Once We Have A Self Sustaining Mars Colony - Then What?

On Tuesday, December 20, 2016 at 8:06:49 AM UTC+13, Fred J. McCall wrote:
bob haller wrote:


wonder what laser beams from space could do to our atmosphere?


Nothing.

Correct, particularly if the areal intensity is well below breakdown energy..

http://www.dtic.mil/dtic/tr/fulltext/u2/a133211.pdf

You need between 1 billion watts/cm2 and100 billion watts/cm2 depending on wavelength. Sunlight arrives at the top of the atmosphere at 136.8 milliwatts/cm2. There's a big range of power levels in there that don't cause any problem whatever!

Companies are using something on the order of 10,000 Watts/cm2 to beam power reliably and safely through optical fibers, light pipes and open atmosphere to efficiently regenerate power remotely with very light weight and compact systems;

http://lasermotive.com
https://www.youtube.com/watch?v=8hhv9Cu98us

Other companies are beaming on the order of 100 million watts/cm2 to beam power reliably and safely through the atmosphere and then concentrate it to break down levels to produce direct propulsive effects

http://www.lightcrafttechnologies.com
https://www.youtube.com/watch?v=KtH-SxqdtaA




just wait till a aiming problem or isis hacker redirects the beam into a weapon


You probably believe nuclear reactors can be made to explode like
bombs, too.


Beam steering in both Lasermotive and Lightcraft system use conjugate optics. Such system require the receiver generate a tracking beam that interacts physically with the optics of the transmitter in a way that sends energy back to the receiver. This is called phase conjugate reflection.

There is no way known to hack this. The tracking or reference beam is also modulated to identify the user so that people are billed for their power use. Modulation of power beam and reference beam also provide for broadband communications between the receiver and transmitter.

https://www.youtube.com/watch?v=gAy39ErqV34

https://www.youtube.com/watch?v=iHWIZsIBj3Q

--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine

On Wednesday, December 21, 2016 at 10:37:25 AM UTC+13, Fred J. McCall wrote:
William Mook wrote:

On Tuesday, December 20, 2016 at 9:29:12 AM UTC+13, Fred J. McCall wrote:
William Mook wrote:

On Monday, December 19, 2016 at 4:20:10 PM UTC+13, Fred J. McCall wrote:
Jonathan wrote:


When fossil fuel costs become excessive then
a truly useful commodity like space solar power
can become practical and the free markets will
have a new reason to build large structures
in space.


It's cheaper to build your solar power plant down here. Again, the
cost of lifting all that stuff from Earth in the first place makes
space-based solar far too expensive. Hell, Earth-based solar is too
expensive right now and space-based costs at least an order of
magnitude more.

And why would a solar power satellite require people?


Inflatable concentrators that focus light on to thin disk solar pumped lasers that use conjugate optics to beam energy reliably and safely to Earth - produce 22 kW of useable power on the ground per kg of payload at GEO.. A Falcon Heavy puts 18 tons into GEO sufficient to produce 400 MW of power continuously. The satellite costs $110 million. The Launch $90 million - $200 million altogether. At $0.11 per kWh a 400 MW power satellite operating 8,766 hours per year generats $385 million per year in revenue.


At the price point you give an SPS doesn't produce anything.

Yes it does.


Only if someone gifts the whole thing to you.

No, the cost is shown to scale at 22 kW per kg on orbit. At current costs of construction and launch this is $2,200 per kg - so we're getting 10 watts per $1 - or $0.10 per watt of capacity. So, with a 40 year life each watt generates 350.64 kWh. With no discount rate, this is 1/35th of a cent per kWh. With a 12% discount rate this is 1.4 cents per kWh. So, selling power at 11.4 cents per kWh earns the innovators 10 cents per kWh whilst paying the folks who finance the hardware (once demonstrated) superb long-term returns.


Prices
for SPS power are up around $3 or so, not 11 cents.

Considerable profit is earned at $0.11 per kWh when care is taken to use shorter wavelengths in the visible part of the spectrum, reducing optics and beam steering, and if concentrating thin film devices are used to reduce mass.


Bull****.

No its not.

See "Space-Based Solar Power As an Opportunity for
Strategic Security", Report to the Director, National Security Space
Office.

I have looked at that. It is available here;

http://www.nss.org/settlement/ssp/library/nsso.htm

Page 7 looks at the structure they assumed to compute their costs;

They assume 1000 W/kg for primary power production and 35% conversion efficiency. They produce ELECTRICAL power on orbit and convert that to microwave energy at 8.8 GHz with 80% efficiency - which they then use a phased array to beam back to Earth. This scales the system and enforces a particular price point and project size.

