================================================================ -From: David Levine To: "KellySt@aol.com" , "hous0042@maroon.tc.umn.edu" , "T.L.G.vanderLinden@student.utwente.nl" , "stevev@efn.org" , "jim@bogie2.bio.purdue.edu" , "zkulpa@zmit1.ippt.gov.pl" To: "rddesign@wolfenet.com" , "lparker@destin.gulfnet.com" , "DotarSojat@aol.com" , "sl0c8@cc.usu.edu" , "MLEN3097@Mercury.GC.PeachNet.EDU" , "101765.2200@compuserve.com" <101765.2200@compuserve.com> To: "'kgstar@most.fw.hac.com'" Subject: RE: Ox Date: Mon, 17 Jun 1996 10:08:29 -0400 Mime-Version: 1.0 Sounds like it came from that Marshall Savage book. -David >---------- > ================================================================= From: kgstar@most.fw.hac.com[SMTP:kgstar@most.fw.hac.com] Sent: Monday, June 17, 1996 8:44 AM >To: David Levine; KellySt@aol.com; hous0042@maroon.tc.umn.edu; T.L.G.vanderLinden@student.utwente.nl; stevev@efn.org; jim@bogie2.bio.purdue.edu; zkulpa@zmit1.ippt.gov.pl; rddesign@wolfenet.com; lparker@destin.gulfnet.com; DotarSojat@aol.com; sl0c8@cc.usu.edu; MLEN3097@Mercury.GC.PeachNet.EDU; 101765.2200@compuserve.com Subject: Ox >Ran into the following post and woundered how accurate it is. Anyone know? >Kelly >------------------------------------------------------------------ ------- >>I wonder how much space it takes to keep one in oxegen.< >My figure is @ six liters of algea per person. That could be contained in a less than 2 meters of clear tubing, wrapp it helicaly around your light and go for it. >------------------------------------------------------------------ ---- >Kelly Starks Internet: kgstar@most.fw.hac.com >Sr. Systems Engineer >Magnavox Electronic Systems Company >(Magnavox URL: http://www.fw.hac.com/external.html) >------------------------------------------------------------------ ---- ================================================================ X-Sender: kgstar@pophost.fw.hac.com Mime-Version: 1.0 Date: Mon, 17 Jun 1996 09:36:47 -0500 To: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) From: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Subject: Re: Cc: KellySt@aol.com, kgstar@most.fw.hac.com, rddesign@wolfenet.com (Rick Headman) At 2:00 AM 6/16/96, Timothy van der Linden wrote: >Hi Kelly, >I've made time to read your HTML, >About the "Space Settlement Designer's Corner", I know the numbers there aren't yours, but 15-20 kg of water as input seems very much. Also peeing over 7 liters of urine per day seems rather much. Could you explain what I'm overlooking, or am I just some one who use little water? ??!!! Ah, Its an old NASA trick to keep the crew so busy they don't worry about claustrophobia.... You know how many times I've run those numbers without thinking of that? This is embarasing! I also wounder about the .88 kg of solid waste. It certainly seems low compared to the urine numbers. I'll write the author of the web page for info. Its especially questionable given the Space Settlements books list humans needing to drink 2 kg a day when under heavy workloads. And eating about .75 kg of dry food per day. Assuming they arn't talking about a very wet atmosphere, their is some excess mass there somewhere! Also note the Space settlement study numbers list about .4 kg of water intake and 0.857 kg of urine outflow per person per day. I'm betting someone sliped a decimal place somewhere. RICK! Do you remember any submarine numbers on on food and fluids for the crew? >In the "Externally Fueled Fusion Rocket" in the "Laser fuel launchers" paragraph you write: "If you space the tugs out every 60,000 miles for 100,000,000 kilometers..." >The double metric standard is a bit confusing. A few lines further you write "... is 100,000 m/s^2, or about 100,000 G's." I assume you mean 10,000 G's (one zero less). You also say that such accelerations are acceptable, how sure are you about that? Opps, that para should read: Given this system the 'launcher' can be as long as the number of tugs, or as you need at the moment. If you space the tugs out every 60,000 miles (about 100,000 kilometers) for 100,000,000 kilometers (about a 1,000 tugs spaced from here to Mars.) The average G load on a canister exiting at a speed of 1/3rd the speed of light (100,000 kilometers per second), is 50,000 m/s^2, or about 5,000 G's. The canisters would need to take that thrust for the 2000 seconds it would take them to clear the acceleration track. Which seems acceptable for a solid block of reinforced metal and whatever. 5,000 G's is not out of line with the slaming cannon shells and I'C' chips are rated for, so it seems likely. Though that is a lot of load on the reaction mass. I guess I'll have to assume very tough reaction mass. >Finally you end with "The major problems with this system are the amount of reaction mass, and power, necessary to reach the desired maximum speeds may be prohibitive." >You got me confused, what reaction mass are you talking about, all this was about lasers. The lasers fire on a solid block of reaction mass at the back of the fuel canister. (Well actually with Lithium-6 as the fuel theirs just a solid block of fuel with reaction mass behind it.) The micro explosions on the reaction mass cause the forward rocket thrust on the fuel. >I still don't see why one want to use a plasma shield instead of a solid one, could you repeat your latest arguements? To shield the ship from impacts? Mainly because at the spoeeds we're talking about a plasma will seem like a wall to the impacting partical, but it wount transmit a blast shockwaver as well as a solid shield. Also its easier to keep it well ahead of the ship. That would allow the impacting mass a lot more distence to be destroyed before it hit the ship. Finally the plasma, or charged dust, would not be damaged as much by the impacts as a solid mass. >A general note, a lot of your tables (not all) are cropped up (at least with the font I am using), for a reason not clear to me, you have added the WIDTH-tag in the tables, if you would just leave it out, the tables are automatically scaled. I've been having a lot of trouble getter my tables to look right. I've tried entering the html by hand and using what comes out of my wordperfect text editor, but it still doesn't look right. I'm working on it. >I suggest a table of contents at the top of several pages, especially the overview pages like "Mission flight type", "Future tech" and "Mission purpose", it gives an immediate overview of the page. Thats a good point. I'm also woundering if the material should be aranged differntly. More in a central reference area or something. But I guess its good enough where it is. >I see you use "&;" instead of "& " in your "Support Ships: SSTO lander / Hypersonic Cruise Aircraft" page, try "& " the next time :) Opps, typo. Will correct. >The "aero-lan.gif" image at this same page could be emphasized with the 'blue-border-link' so that people know they can get a better look by clicking on it. I wounder if its worth including a larger higher res version for people? >What I wonder about with these support ships, shouldn't they have a little bit more overcapacity, for example they should be able to do multiple landings and takeoffs at a more than 1g planet (at least 2 g). 2g planets are generally gas giants as far as I remember. They'ld be very tough to get off of, and the surface isn't a solid so you couldn't land on them. The ships could land on heavyer worlds, it would just alter the load factor and require very gental landings, and desent heating would be very hard on the hulls. >About the contents of all pages, it all seems OK, I wouldn't have expected otherwise, we have discussed everything several times. >Timothy Ok, Zenon seemed a bit more upset about some things, but said he didn't have time to comment in detail. If nothing else it does put a lot more out there (on the main site) for discussion and debate. Thanks for the review and comment! Kelly ------------------------------------------------------------------ ---- Kelly Starks Internet: kgstar@most.fw.hac.com Sr. Systems Engineer Magnavox Electronic Systems Company (Magnavox URL: http://www.fw.hac.com/external.html) ------------------------------------------------------------------ ---- ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Tue, 18 Jun 1996 00:52:56 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: your HTML-pages You wrote: >Ah, Its an old NASA trick to keep the crew so busy they don't worry about claustrophobia.... Busy running to the toilet/bathroom I assume ;) Let me know what the author (Al Globus or actually Harry L. Shipman) says. >Its especially questionable given the Space Settlements books list humans needing to drink 2 kg a day when under heavy workloads. And eating about .75 kg of dry food per day. Assuming they arn't talking about a very wet atmosphere, their is some excess mass there somewhere! These latter numbers make much more sense. >Also note the Space settlement study numbers list about .4 kg of water intake and 0.857 kg of urine outflow per person per day. I'm betting someone sliped a decimal place somewhere. Yes, the 15-20 could have been 1.5-2.0 but then all the "output"-numbers don't make sense. What also doesn't make sense is the 15-20 since it allowes a deviation of about 25% (Uh sorry guys, today no water) >>In the "Externally Fueled Fusion Rocket" in the "Laser fuel launchers" paragraph you write: "If you space the tugs out every 60,000 miles for 100,000,000 kilometers..." >Opps, that para should read: >Given this system the 'launcher' can be as long as the number of tugs, or as you need at the moment. If you space the tugs out every 60,000 miles (about 100,000 kilometers) for 100,000,000 kilometers (about a 1,000 tugs spaced from here to Mars.) The average G load on a canister exiting at a speed of 1/3rd the speed of light (100,000 kilometers per second), is 50,000 m/s^2, or about 5,000 G's. The canisters would need to take that thrust for the 2000 seconds it would take them to clear the acceleration track. Which seems acceptable for a solid block of reinforced metal and whatever. OK, this looks fine, I'll accept the 5000 G as being possible. >The lasers fire on a solid block of reaction mass at the back of the fuel canister. (Well actually with Lithium-6 as the fuel theirs just a solid block of fuel with reaction mass behind it.) The micro explosions on the reaction mass cause the forward rocket thrust on the fuel. Hmm, I thought you used the momentum of the photons to accelerate the canister, but you may be right this could work even better. Maybe you should add those few lines in your HTML-doc. it would clear up things a little bit more, keep in mind that I already knew what ideas you had. Others (not people of the group) may find it less clear. >>I still don't see why one want to use a plasma shield instead of a solid one, could you repeat your latest arguements? >To shield the ship from impacts? Mainly because at the spoeeds we're talking about a plasma will seem like a wall to the impacting partical, but it wount transmit a blast shockwaver as well as a solid shield. Also its easier to keep it well ahead of the ship. That would allow the impacting mass a lot more distence to be destroyed before it hit the ship. Finally the plasma, or charged dust, would not be damaged as much by the impacts as a solid mass. Maybe you want to include this part in your page. Rex has sent me a paper of his some time ago, it includes a smal part about shielding. From his formulas I can derive that a solid shield of about 30 cm of Aluminium would stop colliding protons at full speed (0.3c). >I've been having a lot of trouble getter my tables to look