Solar-pumped laser power transmission, a way to dramaticallydecrease launch costs?

On Apr 22, 3:47*pm, Brad Guth wrote:
On Apr 22, 5:39*am, William Mook wrote:

On Apr 21, 2:52*pm, Brad Guth wrote:

On Apr 21, 8:40*am, William Mook wrote:

On Apr 18, 1:56*pm, Brad Guth wrote:

On Apr 16, 4:33*am, William Mook wrote:

On Apr 7, 10:01*pm, Brad Guth wrote:

It all sounds perfectly doable, and without a great deal of R&D.

I especially like this spiral welding pipe machine:
*http://zencharn.en.alibaba.com/produ...346/spiral_wel...

A sphere forming and welding machine would certainly be terrific. *How
about we invent a metallic plasma spray, used to create extremely
tough spheres, with as thin of shell as necessary?

*~ BG

Plasma spray is but one technique to achieve the end you seek

http://nsmwww.eng.ohio-state.edu/htt...g/wiki/Stereol...

A stereolithography system using electroplating produces metal parts.
These parts must be heat treated to be work hardened. *But, they're
very interesting!

http://www.circuitree.com/Articles/F...a14b3d7d7010Vg...

An electrolyte bath containing metal ions in solution feeds a
'printhead' that moves in X,Y and Z coordinates, and plates metal onto
a 'base' from solution. *Since the metal is conductive, the 'base' can
be the part itself, allowing complex structures to be formed, very
similar to those produced by stereolithography.

In the extreme vacuum of Selene L1 (at the very least worth 3e-18
bar), whereas it seems plasma spray or ion transfers of pure alloys
into becoming perfect spheres, *as such would achieve by far the most
idealistic end results at the least cost. *Such spheres could be as
formed thin or robust and even a km radii if need be, because size,
volume or mass has extremely little affect.

*~ BG

NASA did a study on this back in the 60s. *Large pressure vessels are
easy to form in vacuum, and zero gee, regardless of location. *One
major issue is work hardening which is addressed by method of cooling
- quenching - the metal as its formed.

That "work hardening" factor doesn't seem all that insurmountable,
because lasers of mostly IR could keep whatever material or new
products at whatever ideal temperature we like, for as long as it
takes. *As well as according to Apollo 13, it's nearly always
cryogenic between Earth and our moon, so therefore cooling or
quenching whatever should not be any problem.

*~ BG

Right researchers encountered problems in the R&D with metal being too
soft and fixed the softness problem by work hardening the metal upon
forming. *Researchers developed a technique of quenching which
provided the mechanical deformation needed to work harden the metal
when formed by rapidly cooling the metal once formed. *Cooling not
heating is the problem in vacuum.

Not according to our Apollo era, whereas instead cabin heating was a
big problem. *So, how come they (namely A13) nearly froze to death?

Because the Command Module was designed to maintain room temperatures
with 2 kilowatts of electrical equipment operating continuously. The
Lunar Module was designed to maintain room temperatures with 3
kilowatts of electrical equipment operating continuously. So,
connected together, the two systems were set up to maintain room
temperature while operating 5 kW of electrical equipment on board.

Without an oxygen supply those power systems were shut down in the
Command Module and the Lunar Module's systems were operated at only 5
watts to extend the duration of the fuel cell supply to make it back
to Earth along a lunar free return trajectory.

With the same radiator areas and mass flow off ship, and only 1/10th
the electrical load, without that heat source there was a heat
imbalance which reduced temperatures to the 50 degree range.

http://www.spaceaholic.com/apollo_artifacts.htm

*Quenching is a rate of cooling
problem and rate of cooling in a vacuum is a function of the fourth
power of temperature by Stephan Boltzman. *Metal solids are not hot
enough to cool by radiation fast enough, which is a re-statement of
the original problem. *So, you can't do direct forming of work
hardened metals in a vacuum. *You can quench metals formed in vacuum
by spraying something on the metal that then rapidly evaporates to
vacuum. *Something like water.