An 8.8 GHz system has a 34 mm wavelength. The distance from GEO to the equator is 35.768 megameters. The distance from GEO to the poles is 42.164 megameters. The Airy disk size of a spot the larger distance away is;

Airy Diameter = 42.164 * 10^6 * 1.22 * lambda / Diameter of dish.
Airy Diameter * Dish Diameter =169752.264

Making the diameters equal means we take the square root; 412 meter diameter receiver and transmitter in space. Increasing the diameter of the receiver lowers the diameter (and weight and cost) of the transmitter.


My analysis is available here;

http://bobkrone.com/node/120

I make a few different assumptions;

(1) I use 1,064 Nm as the longest power transfer wavelength
(2) I produce laser light directly from sunlight at 65% efficiency
(3) I receive laser light with bandgap matched photovoltaics with 90% efficiency
(4) I use a single inflatable concentrator in conjunction with a thin disk solar pumped laser
(5) I use circulating gases within the inflatable concentrator to cool the laser
(6) I use conjugate optics to direct the beam
(7) I use modulated laser energy to communicate with receivers

This provides major reduction in orbiting mass and permits compact receivers that may be installed without major ground infrastructure. Both radically reduce costs because I get 22,000 per kg. This is 22x better and so instead of $3 per watt its $3/22 per watt - or 13.64 cents per watt. Now, there are other cost savings as well in my system, due to ground station improvements and other factors - which get us down to $0.10 per watt mentioned previously.

The wavelength reduction alone reduces the size of the transmitting device from 412 meters to 7.4 meters for this all optical system.

Using a 1600x concentration ratio, which is a 40x reduction in diameter, the thin disk wafer is illuminated by a 296 meter diameter thin film concentrator. With a 65% conversion efficiency at the laser and 90% conversion efficiency through the beaming and ground station power conversion, this satellite delivers 55 megawatts continuously from orbit to receivers anywhere on Earth where the satellite is visible. The satellite itself masses 2,500 kg. Launch cost is $2.5 million. Construction cost is $3.0 million.

A Falcon heavy puts up 54,400 kg into LEO. This is 22 of the satellites described above. They are equipped with MEMS based solar powered ion engines - that boost them from LEO to GEO and beyond and provide 40 years of useful life by maintaining orientation and orbit once achieved. $55 million for launch costs. $66 million construction costs. Another $29 million development costs. A satellite every 18 degrees with two spares - provide a grand total of 1.2 GW continuously anywhere on Earth. The spares orbit in a slightly lower orbit that completes one revolution around the Earth every 20 hours. So, that they constantly outpace the 'fixed' satellites and complete a revolution of Earth every week. They provide spare power when they're in the sky, and they easily replace any satellite that must be taken out of the system and returned to a repair orbit.

Now a 296 meter diameter concentrator consists of 68,814 square meters of collector area. 75% of the mass is in the collector and with 3x the projected area dedicated to the oblate spheroid thin film we have 9 grams per square meter of collector surface. The balance of the system, 1250 kg, is allocated to the 43 square meter thin disk laser. That's 29 kg per square meter. 2.9 grams per sq cm.

1.2 GW of power deliver 10.6 billion kWh per year. When sold at $0.114 per kWh $1.2 billion per year is earned from $150 million invested.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

On Wednesday, December 14, 2016 at 6:29:57 PM UTC+13, JF Mezei wrote:
On 2016-12-13 00:28, Fred J. McCall wrote:

Orbital mechanics - learn some. EVERYTHING is an orbit. You need to
cancel enough orbital velocity to fall into the Sun. Otherwise,
you're going to loop around it.

Can't you "aim" the elliptical orbit such that the object passes close
enough to the sun's "atmosphere" to get slowed down at perigee such that
after a few orbits, it goes too deep inside the sun to come back out ?

The change in velocity to move from a circular orbit 1 astronomical unit (149,500,000 km) from the Sun to have a perihelion equal to the sun's radius (347,500 km) is not much difference between that and cancelling out the speed altogether (perihelion the centre of the sun). This is given by Vis Viva equation


dV = Vo - Vt

Vo = orbital velocity
Vt = transfer velocity
dV = delta vee (change in speed)

Vt = SQRT( 2/r - 1/a )

Where r= radius
a = semi-major axis.

Vo = SQRT( 2/r - 1/a) where a=r for a circular orbit.

So, if we do things in terms of astronomical units, or AU we have

14.5 million km = 1.00 AU
0.3475 million km = 1/430 = 0.00232441

Now that's perihelion. So, the major axis is 1 + 0.00232441 = 1.00232441.. And the semi-major axis is one half that or a = 0.501162207

Vo= SQRT(2/1-1/1) = 1
Vt = SQRT(2/1 -1/0.501162207) = 0.068103221

The semi-major axis for a perihelion of 0 is 0.5

Vt' = SQRT(2/1-1/0.5) = 0

Now we can convert these figures to km/sec by noting that a circle with a radius of 1 AU has a circumference of 939.336 million km and the Earth takes 1 year or 31,557,600 seconds to complete one orbit. Dividing the time into the distance obtains the speed of

939.336 / 31.5576 = 29.766 km/sec.