right. I've tried entering the html by hand and using what comes out of my wordperfect text editor, but it still doesn't look right. I'm working on it. I think entering by hand is the best way to do it, unless you have a good HTML-editor. >>I suggest a table of contents at the top of several pages, especially the overview pages like "Mission flight type", "Future tech" and "Mission purpose", it gives an immediate overview of the page. >Thats a good point. I'm also woundering if the material should be aranged differntly. More in a central reference area or something. But I guess its good enough where it is. Yes, at the moment there isn't much stuff that can refer to it, hopefully in the future that will change. >>The "aero-lan.gif" image at this same page could be emphasized with the 'blue-border-link' so that people know they can get a better look by clicking on it. >I wounder if its worth including a larger higher res version for people? I think you misunderstood, the image you are showing is high-res, but with the HEIGHT and WIDTH tags you have made it look smaller, if you load the image as a separate page (in Netscape pressing the right-mouse button when over a image will pop-up a small menu that allows you to do that). This is the code in your HTML:

While this is the actual size of the image: 888x689 Netscape always scales it to what you have entered, this way you can scale images. >2g planets are generally gas giants as far as I remember. They'ld be very tough to get off of, and the surface isn't a solid so you couldn't land on them. The ships could land on heavyer worlds, it would just alter the load factor and require very gental landings, and desent heating would be very hard on the hulls. You may have a point there, I only wonder if aerobraking is necessary, these ships will have the ability to "freely" maneuver in the starsystem. >Ok, Zenon seemed a bit more upset about some things, but said he didn't have time to comment in detail. If nothing else it does put a lot more out there (on the main site) for discussion and debate. I'll finish that beaming-summary and make it HTML as soon as possible, and put it up at the site too. I've some future plans, but am gathering info at the moment. I got a message from Nick, it seems he finally has vacation and not exams anymore, so hopefully he's going to be creative too. Timothy ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Tue, 18 Jun 1996 00:53:06 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: Post singularity society >>One should consider what abilities one would like to have, speaking 20 languages fluently? Being able to compute the most difficult mathematical problems, figuring out the laws of the universe? Or how to love, to life in this world among and with others? >Whats wrong with choosing all of the above? They are not exclusive. Indeed, but that was not what I was trying to say. Would you want everything that is possible at once? Never ever struggle to get something? I know it sounds tempting at first, but then after a while you may get really bored. And second, living in this world among and with others doesn't sound like there is a "chip" for that, it's something that should be unique for every person. I'm not saying that nothing should be used, but that I wonder if you really want to use it all. >>Another viewpoint is this: >>Today we are wondering, how should we treat nature, our origin and mother? >Generally welth leads to more interest in keeping your home (and planet) clean. Such luxuries are unaffordable by the poor. Hence the higher pollution in the third world, versus the developed world. >Huuummm >Of course since I just mentioned my concern that we would start to become very freaky to the third world. That may just become an increased source of friction. (Then as now.) If these AI's are really so smart and handy, they should be able to create an nice world for everyone. The term wealth is a bit vague, it should be possible to create a balanced world (in all ways) that gives everyone enough space and wealth to be very comfortable. I understand that this may mean that populations should shrink, I think this is only a temporarily problem. If the population should increase then the only solution would be to live in space (or another starsystem) but I'm sure that would solve itself. TimothyDate: Mon, 17 Jun 1996 20:33:31 -0400 From: KellySt@aol.com To: kgstar@most.fw.hac.com Subject: Fwd: Re: Family SSTO design Mime-Version: 1.0 Content-ID: <0_25492_835058010@emout10.mail.aol.com.103532> Content-type: text/plain --------------------- ================================================================ X-Sender: rddesign@wolfenet.com Mime-Version: 1.0 To: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) From: rddesign@wolfenet.com (Ric & Denisse Hedman) Subject: Re: RICK! Do you remember any submarine numbers on on food and fluids for the crew? Kelly; I don't recall any numbers for food or water other than we MADE 8000 gals of water a day and this was used for everything from showering 113 men to cooking and reactor makeup water and secondary coolent Ric ================================================================ X-Sender: kgstar@pophost.fw.hac.com Mime-Version: 1.0 Date: Tue, 18 Jun 1996 08:16:10 -0500 To: rddesign@wolfenet.com (Ric & Denisse Hedman) From: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Subject: Re: Cc: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Hum, oh well. Thanks anyway. If you run across any food and water numbers from underwater friends pass it on. Kelly At 10:19 PM 6/17/96, Ric & Denisse Hedman wrote: >RICK! Do you remember any submarine numbers on on food and fluids for the crew? >Kelly; >I don't recall any numbers for food or water other than we MADE 8000 gals of water a day and this was used for everything from