Sunday, June 20, 2010

If The Windmill-Powered Casino on Greylock Never Gets Built

A band of solar cells all around the moon? Beaming energy in the form of microwaves at the earth? A Lunatic idea. And Murphy's law would seem to dictate that we'd want to design a system so that, even if the beam were deliberately pointed at Manhattan, no one would suffer much inconvenience or heating (let alone instant, smoking death).

But it's an idea that just might work, someday. At any rate, it's great that the modern world can fund and support NASA and academic (and even Japanese construction firm) scientists working on theoretically possible methods of achieving such a sustainable power source.

Why solar power in space and not on Earth?

Why the moon and not in closer, easier to get to, orbit?
1) Crowded space in the lowest orbits and in geosynchronous orbit.

2) Panels in space would considerably shade Earth (but that might be a good thing if global warming becomes a problem).

3) Cost. Cost. Cost.
Theoretically, at least, it could be cheaper to do it on the moon than closer to Earth.

That's because even low-earth orbit is very expensive to obtain (at least $2,000 per pound of payload to low orbit), and geosynchronous orbit costs about 5 times as much. And costs are not going to fall much until or unless we have a cabled space elevator (for geosynchronous).

It is, course, much more work to bring things and people to the moon. (We haven't done it recently, making cost estimates speculative.)

The moon is 250,000 miles away, versus ~200 miles for a rather low orbit and 22,000 miles for geosynchronous orbit; but bringing the material to the moon would not be proportionately more expensive, as we see with geosynchronous orbit being 100 times higher, but only 5 times more expensive, than low orbit. (That's because the cost of getting a mass to low orbit is more set by the need to obtain 18,000 MPH orbital velocity, than by the need to merely lift it 200 miles.)

More important, the Moon, unlike space, is filled with stuff. The trick is to design a system of mines and factories so that a modest amount of materials, robots and people sent to the moon can be be used to mine, smelt and manufacture that stuff into the materials needed to build a massive belt of solar cells all the way around the Moon's equator. (Half of the cells would be in the daylight at any given time; the power would be sent to the main Moon base, which position would always be facing the Earth.)

Consider one way to bootstrap materials: instead of shipping all the water that the base would need, ship hydrogen, which could be used to grab the oxygen from various moon rocks, producing water weighing 9 times as much as the brought hydrogen, and simultaneously producing metals and other elements (e.g., aluminum, titanium, silicon) of perhaps twice the weight of the hydrogen.

With silicon for solar cells, aluminum for electric transmission lines, and titanium for structural elements, you've got essentially everything you need to manufacture your enormous belt of solar cells.

Once the moon base was making more solar power than needed to maintain itself and keep its humans alive, this power could be used to separate minerals without much need for additional resources from Earth. Then a growing proportion of the growing power supply could be sent to Earth by some form of electromagnetic radiation, such as light (laser) or microwaves. Lasers sound rather dangerous to me, whereas there ought to be some radio or microwave frequency that could be picked up by giant antennas, but which would mostly bounce off the Earth if they missed the antenna.

While the Moon transmitter would need only one location (since the moon always keeps the same face to us), the Earth would have to have receivers in three locations, with each getting energy for about 1/3 of each 25-hour "day" when the moon was overhead. The energy received at each would in part be delivered as electricity for immediate use, and in part be stored, perhaps as synthesized fuels such as hydrogen or natural gas (used to generate electricity for the 2/3 of the time that no Moon energy would be arriving), or it could be delivered around the Earth by intercontinental electric transmission line.

So, there are a few problems yet to solve... But this concept is the first I've ever heard that justifies the manned space program as more than just bread and circuses, but without the bread.

Friday, June 11, 2010

The Circle Game

Sometimes I'm amazed at what my children know, and sometimes I'm amazed at what they don't know.

I attended a middle-school graduation ceremony today. The younger students, including my 8-year-old daughter, made up a chorus. Their last song was, as the music teacher informed us, a real tear-jerker -- "The Circle Game" by Joni Mitchell, with the chorus:

And the seasons they go round and round
And the painted ponies go up and down
We're captive on the carousel of time
We can't return we can only look
Behind from where we came
And go round and round and round
In the circle game

Women were wiping their eyes, and I was probably close to sobbing as well. The kids performed quite nicely, but I sensed that they had little idea of what the song was about. I asked my daughter later, "why do you think the song was sad?" Her answer: "because a man is stuck on a carousel?"

Friday, June 04, 2010

NY Times Says Circulation Holding Up to WSJ Assault

That's the headline in a Bloomberg story of June 4 based on an interview with New York Times CEO Janet Robinson.

"We are definitely not seeing any effect in regard to the circulation," Robinson is quoted. But if you read to paragraph 7 of the story, you learn that "The New York Times’s nationwide circulation fell 8.5% to 951,063 in the six months through March, while circulation at the Journal, which includes paying Internet readers, rose less than 1% to 2.09 million, data from the Audit Bureau of Circulations show."

How can such a juxtaposition earn the headline "NY Times Says Circulation Holding Up to WSJ Assault" instead of something like "NY Times Official Puts Desperate Spin on Plummeting Circulation Figures"? (Which would itself be a pretty soft way of calling her a liar.)

It's part of a pattern which could make left- and right-wing talking heads on Fox News look objective. Take a similar article from April 26, which includes this:

Diane McNulty, a Times spokeswoman, attributed the lost print readership to a focus on “quality circulation and high retention rates,” saying the newspaper has kept most readers who have subscribed for two years or more. In an e-mail to employees today, New York Times Co. Chief Executive Officer Janet Robinson and Chairman Arthur Sulzberger Jr. said that “readers and advertisers are very loyal.”

The Journal “will soon discover the intensity of that dedication,” they wrote.

So they haven't this year lost more than 50% of "readers who have subscribed for two years or more"? Is there anyone who would guess that things could be worse than that?

The Times and sister-paper Boston Globe, like many other newspapers, are going down the tubes; demonstrating that they are run by fantasists certainly can't help matters, even if they have Bloomberg headline writers and the Obama Administration eager to bail them out.