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Post by Apollo Gnomon on May 19, 2010 12:50:55 GMT -4
Seven days later and no answer. This must be a new definition of "soon" that I'm not aware of. I can't help contrasting this with what happened when I e-mailed Eric Jones with a question about Apollo 14. He answered the question the next day. Hagbard Celine wants us to be suspicious of NASA and its associates, but he is the one acting evasive. I'm famous for cutting people slack and giving benefit of doubt. Hagbard_Celine wasn't posting at Delusional Idiots forum in the intervening time, either. He's said he's a hospital porter. He probably works a crap shift and has a limited amount of time to visit his imaginary friends (us) during off-hours, and hopefully has something better to do on days off. In fact, this would also explain the rather shallow approach he's made to debating these things anyway - he doesn't have the volumes of time with a fresh mind that some of us do to just waste time debating nonsense with our invisible friends.
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Post by laurel on May 19, 2010 13:33:29 GMT -4
I understand what you're saying, but when someone spends their time here posting long rants about the Illuminati and then claims to have no time to answer questions and then goes away for days at a time only to come back and repeat the same pattern, I'd say that at the least this is poor time management.
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Post by ka9q on May 19, 2010 13:44:54 GMT -4
There is an intriguing idea for a nuclear rocket that doesn't need an external propellant supply at all.
When a atom of U-235 or Pu-239 fissions, a large part of the energy that is released comes out as the kinetic energy of the fission products. Nuclei are positively charged, so they can be electrostatically guided and, in principle, directed out the back of a rocket engine.
The Isp would be extremely high for this rocket, so high that it might not produce usable thrust even at very high power levels. But it would be another way to build a nuclear rocket.
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raven
Jupiter
That ain't Earth, kiddies.
Posts: 509
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Post by raven on May 20, 2010 14:06:35 GMT -4
I could also, technically, propel a rocket froward by tossing homo sapians out the back. Not very efficient mind you, but it would work.
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Post by grashtel on May 20, 2010 14:59:21 GMT -4
There is an intriguing idea for a nuclear rocket that doesn't need an external propellant supply at all. When a atom of U-235 or Pu-239 fissions, a large part of the energy that is released comes out as the kinetic energy of the fission products. Nuclei are positively charged, so they can be electrostatically guided and, in principle, directed out the back of a rocket engine. The Isp would be extremely high for this rocket, so high that it might not produce usable thrust even at very high power levels. But it would be another way to build a nuclear rocket. I believe that a Fission-Fragment rocket is pretty much what you are describing
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Post by ka9q on May 20, 2010 22:36:42 GMT -4
I could also, technically, propel a rocket froward by tossing homo sapians out the back. Not very efficient mind you, but it would work. Oh, it could be very efficient if you toss him out fast enough. The impulse (which is what rockets give you, so presumably you want to maximize it) would be his mass times the velocity at which you throw him. But the energy it would take you would be one half his mass times his velocity squared. It's that velocity vs velocity squared thing that makes rocketry so frustrating at times.
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Post by JayUtah on May 21, 2010 10:04:45 GMT -4
It's that velocity vs velocity squared thing that makes rocketry so frustrating at times. That's only the first thing that makes rocketry so frustrating. Sutton and Biblarz cover the introduction to it in ch. 3.3 "Isentropic Flow Through Nozzles." (It's a real page-turner.) Later comes all the fun heat transfer and thermodynamics stuff. What's the thermal conductivity of a guy?
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Post by Kiwi on May 22, 2010 9:25:40 GMT -4
Raven: I could also, technically, propel a rocket froward by tossing homo sapians out the back...
Ka9q: Oh, it could be very efficient if you toss him out fast enough.
JayUtah: What's the thermal conductivity of a guy?
This stuff brings to mind the hilarious old BAUT thread (or was it the Bad Astronomy Bulletin Board?) where Jay calculated whether or not a guy could, rocket-fashion, pee himself off the surface of an asteroid which had just enough gravity to hold him there.
"Ten, nine, ignition sequence start..."
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Post by laurel on May 22, 2010 13:50:04 GMT -4
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raven
Jupiter
That ain't Earth, kiddies.
Posts: 509
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Post by raven on May 22, 2010 16:11:52 GMT -4
I could also, technically, propel a rocket froward by tossing homo sapians out the back. Not very efficient mind you, but it would work. Oh, it could be very efficient if you toss him out fast enough. The impulse (which is what rockets give you, so presumably you want to maximize it) would be his mass times the velocity at which you throw him. But the energy it would take you would be one half his mass times his velocity squared. It's that velocity vs velocity squared thing that makes rocketry so frustrating at times. Yeah, but my pitching arm just isn't what it used to be. And it wasn't much to begin with. I remember that old thread, laurel. I am ravens_cry on that forum.
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Post by slang on May 23, 2010 19:53:30 GMT -4
Oh lord, that's a funny thread. I'm debating myself whether I should bump it, so new folks on the board can see it.
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Post by tedward on May 25, 2010 3:59:34 GMT -4
Just wondering if Mr Hagbard (when you read this after I was looking in on your forum) can you stop by and tell where we are wrong? Go on, give it a go. Start your list as was mentioned a good few pages back. We can start with the C rock. So, copy and paste, I don't have any issues with you using mine but you can use yours.
1. C Rock. Explanation (but then you already know the answer here). 2.
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Post by dwight on May 25, 2010 14:03:55 GMT -4
If anyone here has an original Apollo 16 Preliminary Science Report could they take a look at page 4-14 and tell me if the rock has a "c" on it? (NASA SP-315 is the document number)
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Post by Apollo Gnomon on May 25, 2010 19:23:35 GMT -4
wrong thread - post moved
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raven
Jupiter
That ain't Earth, kiddies.
Posts: 509
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Post by raven on May 25, 2010 23:51:44 GMT -4
If anyone here has an original Apollo 16 Preliminary Science Report could they take a look at page 4-14 and tell me if the rock has a "c" on it? (NASA SP-315 is the document number) Well, it's very high contrast and low quality as far as images, but it dpes not appear to be visible in the picture in the Apollo 16 Preliminary Science Report on page 51 of the pdf (Warning: HUGE file)
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