So, multiplying this figure by 0.681 obtains 2.027 km/sec. This means that we have a change in speed or delta vee of;

dV = 29.766 - 2.027 = 27.739 km/sec

Subtracting zero from this speed - which is the change that's needed to drop directly into the sun - makes only a 2.027 km/sec difference!

Now, since the 2.027 km/sec gives us a perihelion that assures us of complete annihilation in the first pass, its only a slightly higher perihelion that let's us skip off the solar atmosphere and take up a less energetic second pass. Let's be generous and say that is 10% more or 35,000 km higher up in the solar corona. A perihelion of 382,500 km instead of a perihelion of 347,500 km. This changes the 2.027 km/sec to 2.127 km/sec - which means we must subtract 27.639 km/sec. A DIFFERENCE OF 0.1 km/sec (223 mph)


If sending dangerous garbage to the great big solar system incinerator
won't work, there is little chance that any mining of planets would.

Garbage is dangerous relative to what?

Country--- 2007 2008 2009 2010 2011 2012 2013 2014 2015
Kazakhstan 6637 8521 14020 17803 19451 21317 22451 23127 23800
Canada--- 9476 9000 10173 9783 9145 8999 9331 9134 13325
Australia-- 8611 8430 7982 5900 5983 6991 6350 5001 5654
Niger----- 3153 3032 3243 4198 4351 4667 4518 4057 4116
Russia--- 3413 3521 3564 3562 2993 2872 3135 2990 3055
Namibia-- 2879 4366 4626 4496 3258 4495 4323 3255 2993
Uzbekistan 2320 2338 2429 2400 2500 2400 2400 2400 2385
China (est) 712 769 750 827 885 1500 1500 1500 1616
USA-------- 1654 1430 1453 1660 1537 1596 1792 1919 1256
Ukraine (est) 846 800 840 850 890 960 922 926 1200
South Africa 539 655 563 583 582 465 531 573 393
India (est) 270 271 290 400 400 385 385 385 385
Czech Republ 306 263 258 254 229 228 215 193 155
Romania (est) 77 77 75 77 77 90 77 77 77
Pakistan (est) 45 45 50 45 45 45 45 45 45
Brazil (est) 299 330 345 148 265 326 192 55 40
France---- 4 5 8 7 6 3 5 3 2
Germany--- 41 0 0 8 51 50 27 33 0
Malawi 104 670 846 1101 1132 369 0
Total world 41,282 43,764 50,772 53,671 53,493 58,489 59,331 56,041 60,496
tonnes U3O8 48 683 51 611 59 875 63 295 63 084 68 976 69,969 66,089 71,343
percentage of world demand* 64% 68% 78% 78% 85% 86% 92% 85% 90%

The radioactivity generated by the production

Company tonnes U %
KazAtomProm 12681 21
Cameco------------ 10926 18
Areva-------------- 9368 15
ARMZ - Uranium One 7849 13
CNNC & CGN------- 3303 5
BHP Billiton 3161 5
Rio Tinto 2757 5
Navoi 2385 4
Paladin 1435 2
Other 6631 11
Total 60,496 100%

tonnes U percentage of world
Australia 1,706,100 29%
Kazakhstan 679,300 12%
Russia 505,900 9%
Canada 493,900 8%
Niger 404,900 7%
Namibia 382,800 6%
South Africa 338,100 6%
Brazil 276,100 5%
USA-- 207,400 4%
China 199,100 4%
Mongolia 141,500 2%
Ukraine 117,700 2%
Uzbekistan 91,300 2%
Botswana 68,800 1%
Tanzania 58,500 1%
Jordan 40,000 1%
Other 191,500 3%
World total 5,902,900 100%

0.72% of the total uranium in the world is naturally fissile U235. The fissioning of an atom of uranium-235 in the reactor of a nuclear power plant produces two to three neutrons, and these neutrons can be absorbed by uranium-238 to produce plutonium-239 and other isotopes. Plutonium-239 can also absorb neutrons and fission along with the uranium-235 in a reactor.

The radioactive byproducts from even 5.9 million tons of radioactive waste is nothing compared to the radiation produced by the Sun.

http://onlinelibrary.wiley.com/doi/1...04087/abstract

Neutron flux is 30 neutrons per square meter per second. That means the entire sun produces 5.636x10^22 neutrons per second.

Alpha ray and beta ray fluxes are comparable

ftp://space.mit.edu/pub/plasma/publi...withthumbs.pdf

As are X-rays.

Nothing we do is especially dangerous as far as the solar system is concerned. It is only non-optimal for us and the biosphere. That's why energy production on Mars will be vastly less costly than on Earth.

The only possibility is some very rare "unubtainium" metal found in
abundance in some other planet (lets call it Pandora) where small
quantities are worth much more than the huge transportation costs. Not
gonna happen anytime soon.