Water is explosive at 3e-18 bar (perhaps 3e-21 bar within Selene L1
would be a whole lot worse),

You obviously have no direct experience with these things. A rapid
reduction in pressure causes an explosive reaction with water. Water
moving through pores from 1 atm to 0 atm ices up and evaporates
carrying away heat.

http://www.astronautix.com/craft/a7l.htm
http://www.techbriefs.com/content/view/701/34/

perhaps even nasty if discharged as
cryogenic ice as long as that sun shines and the IR comes off that
physically dark moon and/or from Earth. *How about using cryogenic
sodium or ceramic powders?

This is an absolutely idiotic statement Brad. The difference between
1e-17 and 0 is as nothing when compared to 1 atm. So, 3e-21 makes
absolutely no difference when compares to 3e-18 when compared to 1
atm.

It seems artificial shades could buy as much cooling as you like.

Not when you're in a vacuum generating kilowatts of power, eating
food, and exercising.

How the heck did fused lunar basalt manage to get so hard?

You have absolutely no clue about anything you talk about. These
statements prove it. How can someone care so much about a thing and
not trouble themselves to learn something about it?

How about forming composite spheres as near entirely those of CVD
carbonado (black diamond of 490 GPa) with a thin coating of whatever
alloy inside/outside?


Totally non-sequitor. I'm sorry I tried to engage you in useful
conversation.


This was the same sort of problem encountered by manufacturers of
swords. *Sword manufacturers had to heat the sword and plunge the
sword in a vat of water to cool it rapidly.

Safe storing of 99.5% h2o2 doesn't require any special alloy sphere
work-hardening. *In fact softer alloys might seem a whole lot better.

Ah, I see we've uncovered another entire realm of knowledge you are
totally ignorant of.

Storing of liquid hydrocarbons (such as Mook synfuel from coal)
doesn't require any special alloy work-hardening.

You're missing the point sir.

Insulating of large spheres doesn't require any special alloy or other
kinds of molecular substance work-hardening, not that extremely
thermal cycling can't be accommodated.

??? You have missed several points by this time - and I don't have
the patience to unravel the Rubick's cube of connected errors you have
made.

*~ BG

Stephan Boltzmann gives how fast something can radiate away energy per
square meter

J/m2 = 5.67e-8 * T^4

So, a 6.5 cm ball in space that absorbs all the energy falling on it
near 1 AU from the sun absorbs no more than 4.55 watts. This same
ball must rise to a temperature of 279 K to radiate away heat at the
same rate it arrives. Even if the ball were perfectly reflective and
generated more than 5 watts of energy internally, it would overheat.
Evaporation of water or some similar compound would carry away heat
more quickly, as long as the supply of material lasted.

On May 25, 8:42*pm, William Mook wrote:
Stephan Boltzmann gives how fast something can radiate away energy per
square meter

* *J/m2 = 5.67e-8 * T^4

So, a 6.5 cm ball in space that absorbs all the energy falling on it
near 1 AU from the sun absorbs no more than 4.55 watts. *This same
ball must rise to a temperature of 279 K to radiate away heat at the
same rate it arrives. *Even if the ball were perfectly reflective and
generated more than 5 watts of energy internally, it would overheat.
Evaporation of water or some similar compound would carry away heat
more quickly, as long as the supply of material lasted.

Correct. It seems Japan, China and India were each intentionally
misinformed as to properly dealing with all that continuous solar plus
secondary lunar IR heat, and perhaps not made aware as to the extent
of hot sodium which also surrounds our moon/Selene.

Perhaps using a supply of HTP (98% h2o2) would be a good coolant, as
well as a viable source of energy as long as the supply of material
lasted.

How about using a conventional closed cycle form of Stirling
refrigeration/cooling?

How about their using solar and lunar IR shades, in order to block out
the sun and moon?

~ BG