[Frank]

$this->bbcode_second_pass_quote('JohnDenver', '')$this->bbcode_second_pass_quote('Frank', 'S')pace mirrors?

We've already got more than enough sunlight falling on the planet every day to meet all our needs -

[Doly]

I wonder what is the EROEI of putting a mirror in space, considering the enormous amount of energy needed to get anything on orbit.

[Devil]

Easy to answer that question.

When there are thick clouds, it is identical to a PV installation, zero.

[0mar]

or even less!

[eric_b]

$this->bbcode_second_pass_quote('Devil', 'E')asy to answer that question.

When there are thick clouds, it is identical to a PV installation, zero.

[bentstrider]

$this->bbcode_second_pass_quote('eric_b', 'A')s an amateur astronomer, already it's hard enough to find
a good dark sky in north america. Between the increasing amounts
of haze and air pollution, and all the light pollution from streetlights
at night, I doubt most people under 20 have ever seen the milky
way, which can be bright enough to cast a shadow under a truly
dark sky.Those bright mirrors would also severly fuck with the sensitive
eyes of nocturnal animals, which are already on the defensive.
If such a thing were ever launched, I'd probably have to
go jihadi and shoot it down down for aesthetic reasons alone.
-Eric B

[JohnDenver]

$this->bbcode_second_pass_quote('eric_b', 'F')orget about the technical problems with this idea.

[eric_b]

$this->bbcode_second_pass_quote('JohnDenver', '
')
(...)

There shouldn't be much harm in blotting something out which most people have never seen anyway. I'm sure many municipalities would be delighted to have new, brightly lit "art" in their skies to spice things up a bit, and save energy. It might even be a good tourist attraction. It's just a question of developing a good marketing campaign to sell it to the public.

[Liamj]

Another wonder of space exploration

Perchlorate found in breast milk / Discovery fuels debate over pollution from rocket launches.
http://www.nature.com/news/2005/050221/ ... 21-13.html

[Devil]

I feel, using the test of reasonableness, that there is unlikely to be cause and effect between the use of perchlorate in rocket fuels and the increase of perchlorates in tissues.

Firstly, they are used only in solid fuel rockets, such as the shuttle boosters. The fuel is a mixture of a rubbery compound, aluminium powder and ammonium perchlorate and looks and feels like a dark red rubber. Ammonium perchlorate, NH4ClO4, is the oxidant and it decomposes at temperatures of the order of 100°C. As all the fuel in a rocket, during combustion, by far exceeds this temperature, there is no way that any perchlorate ions could escape, before, during or after firing.

Secondly, perchlorates are the least stable of all the chlorates and uncontrolled contact with any organic matter can result in spontaneous combustion. At the best, it will be reduced to chloride very fast indeed. The perchlorate ion has a free lifetime of seconds or minutes in contact with organic matter. As its salts are deliquescent, it is very mobile in nature. This implies that the ions must be sequestered by some means or other, if they are to survive any length of time.

Thirdly, do they have uses other than in rocket boosters? The answer is yes! The major use is in fireworks, where coloured fire is produced by a mixture of sodium perchlorate and metallic salts, such as strontium for red. As the conditions are much less controlled, I would say, as a gut feeling, that this would be a much more likely source of the anion, generalised over a large area on 4 July in the USA. It is also possible that some "designer explosives" may contain some, but I have no information on that. Finally, it is conceivable that chlorate (ClO3-) weedkillers may contain a very small quantity of ClO4- anions as an impurity, although I have no data on this. If this speculation is correct, then it could be scattered on the ground.

Coming back to the shuttle boosters, in the unlikely event of their being responsible, there would be two regions where the effect could be marked, N. Utah, where they are manufactured and the fuel is mixed and cast, and E. Florida, where they are launched. If the perchlorate loading in breast milk were significantly higher in one or both of these two regions, then we may have a suspicion of cause and effect. But the study took samples from women in 18 states, implying uniformity, so this does not seem to be a likely cause.

[Liamj]

$this->bbcode_second_pass_quote('Devil', 'I') feel, using the test of reasonableness, that there is unlikely to be cause and effect between the use of perchlorate in rocket fuels and the increase of perchlorates in tissues.

[JohnDenver]

The Concept:



$this->bbcode_second_pass_quote('', 'I')t is technically and economically feasible to provide at least 100,000 GWe of solar electric energy from facilities on the Moon. The Lunar Solar Power (LSP) System can supply to Earth power that is independent of the biosphere and does not introduce CO2, ash, or other material wastes into the biosphere. Inexhaustible new net electrical energy provided by the LSP System enables the creation of new net material wealth on Earth that is decoupled from the biosphere. Given adequate clean electric power, humanity's material needs can be acquired from common resources and recycled without the use of depletable fuels [4, 5]. LSP power increases the ability of tomorrow's generations to meet tomorrow's needs, and enables humanity to move beyond simply attempting to sustain itself within the biosphere to nurturing the biosphere.

[Doly]

Why would the moon be any better than a satellite? When it comes to it, why would a satellite be any better than having solar panels on Earth?

[aahala]

(Ala Guiness commercial)

Moonbeams! BRILLIANT!

[Devil]

This is clearly for lunar-tics. It is just so bloody stupid as to be pathetic.

1. Everyone will agree that the same side of the moon faces the earth all the time ± a few degrees. Therefore, if such a station is put plonk in the centre of the disc we see, it is in darkness from decreasing half-moon to increasing half-moon. As there would be effective illumination for, say, 10 or 11 days per lunar cycle, what are we supposed to do for the remaining 17 or 18 days?

2. As the earth rotates under the moon, then only one continent (roughly) at a time can get power, say for a max of 8 hours/day, so the power converters on earth will not be operating for 16 hours/day. This assumes the transmitter on the moon is capable of orienting its beam to the required place with sufficient accuracy and then suddenly switch to the next one, taking into account all the wobbles and changes of refraction..

3. What would happen when solar storms saturate the receivers, even if it were possible?

4. What technology would you use for beaming the power to earth? We do not have anything that would allow the generation of a CW of more than a few hundred kW.

5. Who would do the necessary maintenance? How much would it cost? Remember there is no atmosphere, so the temperature excursions from full solar exposure to no solar exposure would be in the hundreds of degrees. The wear and tear would be extreme for anything supposed to last a month or two.

6. The capital cost would be even more astronomic than the moon itself and the energy required to put all the material and living quarters for the crew would literally be out of this world.

Think a little and get real before posting such bullshit.

[JohnDenver]

$this->bbcode_second_pass_quote('Doly', 'W')hy would the moon be any better than a satellite?

[Aaron]

Then how about selling advertising on the moon?

Great big neon tubes spelling out stuff visible from Earth.

We could get Mitsubishi to make a gigantic TV up there, and broadcast full video.

Imagine watching the Super bowl on the moon!

We could make a fortune on those commercials.

----------------------------------------------------------

I actually might have access to someone who could comment on this as an authority. As the former director for NASA's lunar colonization research program, it would be interesting to have his opinion.

I'll forward this and see what we get.

[JohnDenver]

$this->bbcode_second_pass_quote('Devil', 'T')his is clearly for lunar-tics. It is just so bloody stupid as to be pathetic.

[Mercani]

This is one of the most stupid energy generation method that I have ever heard!

JD, can you address Devil's points please?

How does that factory on the moon work? Do you drill moon for oil? or do you use solar power to construct mirrors?

[JohnDenver]

$this->bbcode_second_pass_quote('Aaron', 'I')magine watching the Super bowl on the moon!