How to build a PressuVessel?

From: tomexe [mailto:tomexe@...]

Why would the glass be too thick? Its SPACE. There is potentially
unlimited electrical power to melt the silica and the completed
prisims don't weigh anything.

This guy Zubrin, the more I hear of him
the more he sounds like a snake oil salesman, who just plays off of
peoples ignorance. So its huge, so what? No gravity, cheep power, it
doesnt matter if its huge...

It matters if his arguments hold sway in the space advocacy community
because he's made O'Neill's proposals look ridiculous by assuming glass 10
times thicker than anything O'Neill ever actually proposed.

However, what has me intrigued is that the thickness of glass which Zubrin
characterized as "prohibitively expensive" was a mere 10 cm. He was talking
specifically about raising crops, so I think he was probably taking into
account that plants can tolerate higher levels of radiation than we can.
The lunar studies Joe Russo was referring to were probably assuming the
necessity of reducing the cosmic ray flux to Earthly levels.

But even there, I have a hard time seeing why this can be accomplished with
about 6 feet thickness of slag, but require 40 feet of glass to do the same
job. I would expect the relative densities to be much closer than what that
would suggest.

You won't get any argument re your appraisal of Zubrin. What he's actually
doing is what logicians call the "appeal to incredulity".

Regards,

Mike Combs

From:
tomexe [mailto:tomexe@...]
Why would the glass be too thick? Its SPACE. There is potentially
unlimited electrical power to melt the silica and the completed
prisims don't weigh anything.

This guy Zubrin, the more I hear of him
the more he sounds like a snake oil salesman, who just plays off of
peoples ignorance. So its huge, so what? No gravity, cheep power, it
doesnt matter if its huge...
It matters if his arguments hold sway in the space advocacy community because he's made O'Neill's proposals look ridiculous by assuming glass 10 times thicker than anything O'Neill ever actually proposed.

However, what has me intrigued is that the thickness of glass which Zubrin characterized as "prohibitively expensive" was a mere 10 cm. He was talking specifically about raising crops, so I think he was probably taking into account that plants can tolerate higher levels of radiation than we can. The lunar studies Joe Russo was referring to were probably assuming the necessity of reducing the cosmic ray flux to Earthly levels.
But even there, I have a hard time seeing why this can be accomplished with about 6 feet thickness of slag, but require 40 feet of glass to do the same job. I would expect the relative densities to be much closer than what that would suggest.

You won't get any argument re your appraisal of Zubrin. What he's actually doing is what logicians call the "appeal to incredulity".

Regards,
Mike Combs