You have no idea WHY you believe transport costs MUST be "huge" or even what that means. The fact is, for three months out of every 26 months an object on Mars projected at a speed of 6.3 km/sec or less from the surface in the right direction, will find its way to Earth. Use a magnetic mass driver at 20,000 gees (which is the acceleration given to shells by the rail gun known as Blitzer already built by General Atomics and already in test by the USN, it takes 19.8 GJ/MT - gigajoules per metric ton - to ship products from Mars to Earth. At 20 GW mass driver operating at 30 rounds per second - sends 'shells' of 33 kg each over this period. 7.9 million metric tons of raw material in the three month period, every 2.15 years. This is 3.7 million tons per year.

1,000 of these cannons operating at automated mining sites throughout Mars could supply 8 billion people with raw materials at a rate that permits every one of those 8 billion people to live at US levels of consumption of those materials.

Self assembling swarms of robots in self guided shells, could skip off the Earth's atmosphere, interact with the moon, and come into GEO above Earth, and self assemble into a solar power satellite. A similar operation could build massive space stations in polar orbit above the Earth along a sunrise sunset orbit - that grew food and delivered it on demand to anyone within 3 hours before and after sunrise and sunset twice a day.

Each person within the USA consumes 2.7 tons of materials per year excluding sand and gravel. 8.0 tons of materials including sand and gravel.

443 kg - Steel per person
180 kg - Aluminum per person
139 kg - Plastics per person
6 kg - Copper per person
3 kg - Zinc per person
0.0228 kg - Titanium per person

World---- per person Item

3,322.50 443 Steel
1,350.00 180 Aluminum
1,042.50 139 Plastics
52.50 7 Lime
45.00 6 Copper
22.50 3 Zinc
0.17 0.0228 Titanium

5,835.17 778.02 Total

Annual consumption of major materials that are easily extracted from Martian soil or air is given in the table above. The total production necessary to allow 7.5 billion persons to consume at US levels is shown.

12,545.62 million tons are dispatched every Synodic Period. This means that for a three month period every 2.15 years 1,590.19 metric tons of material is dispatched from Mars at up to 6.3 km/sec. Accelerations of 21,000 gees - 200,000 m/sec/sec - over a 99.3 meter length - means that 30 payloads per second are dispatched. So, 54 mass drivers each capable of projecting one ton payloads off world. Each mass driver consumes 595.35 GW of power. All 54 consume 32.15 TW of power during synodic period. About twice what humanity uses on a continuous basis. This requires the consumption of 2.32 kg/sec of Uranium in a 71% efficient combined cycle - MHD/Brayton - engine operating at Extreme High Temperature. Dividing this among 54 mass drivers, this is 1.42 grams per payload! Or 42.86 grams per second per mass driver.

Now, a Lithium Deuteride nuclear pulse unit - that produces 1.77 Giga-Newtons of thrust generates 32.1 TW of power during its operation when using propellant to lower exhaust speed to 20 km/sec. This same unit uses 119 grams per second of Lithium-6 Deuteride, which has the added benefit of no long term radiation by products.

A flight system that consists of four engines of the type described here, attached to a 235 meter long airframe that is capable of lifting 100,000 tons, in addition to 44,000 tons of propellant and 22,000 tons of structure - provides significant capacity to send payloads between worlds. 14,000 tons from Earth to Mars. 100,000 tons Mars to Earth.

However, ONE of the four engines on the system, produces enough power to operate ALL 54 rail guns. Alternatively, ONE rail gun that launched 54 ton payloads at 21,000 gees - could fit in the length of one ship. So, a mining operation that produced materials over a 23 month period would then spend another 3 months launching it all back to Earth. Operating only one engine without inert propellant 'burning' 940 tons of lithium-6 deuteride in an aneutronic nuclear reaction over a three month period. Between launch periods the system operates to reduce and mine metals from surrounding ores.

William Mook wrote:

Each person within the USA consumes 2.7 tons of materials per year excluding sand and gravel. 8.0 tons of materials including sand and gravel.

443 kg - Steel per person
180 kg - Aluminum per person
139 kg - Plastics per person
6 kg - Copper per person
3 kg - Zinc per person
0.0228 kg - Titanium per person


I'm pretty sure I'm not consuming anything like those levels. Please
provide a cite for the preceding numbers. Note that metals typically
are not 'consumed' because they get recycled into new things. I
suspect Mook is ignoring that as well as just taking total national
'consumption' and dividing by population, which has nothing to do with
much of anything (think exports, etc).

snip MookMarsMaundering


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

On Thursday, December 22, 2016 at 4:08:43 AM UTC+13, Fred J. McCall wrote:
William Mook wrote:

Each person within the USA consumes 2.7 tons of materials per year excluding sand and gravel. 8.0 tons of materials including sand and gravel.

443 kg - Steel per person
180 kg - Aluminum per person
139 kg - Plastics per person
6 kg - Copper per person
3 kg - Zinc per person
0.0228 kg - Titanium per person


I'm pretty sure I'm not consuming anything like those levels.