showering 113 men to cooking and reactor makeup water and secondary coolent >Ric ------------------------------------------------------------------ ---- Kelly Starks Internet: kgstar@most.fw.hac.com Sr. Systems Engineer Magnavox Electronic Systems Company (Magnavox URL: http://www.fw.hac.com/external.html) ------------------------------------------------------------------ ---- ================================================================= Date: Tue, 18 Jun 1996 19:34:05 -0700 From: Steve VanDevender To: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Cc: KellySt@aol.com, hous0042@maroon.tc.umn.edu, T.L.G.vanderLinden@student.utwente.nl, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, rddesign@wolfenet.com, David@interworld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, sl0c8@cc.usu.edu, MLEN3097@Mercury.GC.PeachNet.EDU, 101765.2200@compuserve.com Subject: Fwd: Re: Family SSTO design Please don't add 200K attachments to mail messages, especially 200K BinHexed attachments that typically only Mac users can decode. Have some consideration for the people on this list. I wouldn't complain except I generally download my mail to my home computer, and messages like these take quite a bit of time. Having them show up in a format that I can't do anything with makes it a lot more annoying.Date: Wed, 19 Jun 1996 12:40:27 +0200 ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: Plasma mirror Kelly wrote: >Seems the navy lab is now testing a plasma mirror for use in ship board radar systems. (Aviation Week June 10/ p 50) The radar would focus on the stearable plasma sheet. The test sheet was 1 cm thick and 60 x 60 cm square. They are working on upgrading it to a 1.2 - 2 meter square. It bounces microwaves in the 5-20 GHz range and they think similar system could work up to 50 GHz. The current unit needs 2 amps and 20 kilovolts to keep it runing. I assume this is a stationary plasma field, that is kept at the ship. How fast would such a sheet render useless after the power has been cut off? When we would use it as retro mirror, it NEEDS to be loose from the starship. We need to scale this thing up to many hundreds of square meters and several meters thick (the radiation pressure is much higher). >Interesting hey? Yes, are you clearvoyant? Timothy =============================================================== Date: Wed, 19 Jun 1996 08:32:28 -0700 From: Kevin 'Tex' Houston Mime-Version: 1.0 To: Kelly Starks x7066 MS 10-39 Cc: Steve VanDevender , KellySt@aol.com, T.L.G.vanderLinden@student.utwente.nl, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, sl0c8@cc.usu.edu, MLEN3097@Mercury.GC.PeachNet.EDU, 101765.2200@COMPUSERVE.COM Subject: Re: Fwd: Re: Family SSTO design Kelly Starks x7066 MS 10-39 wrote: >At 7:34 PM 6/18/96, Steve VanDevender wrote: >>Please don't add 200K attachments to mail messages, especially 200K BinHexed attachments that typically only Mac users can decode. Have some consideration for the people on this list. >Thats strange. I thought the binhex compresion was a standard internet format. They uploaded from my home system quick enough. >Kelly Well, I was gonna say something about this too, but steve beat me to it. I too am having difficulty decoding your attachment. can you maybe put it on the web site? images are easy to download from there. Kevin ============================================================== From: David Levine To: Steve VanDevender , "'kgstar@most.fw.hac.com'" Cc: "KellySt@aol.com" , "hous0042@maroon.tc.umn.edu" , "T.L.G.vanderLinden@student.utwente.nl" , "stevev@efn.org" , "jim@bogie2.bio.purdue.edu" , "zkulpa@zmit1.ippt.gov.pl" Cc: "rddesign@wolfenet.com" , "lparker@destin.gulfnet.com" , "DotarSojat@aol.com" , "sl0c8@cc.usu.edu" , "MLEN3097@Mercury.GC.PeachNet.EDU" , "101765.2200@compuserve.com" <101765.2200@compuserve.com> Subject: RE: Fwd: Re: Family SSTO design Date: Wed, 19 Jun 1996 12:16:12 -0400 Mime-Version: 1.0 It is, of course, -possible- to unBinHex something on a PC, but it -does- take quite a bit of work. -David >---------- >From: kgstar@most.fw.hac.com[SMTP:kgstar@most.fw.hac.com] Thats strange. I thought the binhex compresion was a standard internet format. They uploaded from my home system quick enough. ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Wed, 19 Jun 1996 23:00:44 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: Post singularity society Kelly wrote: >Don't see the connection. We have the technology and resources to make a nice wealthy world for everyone now. Doesn't mean everyone can or will join in. (No we don't need to shrink the population.) Many simple things still need to be done by humans, growing food, building houses etc. Transferring these goods also costs lots of money and human work. All this makes that many normal Western needs are not free at all, when energy is free and machines (AIs) do the work then the resources are available, today these resources are only available to those who have enough money. I thus don't see why you can say that technology and resources are not the problem. Timothy ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Wed, 19 Jun 1996 23:00:53 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: Fwd: Re: Family SSTO design Kelly wrote: >I ran into a guy whos father may have been the first person to seriously propose a SSTO launcher. I had him send me some images he has (attached). How about we add him to the LIT site? It would get us some attention! Dave? Do we really need to worry about in system transfer? >From all things we talked about, I think that would be the easiest part. I assume that at the time humankind will build a starship, in solarsystem travel will be as normal as flying over the ocean (with an airplane). Timothy P.S. The images you sent seriously need to be gamma-corrected, they are almost black at my screen. ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Wed, 19 Jun 1996 23:00:47 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: your HTML-pages >>>>I still don't see why one want to use a plasma shield instead of a solid one, could you repeat your latest arguements? >>>To shield the ship from impacts? Mainly because at the spoeeds we're talking about a plasma will seem like a wall to the impacting partical, but it wount transmit a blast shockwaver as well as a solid shield. Also its easier to keep it well ahead of the ship. That would allow the impacting mass a lot more distence to be destroyed before it hit the ship. Finally the plasma, or charged dust, would not be damaged as much by the impacts as a solid mass. >>Maybe you want to include this part in your page. Rex has sent me a paper of his some time ago, it includes a smal part about shielding. From his formulas I can derive that a solid shield of about 30 cm of Aluminium would stop colliding protons at full speed (0.3c). >What about colliding pebbles? Can't we shoot them with a laser or something like that? I can return the question, do you think that several miles of plasma will ionize and stop the pebble? Before you answer that, what is the density of the plasma? Assuming it would have the same density as air (standard pressure) that would make its density about 2000 times less than aluminium. In other words for every mile of plasma you could just as well use 50 cm of aluminium plating, without the need to contain an renew the plasma. (Yes, some of the holes in the aluminium may have to be repaired also.) I'm wondering if the density of air during a few miles will be enough, meteors colliding with Earth's atmosphere may burn away, but their speed is usually much less than 1E8 m/s. Don't underestimate the velocity difference, I believe meteor speeds are in the 1E4 m/s range, since kinetic energy squares velocity (E=0.5mv^2) the difference in velocity (4 orders of magnetude) will double to about 8 orders of magnetude. (would that mean 1E8 times more plasma needed?) Let me know what you think... Timothy P.S. (Density of air=1.293 kg/m3 Density of aluminium=2700 kg/m^3) ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Thu, 20 Jun 1996 00:47:27 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: un-BinHex-ing Kevin wrote: >Well, I was gonna say something about this too, but steve beat me to it. I too am having difficulty decoding your attachment. can you maybe put it on >the web site? images are easy to download from there. To those unlucky ones and using windows (is that a pleonasm?) there is a program called WinCode it is able to en/decode several formats (BinHex,Base64,UUencode and a few others). Try getting version 2.6.6 its about 600 kb zipped. Also the mail-program Windows Eudora decodes BinHex automatically (the light version of Eudora is free). Tim ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Thu, 20 Jun 1996 00:47:32 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: Plasma mirror Kelly replied: >>I assume this is a stationary plasma field, that is kept at the ship. -- >On the ship yes, stationary no. It is used as the moving reflector that sweeps the beem back and forth. The artical mentioned it can re-aim in 10 milisec. (I think.) I meant the latter, so far I think I understand. >>- How fast would such a sheet render useless after the power has been cut off? >Almost as fast as it can be reaimed I'ld guess. One other question that I'm thinking of, how fast can it be recreated from "scratch". I could imagine that it is blown away faster than it can be build. (We cannot just turn off the maser beam, waiting for the ion-mirror to be created.) >I was thinking the ions would be blown out of the plasma sheet as they interact with the beam. Since the beam presure would be far greater than the holding magnetic fields I guess a "soft" attachment to the starship could work >>Yes, are you clearvoyant? >What can I say. Great minds think alike. Am I sorry I asked.... ;)) Timothy ================================================================== Date: Wed, 19 Jun 1996 23:48:21 -0400 From: KellySt@aol.com To: kgstar@most.fw.hac.com Subject: Fwd: Announcing messagenet --------------------- Date: Wed, 19 Jun 1996 22:21:33 -0700 From: Steve VanDevender To: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Cc: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU Subject: un-BinHex-ing Timothy van der Linden writes: >Kevin wrote: >>Well, I was gonna say something about this too, but steve beat me to it. I too am having difficulty decoding your attachment. can you maybe put it >on >the web site? images are easy to download from there. >To those unlucky ones and using windows (is that a pleonasm?) there is a program called WinCode it is able to en/decode several formats (BinHex,Base64,UUencode and a few others). Try getting version 2.6.6 its about 600 kb zipped. >Also the mail-program Windows Eudora decodes BinHex automatically (the light version of Eudora is free). >Tim I use Linux and read all my mail using the VM package that runs in GNU Emacs. I can unpack MIME messages and uudecode stuff. I don't have a binhex utility, and I can't use a binhex utility that runs under Windows. If you're going to use MIME attachements, at least use the standard base64 encoding, or uuencode as a second choice. No other formats are either standard or widely available on different machines. ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Thu, 20 Jun 1996 13:27:33 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: shielding >>>What about colliding pebbles? >>Can't we shoot them with a laser or something like that? >For bigger rocks yes, for little stuff probably not. The biggest problem is detecting the pebbles (and smaller) soon enough, you wouldn't care about shooting it economically, just a big laser beam (several metres in diameter) would do. >>I can return the question, do you think that several miles of plasma will ionize and stop the pebble? >>Before you answer that, what is the density of the plasma? Assuming it would have the same density as air (standard pressure) that would make its density about 2000 times less than aluminium. In other words for every mile of plasma you could just as well use 50 cm of aluminium plating, without the need to contain an renew the plasma. (Yes, some of the holes in the aluminium may have to be repaired also.) >You forget the damage the rock will do on the ship. The shock wave will ripple explosivly through a solid structure. It woun't travel through a charged dust cloud. I think the shockwave isn't the main problem, one could make the connection between the ship and the shield like a damper, that would decrease the wear and tear on the ship when colliding with occasional pebbles. >One of the problems of a metor in an atrmosphere is that it may not have enough time to evaporate before it blasts throgh the atmosphere. In the same way a pebble hiting the aluminum armor would vaporise inside the armor without anywhere for the blast to go but in the ship. One could make several layers of alu-plating separated by a few centimeters, so that explosions could get out, another method would be to make the alu-shielding full of empty-bubbles (like a sponge) these bubbles could catch the "first hit". >All in all a lot easier on the ship then a direct impact at full speed. What you didn't address is the fact that a plasma cloud may be much heavier than a solid shield, that would be a serious disadvantage, certainly if the plasma cloud needs to be "refreshed" (in steps) many times. Tim ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Thu, 20 Jun 1996 13:28:00 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: Post singularity society Kelly wrote: >I.E. we are doomed, and all civilization will collapse, or we will survive only by stealing from everyone else. This is nonsence, but its geting to be common enough nonsence to worry me, and your comment about "maybe we need to have fewer people" seemed to suggest it. I wrote the latter because I had in mind that many may want to live a bit more roomier. >As to things that still need to be done by humans (growing food, building houses etc) the number of humans neccisary to do that is droping rapidly (bad news if you work in those fields. Thats A BIG issue in the U.S.). I assume that is an upcoming problem for all developed countries. >But the big issues are often cultural. Everone can by the same equipment. Yes, I've that feeling too, I always wonder if people in Third World countries want to do the work themselves, or that they want us to do the job for them. I often get the idea that the latter attracts the biggest group. >But often even if poor counties (or rich third world ones) do by it and the resorces, or even if they are given them. They can't assimilate and use them. The mid east spent a ton importing equip and geting international contracts. But then they found their people for cultural reasons couldn't/wouldn't operate the systems correctly. All the contracts vanished. All the companies left. It wasn't a mater of training. They knew how, they just wouldn't. Doing what was nessisary for the equipment was unacceptable to them culturally. Indeed, I've heard several times that as soon as they get their money they leave and come back when the money is gone. The only way to make them come back, is to pay them just enough to life one day. They seem to be happy with what they have. Sure they like new "toys", just like we do, but they don't find them important enough to work for day and night. They often have a lot of spare time (or at least we see it as spare time), the drawback is that their lives are a bit more insecure. (With todays crime one can doubt that.) Most people from Western cultures want to or "are forced to" make enough money to live according to high standards. Maybe someday most people of undeveloped countries decide to do like us, one simply cannot force that onto someone. Of course they like what we have, but most of us like things we don't have (yet). >Thats going to be a bigger issue as more technologies and issues get out to the third world. They will be forced to deal with things they don't want to deal with, and may just drop it and not adapt. But when they stay where they are, and the rest of the world races past. They will not blame themselves. I'm not sure who they want to blame, it's always easier to blame someone else, I think they should show some initiatives themselves first. Maybe we are partly to blame, we buy lots of resources from them, things they probably will never get back (at least not in usable form). On the other hand their leaders should be smart enough to regulate that, but it seems they (and their friends) are the only ones who get the money. So most of these countries have internal problems, and the poor people know that it helped more to ask Western countries for aid than to ask their own governments. I believe that we generally agree... Timothy ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Thu, 20 Jun 1996 13:27:54 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: In-system vessels >>From all things we talked about, I think that would be the easiest part. I assume that at the time humankind will build a starship, in solarsystem travel will be as normal as flying over the ocean (with an airplane). >Well by 2050 it wount be that common. Also LIT does have a space development (or whatever its named) section. Not just a starship design section. This is an invalid argument, assuming we are going to build a starship around the year 2050, I'm sure we know rather well