then, and any breeding stock 
should be stored as frozen and only revived if needed 

Please also note the following side benefit to growing our food.  it 
makes oxygen.  not enough to do without the mechanical scrubbers, but 
every little bit helps.  Also note that it takes less energy to grow the 
food than to accelerate the extra stored stuff to cruising speed (and if 
we don't hit .99 C, then Kelly needs even more storage space)

This should end the farm vs warehouse debate unless a flaw can be found 
in my calculations (always a distinct possibility)