Not personally perhaps. It depends on your income. However, understand that beyond income dependence industry must build things like big tractors and harvesters out of steel to grow your bread. Industry must build big freaking dump trucks and shovels to get you coal, that adds to your consumption.. If you consume more than the average bear, more of that steel consumption goes to you.

The numbers are from the USGS - just type in "USGS steel consumption USA" into your search engine of choice, and you get back

https://minerals.usgs.gov/minerals/p.../iron_&_steel/

Then, you click the most recent data ... and in this case youfind the apparent steel consumption is 110 million tons per year. Divide that by the population of the USA to get a per person consumption of 344.8 kg per year. Multiply by 128% to get the upper quartile of consumption. That is, those with higher incomes consume more stuff. So, if you want to produce wealthier populations - the top 1% - you must have that multiplier.


Please
provide a cite for the preceding numbers.

The USGS is very careful to identify all these factors. You have to go over each one.

Note that metals typically
are not 'consumed' because they get recycled into new things.

True, and the USGS accounts for that. If you are building steel mills on Mars and want to transform life on Earth with an abundance of raw materials that make life better for all, then you cannot recycle what isn't there. That meanas you've got to ship more actually, to build up the inventory - and then scale back to Earth. Of course, at the same time, there are emerging off world population centres that will be building up their consumptions, by creating space colonies and the like.

I
suspect Mook is ignoring that as well as just taking total national
'consumption' and dividing by population, which has nothing to do with
much of anything (think exports, etc).

Exports and Imports are accounted for in the consumption figures reported by the USGS. Also the bulk of humanity is not consuming steel or any of these other materials at anywhere the rate of the USA. So, if we were to provide sufficient steel say, to allow everyone everywhere to consume at the level of a HNWI ($30 million or more) today, there is not an inventory to recycle, so that inventory has to accumulate, so there is a characteristic production curve when that happens. That's where the 28% comes from.

On Thursday, December 15, 2016 at 5:09:15 PM UTC+13, Fred J. McCall wrote:
JF Mezei wrote:

On 2016-12-14 06:25, Jeff Findley wrote:

People that propose this somehow assume that once you reach "earth
escape" velocity that you'll magically fall right into the sun as long
as you "escape" in the right direction.


I realize that the garbage ship will be in the sun's orbit after
escaping earth.


And yet you don't seem to.


But consider Apollo returning from the moon. It doesn't need delta-V to
land on earth because it is aimed such that its elliptical orbit scapes
earth's atmosphere which then gives it the delta-V needed to end orbit.


What? I suspect you are not saying what you mean clearly, because the
preceding makes no sense.


So I am not advocating that the garbage ship lower its circular orbit, I
am advocating that it transform its circular orbit into highly
elliptical one. And in that case, would the delta-V requirement be
significantly lower ?


That is precisely the delta-V requirement everyone is referring to. It
is an order of magnitude larger than the change required to go
anywhere else.



Please stop hand waving and DO THE MATH! Lucky for you since this is
the 21st century, I'm willing to bet that if you did a bit of Google
searching, you'd find an "orbit calculator"


My confusion:

I understand de-orbiting from ISS. You fire de-orbit engines against
your orbital speed which not only reduces orbital energy, but puts you
into elliptical orbit with perigee sufficiently inside atmpsphere to
continue to slow you down.


Essentially correct. Most of the delta-V required to hit Earth (which
you are already orbiting very close to) is provided by atmospheric
braking. Remember, ISS is so close to Earth that it must periodically
reboost due to atmospheric drag.


But when Apollo came back from the moon, it did not fire engines against
Earth orbital velocity, as a ship does to drop out of orbit from ISS, it
accelerated toward the Earth, and once past laGrange, let Earth
accelerate it. Very little delta-V was involved, it merely had to
ensure it got to the right place at right moment to scrape the
atmosphere just right to slow it down enough to kill what would be an
elliptical orbit.


Of course it did. That's how it got out of the orbit the Moon is in.
This 'straight line' stuff you keep doing in your head is WRONG.


I assume that as Apollo got accelerated towards earth, its orbital
velocity around earth accelerated (since altitude dropped). Yet, it
still managed to aim itself to scrape the atmosphere on first pass
instead of endlessly spinning in an elliptical orbit that never touches
the upper reaches of atmosphere.


Not how it worked.


So (in simple words for my simple mind), why can't a garbage truck be
sent to the sun in the same way that Apollo returned to earth ?


It can. That way just isn't what you think it is and it has a delta-V
requirement on the order of 29 kps plus whatever it takes to get into
LEO first.