how to do in-system travel, then we also don't worry about a factor 10 more or less of fuel- costs. (Of course we do worry, but compared to 1E18 watt everything is small.) I can't see us building a 1E8 kg starship without being able to fly without much problems in our own system. It would be like sailing over the ocean with a four-masts-ship while barely knowing how to row across the river. Timothy ================================================================ X-Sender: kgstar@pophost.fw.hac.com Mime-Version: 1.0 Date: Thu, 20 Jun 1996 07:32:34 -0500 To: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) From: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Subject: Re: Plasma mirror Cc: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU At 12:47 AM 6/20/96, Timothy van der Linden wrote: >Kelly replied: >>>- How fast would such a sheet render useless after the power has been cut off? >>Almost as fast as it can be reaimed I'ld guess. >One other question that I'm thinking of, how fast can it be recreated from "scratch". I could imagine that it is blown away faster than it can be build. (We cannot just turn off the maser beam, waiting for the ion-mirror to be created.) True. We'ld need to know how much mass was neccissary to reflect the beam, and how fast it would be blown clear. In general we'ld need to know the specific interaction between the beam and the plasma cloud. >>I was thinking the ions would be blown out of the plasma sheet as they interact with the beam. Since the beam presure would be far greater than the holding magnetic fields >I guess a "soft" attachment to the starship could work >>>Yes, are you clearvoyant? >>What can I say. Great minds think alike. >Am I sorry I asked.... ;)) >Timothy I fore saw you would be. ;) Kelly ------------------------------------------------------------------ ---- Kelly Starks Internet: kgstar@most.fw.hac.com Sr. Systems Engineer Magnavox Electronic Systems Company (Magnavox URL: http://www.fw.hac.com/external.html) ------------------------------------------------------------------ ---- ================================================================ X-Sender: kgstar@pophost.fw.hac.com Mime-Version: 1.0 Date: Thu, 20 Jun 1996 07:44:13 -0500 To: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) From: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Subject: Re: shielding Cc: KellySt@aol.com, kgstar@most.fw.hac.com At 1:27 PM 6/20/96, Timothy van der Linden wrote: >>>>What about colliding pebbles? >>>Can't we shoot them with a laser or something like that? >>For bigger rocks yes, for little stuff probably not. >The biggest problem is detecting the pebbles (and smaller) soon enough, you wouldn't care about shooting it economically, just a big laser beam (several metres in diameter) would do. >>>I can return the question, do you think that several miles of plasma will ionize and stop the pebble? >>>Before you answer that, what is the density of the plasma? Assuming it would have the same density as air (standard pressure) that would make its density about 2000 times less than aluminium. In other words for every mile of plasma you could just as well use 50 cm of aluminium plating, without the need to contain an renew the plasma. (Yes, some of the holes in the aluminium may have to be repaired also.) >>You forget the damage the rock will do on the ship. The shock wave will ripple explosivly through a solid structure. It woun't travel through a charged dust cloud. >I think the shockwave isn't the main problem, one could make the connection between the ship and the shield like a damper, that would decrease the wear and tear on the ship when colliding with occasional pebbles. >>One of the problems of a metor in an atrmosphere is that it may not have enough time to evaporate before it blasts throgh the atmosphere. In the same way a pebble hiting the aluminum armor would vaporise inside the armor without anywhere for the blast to go but in the ship. >One could make several layers of alu-plating separated by a few centimeters, so that explosions could get out, another method would be to make the alu-shielding full of empty-bubbles (like a sponge) these bubbles could catch the "first hit". The layers shield design is standard for orbital debries shield, but the blast would tear open parts of the foam. >>All in all a lot easier on the ship then a direct impact at full speed. >What you didn't address is the fact that a plasma cloud may be much heavier than a solid shield, that would be a serious disadvantage, certainly if the plasma cloud needs to be "refreshed" (in steps) many times. >Tim I can't see any reason it would be as heavy as a solid shield. Its volume of interaction is larger. and it doesn't need to be stressed to take the heavy blast effects of direct impacts. Given that everything that hits it will itself become more of the cloud, it should be fairly self sustaining. Kelly ------------------------------------------------------------------ ---- Kelly Starks Internet: kgstar@most.fw.hac.com Sr. Systems Engineer Magnavox Electronic Systems Company (Magnavox URL: http://www.fw.hac.com/external.html) ------------------------------------------------------------------ ---- ================================================================ X-Sender: kgstar@pophost.fw.hac.com Mime-Version: 1.0 Date: Thu, 20 Jun 1996 08:00:30 -0500 To: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) From: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Subject: Re: Post singularity society Cc: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU At 1:28 PM 6/20/96, Timothy van der Linden wrote: >Kelly wrote: >>I.E. we are doomed, and all civilization will collapse, or we will survive only by stealing from everyone else. This is nonsence, but its geting to be common enough nonsence to worry me, and