click here to see what this wise man says!
Posted on 11/17/2004 8:02:57 PM PST by Brett66
Brought back memories of when three of us in Unified talked to a propulsion professor about building a mini-jet engine. He was very dismissive - said "sure you can make a mini-jet engine - but you're compressor's gonna have to be the size of this desk here." Sorta like "If it ain't been built - can't be done".
P.S. Hope you meant "brass rat"
I'm not trying to win. I want to know if this will work or not. I would think that this could be modeled easily enough. I would hope that someone has done so.
15 psi at 25000 mph.
So the typical cargo, ice, would have to be encased in something akin to the space shuttle's large external fuel tank? This may not be entirely a problem, as I would want to also get large quantities of structural material into orbit.
Are you familiar with the fact that aluminum can be made to be repulsed in an alternating magnetic field? (similar to the response one gets from superconductive material -- magnetic mirroring)
Ideally, aluminum as an encasing and strengthening material would be helpful. I am rather concerned about the wastefulness of using large quantities of iron, when the asteroids would appear to be replete with it.
No, it doesn't work.
ET is about as thick as a dime, would be gone in 60 microseconds.
Barely Used Space Station - No Reserve!
You are bidding on a barely used Space Station - already in orbit - which can be used for a Bed & Breakfast, or a poet's retreat, or to operate illegal and truly offshore enterprises from - your choice. Item is posted with No Reserve and for the very low opening bid price of just $1!!
Item comes as is, and does not include supporting launch services, or operating infrastructure, which should add just a few odd billions at most. Don't delay - it's orbit might decay!!!
exactly
Make up any numbers you like, the results are the same.
Well, in the first place, I wouldn't use a dime's thickness.
Since the ablation would be concentrated at the front of the payload, I would attempt to minimize material losses there. However, since the payload is ice, ablation of the cargo is not necessarily a problem, as long as structural rigidity can be maintained for accurate downrange positioning.
Essentially, it is artillery in function. How big does the cannon need to be to launch a cylinder of ice into orbit? We'll make it that big.
One can reverse the calculation. A cylindrical asteroid of water-ice is coming into Earth's atmosphere at high speed. How big does it have to be for an appreciable fraction of its mass to survive to impact?
It may be useful to consider the purpose of this exercise. If "artillery shells" of ice can be reliably launched into predictable sub-orbital paths, it would be no more than an engineer's snowball fight to irrigate the desert. Any desert.
OK, everyone call me dumb. But isn't there a law that says that centrifigal force is the same at all points of a spinning object?
As the crawler starts up the tether isn't it pulling the counterweight into a lower orbit? Then as the crawler goes back down it will reduce the force of the tether on the counterweight and cause it to go back into the original orbit.
Clue offered. Crack the whip!
This problem of angular momentum (or coriolus acceleration)
is one that stuck out at me the very first time I read about this concept many years ago when it was being popularized by Arthur C. Clarke. I was surprised at the time that this issue simply was never raised by Clarke or any other science writers.
I thought maybe I had it wrong. It's good to see that there is someone else who noticed this rather fundamental flaw in the scheme.
Don't worry, it's impossible for something to orbit the flat earth anyhow. It would just fall back down to Earth!
The problem with tape hiss was never solved by digital encoding, but avoided in the same way that music playing off a CD avoids needle clicks/pops heard on LPs. A digital bitstream being read off a magnetic tape and decoded will not have any hiss. However, if you run the signal from the tape straight into an amplified speaker, you'll hear tape hiss...and no music.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.