Several people have told you that it doesn't work the way you think it
does and yet you still want to insist that it does.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

The Earth completes an orbit around the sun in a year, and the orbital radius is 149.5 million km approximately. So the circumference of a circle that big is 939.3 million km. There are 31.5576 million seconds in a year so the average speed of the Earth is 29.766 km/sec. Anything sitting on Earth must escape Earth's gravity and then have an excess velocity of this amount in order to zero out its motion relative to the Sun, so that it can fall INTO the Sun. That's

V = SQRT( 11.19^2 + 29.77^2) = 31.80 km/sec

Now, with a practical rocket, you have air drag and gravity loss. This typically adds 1.2 km/sec - so you have to have enough capacity in your rocket to achieve 33.00 km/sec to fall into the sun.

Now, if you graze the outer atmosphere of the sun, and let the sun slow you down without falling right into the sun, you can save some delta vee. How much? Well, instead of zeroing out your speed, you can retain about 2.07 km/sec speed at Earth's orbit. This reduces your required delta vee to less than 31 km/sec. Here the orbit loops around the far side of the Sun (relative to where it was launched from Earth) and loops into a radius equal to the Sun's radius - half its diameter of 695,000 km. That means an object 149.5 million km away must fall down to 0.3475 million km. 1/430th its original distance! That's pretty close to zero! You're saving only 2 km/sec out of 33 km/sec. Grazing the sun at an altitude where you have several passes, saves only 0.01 km/sec or less - since you're varying perihelion by a very small amount compared to 149.5 million km where you started.

Now, if you boost out to Jupiter first, and then use a slingshot maneuver to zip around Jupiter and let it shoot your payload out with zero velocity relative to the Sun, you can reduce your hyperbolic excess velocity for a trans Jovian orbit. We need a hyperbolic excess velocity of 10.6 km/sec.

http://ccar.colorado.edu/asen5050/pr.../analysis1.htm

This means that if we start on the Earth's surface we require 15.4 km/sec. Now this is substantially LESS than the two DIRECT orbits. In fact, solar probes use this path to getting near the sun.

* * *

William Mook wrote:

On Thursday, December 22, 2016 at 4:08:43 AM UTC+13, Fred J. McCall wrote:
William Mook wrote:

Each person within the USA consumes 2.7 tons of materials per year excluding sand and gravel. 8.0 tons of materials including sand and gravel.

443 kg - Steel per person
180 kg - Aluminum per person
139 kg - Plastics per person
6 kg - Copper per person
3 kg - Zinc per person
0.0228 kg - Titanium per person


I'm pretty sure I'm not consuming anything like those levels.

Not personally perhaps. It depends on your income. However, understand that beyond income dependence industry must build things like big tractors and harvesters out of steel to grow your bread. Industry must build big freaking dump trucks and shovels to get you coal, that adds to your consumption. If you consume more than the average bear, more of that steel consumption goes to you.


I understand all that (probably better than you) and it gives a false
picture.


The numbers are from the USGS - just type in "USGS steel consumption USA" into your search engine of choice, and you get back

https://minerals.usgs.gov/minerals/p.../iron_&_steel/

Then, you click the most recent data ... and in this case youfind the apparent steel consumption is 110 million tons per year. Divide that by the population of the USA to get a per person consumption of 344.8 kg per year. Multiply by 128% to get the upper quartile of consumption. That is, those with higher incomes consume more stuff. So, if you want to produce wealthier populations - the top 1% - you must have that multiplier.


In other words, the numbers are arrived at exactly as I speculated
below.


Please
provide a cite for the preceding numbers.

The USGS is very careful to identify all these factors. You have to go over each one.

Note that metals typically
are not 'consumed' because they get recycled into new things.

True, and the USGS accounts for that. If you are building steel mills on Mars and want to transform life on Earth with an abundance of raw materials that make life better for all, then you cannot recycle what isn't there. That meanas you've got to ship more actually, to build up the inventory - and then scale back to Earth. Of course, at the same time, there are emerging off world population centres that will be building up their consumptions, by creating space colonies and the like.


Actually they account for some and don't account for others. A lot of
the steel 'consumed' in any given year is produced from (you guessed
it) recycled steal that was 'consumed' in previous years. Your
'importing' steel from Mars to Earth is, well, merely silly.


I
suspect Mook is ignoring that as well as just taking total national
'consumption' and dividing by population, which has nothing to do with
much of anything (think exports, etc).

Exports and Imports are accounted for in the consumption figures reported by the USGS. Also the bulk of humanity is not consuming steel or any of these other materials at anywhere the rate of the USA. So, if we were to provide sufficient steel say, to allow everyone everywhere to consume at the level of a HNWI ($30 million or more) today, there is not an inventory to recycle, so that inventory has to accumulate, so there is a characteristic production curve when that happens. That's where the 28% comes from.


And just how much of the steel 'consumed' is made out of scrap steel?


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

Mars has a lot going for it, but is it the best?

Transfer W/m2 AU Siderial Synodic Object

0.709 589.16 1.524 1.881 2.135 Mars
1.090 245.30 2.362 3.629 1.380 Vesta
1.292 178.82 2.766 4.600 1.278 Ceres

Earthbound
a Vp Vt dV dV kps
1.262 0.810 0.721 0.089 2.648 Mars
1.681 0.651 0.502 0.149 4.430 Vesta
1.883 0.601 0.438 0.163 4.855 Ceres

Outbound
Vt dV dV kps
1.099 0.099 2.944 Mars
1.185 0.185 5.518 Vesta
1.212 0.212 6.311 Ceres

Vesc dV surface
5.027 5.682 Mars
0.360 4.444 Vesta
0.510 4.882 Ceres

So, a mine on Mars can ship material to Earth with a rail gun for about 3 months every 25.62 months. A mine on Vesta can ship material to Earth with a rail gun for about 4 months every 16.56 months. A mine on Ceres can ship material to Earth with a rail gun for about 5 months every 15.34 months!

It takes 8.51 months for materials departing Mars to arrive at Earth. It takes 13.07 months for materials departing Vesta to arrive at Earth. It takes 15.50 months for materials departing Ceres to arrive at Earth.

Objects fired from Mars arrive at 11.57 km/sec at Earth. Objecs fired from Vesta arrive with a speed of 12.48 km/sec. Objects fired from Ceres arrive with a speed of 12.85 km/sec. For comparison the Space Shuttle deorbits from 7.9 km/sec and Apollo re-entered the Earth's atmosphere falling from the Moon at 10.85 km/sec. Recently however, Juno probe to Jupiter successfully entered Jovian space after slowing down from 55.56 km/sec to enter orbit around Jupiter.

http://www.theglobeandmail.com/techn...ticle30753296/

The next dates these objects could send stuff to Earth and when they arrive are;

Mars

Conjunction Arrival
Aug 03 2019 Apr 17 2020
Sep 20 2021 Jun 04 2022
Nov 08 2023 Jul 23 2024

Vesta

Conjunction Arrival
Feb 27 2019 Mar 31 2020
Jul 15 2020 Aug 17 2021
Dec 01 2021 Jan 03 2023
Apr 19 2023 May 21 2024

Ceres

Conjunction Arrival
Oct 04 2018 Jan 19 2020
Jan 14 2020 Apr 30 2021
Apr 24 2021 Aug 09 2022
Aug 05 2022 Nov 19 2023

So off-world mines and farms would be arriving on these dates from these locations

Ceres Jan 19 2020
Vesta Mar 31 2020
Mars Apr 17 2020
Ceres Apr 30 2021
Vesta Aug 17 2021
Mars Jun 04 2022
Ceres Aug 09 2022
Vesta Jan 03 2023
Ceres Nov 19 2023
Vesta May 21 2024
Mars July 23 2024

So, knowing the capacity of each planetary mining system, and its ability to ship off-world, we can use these conjunction dates to determine volumes and predict effect on pricing, or schedule terrestrial construction programmes to take advantage of changes in supply.

Of course, the conjunction dates are also dates emmigres depart for these objects and the arrival dates of cargo are the dates they arrive at their objective.

On 12/20/2016 6:37 PM, William Mook wrote:
On Wednesday, December 21, 2016 at 10:32:18 AM UTC+13, Fred J. McCall wrote:
William Mook wrote:

On Tuesday, December 20, 2016 at 2:27:33 PM UTC+13, Jonathan wrote:
On 12/18/2016 9:17 PM, William Mook wrote:

There are insufficient resources on Earth today to sustain everyone
at a high living standard. So, we must either establish a repressive
governance world wide to allocate those limited resources in a
sustainable way, or we must reduce populations, or we must reduce living
standards to do as you say. All three avenues are being pursued at the
present time.

I've been hearing that for a long time, it's a myth.

Its not a myth. You've heard it for a long time because its true.




No it isn't, every reputable institution agrees
world poverty has plummeted in the last 30 years
or so as free markets have expanded, especially
since the Internet. While population has nearly
doubled, that completely destroys your idea
that the Earth can't supply our needs.

It's our societal structures that are flawed
and create the problems you cite. I agree
completely however that power and wealth
are far too concentrated and that causes
economic misery.

The power law shows what the relationship between
top and bottom...should be...in a healthy naturally
evolving system. And the old 80-20 law holds where
20% of the population should hold 80% of the
power or wealth. In the US we're not even close
to that, and a better distribution of wealth
is badly needed.

But that inequity has nothing at all to do
with scarcity of minerals or other natural
resources. It has to do with corrupt and
dictatorial systems that need more democracy
and freedom.

If you put the democracy index next to the
GDP of the same nations, the correlation
is crystal clear, that dictatorships of
any kind, political, military or corrupt
capitalist, is the source of misery.

Mining Mars for iron for crying out loud
when it costs less than 5 cents a pound
is just plain lunacy.


OCTOBER 7, 2015 11:58AM
The Dramatic Decline in World Poverty
By IAN V�SQUEZ SHARE

This week the World Bank released new data on world poverty,
and projects it to fall to a record low of 9.6 percent in 2015.
The graph below shows the dramatic decline of global poverty
over the past few decades.

The drop in poverty also coincides with a significant increase
in global economic freedom, beginning with China’s reforms
some 35 years ago and the globalization that followed the
collapse of central planning in the late 1980s and early 1990s.
As we celebrate this achievement and strive for further
progress, we should not lose sight of the central role
that voluntary exchange, freedom of choice, competition
and protection of property play in ending privation.
https://www.cato.org/blog/dramatic-d...-world-poverty






All extreme scarcity is artificially induced and maintained by those who benefit from that scarcity. All dictators are backed by the money interests who benefit from the existence of those dictators. Saddam Hussein was backed by the USA to scare up the price of crude whenever it lagged.




Saddam Hussein? The US just helped crushed world oil prices down
by half by fracking like crazy. Your anecdotes from the past
are cheap debating tactics, history is very long and complicated.

Show us one industry /today/ not cheap trick vague examples
from the immense fog of history where your conspiracy theory
holds in your opinion, and lets debate that.

I can go back into the past and find anecdotes where dictators
have caused incredible harm too. For instance here's a nice
summary of the largest blood-lettings of the last century.

And you'll see America did NOT start....any of them.


30 Worst Atrocities of the 20th Century
The Hemoclysm
http://users.erols.com/mwhite28/atrox.htm


Dictatorships started them all, and you can't come up with
a SINGLE EXAMPLE when two functioning democracies went
to war with each other, NOT ONE (of note).

Yet history is strewn with examples of dictatorships starting
or going to war with each other. To any rational, or unbiased
mind (hint) the problem and solution is easy to see.

More free market democracies, and I mean legitimate and honest
free market democracies. Not just in name only or corrupt
as hell.



So Mookie insists out one side of his mouth that there are not enough
resources on Earth

True. The limited resources on Earth relative to the resources off world limits the amount that can be usefully invested without excessive environmental disruption.




Name one resource that can be profitably mined from another
celestial body and would ease the plight of humanity.

Name one?

The moon has plenty of gravel, Mars plenty of iron, big deal
the Earth has plenty of both. Don't even try the H-3 nonsense.
If it costsASA $6 billion and 10 years to return a few pounds
from Mars your pie-in-the-sky cost estimates can't be taken
seriously.




while out of the other he claims that scarcity is a
plot.

True. Those who manage the capital use technocratic means to deploy that capital and they take the aforementioned limits to growth into account in that deployment.

Phew, what a loony!

Well, only if you're foolish enough to read the two statements as mutually exclusive. They are not.

It takes capital to create wealth. Since capital is restricted to an elite class of individuals and economic speech is restricted only to that class, and all follow a strict technocratic logic, which is demonstrably the case today, that class limits their invesments in ways that ehnace their power and influence in the face of natural limits to growth.

[Yeah, I chopped out a thousand lines or so of MookSpew.]

Yeah, the behaviour of someone who is in denial - when they're not being angry.. lol.

The five stages of loss,

denial,
anger,
bargaining,
depression and
acceptance

These are a part of the framework that makes up our learning to live with things we lose.

You've lost because your entire world is built on a fantasy. When you can you ignore that fact, when you cannot you get angry. You have yet to have reality seep into your consciousness.




You're into stats, put these two lists side by side
and what do you see? A child could see free market
democracies and prosperity go hand-in-hand, while
the despots of the world create the hell-holes
of humanity. If you can't accept the relationship
then it's you that's in denial, and denial of
clear facts.


http://www.yabiladi.com/img/content/...Index-2015.pdf

https://en.wikipedia.org/wiki/List_o...y_GDP_(nominal)



Nature shows us how to live in a sustainable and
beautiful way. We need to learn the lessons of nature
which my hobby of the fairly new field of self organizing
systems, or complexity science show us.

Stability and prosperity, or a naturally evolving
society that mimics nature and it's wonderful
attributes requires two primary properties.

The 'rules of operation' must be strictly followed
and 'freedom of interaction' must be strictly
enforced.

Rules and freedom.

For instance the US constitution (rules)
and our Bill of Rights (freedom)

When those two opposing behaviors are
critically interacting, then the system
will....self organize and evolve.

The reason the US leads the world is we have
the best combination of population size
and democracy. There are better democracies
and there are larger populations.

But only America has both a large population
and high level of freedom. That is the formula
for success.



--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."

-- Heinrich Heine


"HE preached upon “breadth� till it argued him narrow,—
The broad are too broad to define:
And of “truth� until it proclaimed him a liar,—
The truth never flaunted a sign.

Simplicity fled from his counterfeit presence 5
As gold the pyrites would shun.
What confusion would cover the innocent Jesus
To meet so enabled a man!"


E Dickinson



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