your comment about "maybe we need to have fewer people" seemed to suggest it. >I wrote the latter because I had in mind that many may want to live a bit more roomier. If that was true we wouldn't be rushing into the cities. ;) >>As to things that still need to be done by humans (growing food, building houses etc) the number of humans neccisary to do that is droping rapidly (bad news if you work in those fields. Thats A BIG issue in the U.S.). >I assume that is an upcoming problem for all developed countries. And developing. The green revolution actually increase hunger since it was so much more productive it put a lot of subsistence farmers out of work. >>But the big issues are often cultural. Everone can by the same equipment. >Yes, I've that feeling too, I always wonder if people in Third World countries want to do the work themselves, or that they want us to do the job for them. I often get the idea that the latter attracts the biggest group. It varies, but yes a lot of coutries don't understand why groups that do the work should get more of the reward than groups that do nothing. That was a big issue that trashed the law of the sea treaty negotiations years ago, and stoped sea bottom mining projects in their tracks. Its been a constant fear that the same thing could stop space explotation in its tracks in the near future. >>But often even if poor counties (or rich third world ones) do by it and the resorces, or even if they are given them. They can't assimilate and use them. The mid east spent a ton importing equip and geting international contracts. But then they found their people for cultural reasons couldn't/wouldn't operate the systems correctly. All the contracts vanished. All the companies left. It wasn't a mater of training. They knew how, they just wouldn't. Doing what was nessisary for the equipment was unacceptable to them culturally. >Indeed, I've heard several times that as soon as they get their money they leave and come back when the money is gone. The only way to make them come back, is to pay them just enough to life one day. They seem to be happy with what they have. Sure they like new "toys", just like we do, but they don't find them important enough to work for day and night. >They often have a lot of spare time (or at least we see it as spare time), the drawback is that their lives are a bit more insecure. (With todays crime one can doubt that.) >Most people from Western cultures want to or "are forced to" make enough money to live according to high standards. Maybe someday most people of undeveloped countries decide to do like us, one simply cannot force that onto someone. Of course they like what we have, but most of us like things we don't have (yet). Yeah they screem when they see how well, and long, we live compared to them. But screem just as loud when they have to do the dirty work to get here. >>Thats going to be a bigger issue as more technologies and issues get out to the third world. They will be forced to deal with things they don't want to deal with, and may just drop it and not adapt. But when they stay where they are, and the rest of the world races past. They will not blame themselves. >I'm not sure who they want to blame, it's always easier to blame someone else, I think they should show some initiatives themselves first. They blame us. We have it and woung give it to them for free. >Maybe we are partly to blame, we buy lots of resources from them, things they probably will never get back (at least not in usable form). On the other hand their leaders should be smart enough to regulate that, but it seems they (and their friends) are the only ones who get the money. You kind of have it backwards. Their economies are almost completly involved around selling us raw materials. They don't need the ores or fuel. They don't have an industry that can use it. Also in the future it woun't be valuble. (what is and isn't a valuble resource changes radically over time and technology.) Thier biggest fear is that we (developed world) will develop alternate sources. Thats one of the things that trashed the law of the sea treaty and will be a risk to space development treaties. If we develop mining in the solar system. We will have access to ore and fuel far more numerous and of far better quality then the third world can sell to us, and without political or ecological impacts to locals. So we, and probably will rapidly, supply all our needs (or theirs for that mater) cheaper from space. I.E. we will stop buying from them! Their economies will be colapse! >So most of these countries have internal problems, and the poor people know that it helped more to ask Western countries for aid than to ask their own governments. And the governments have found that they can ask for aid, get it, and sell the materials for cash, or use it as a weapon domestically. >I believe that we generally agree... >Timothy True. Kelly ------------------------------------------------------------------ ---- Kelly Starks Internet: kgstar@most.fw.hac.com Sr. Systems Engineer Magnavox Electronic Systems Company (Magnavox URL: http://www.fw.hac.com/external.html) ------------------------------------------------------------------ ---- ================================================================ X-Sender: kgstar@pophost.fw.hac.com Mime-Version: 1.0 Date: Thu, 20 Jun 1996 08:02:31 -0500 To: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) From: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) Subject: Re: In- system vessels Cc: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU At 1:27 PM 6/20/96, Timothy van der Linden wrote: >>>From all things we talked about, I think that would be the easiest part. I assume that at the time humankind will build a starship, in solarsystem travel will be as normal as flying over the ocean (with an airplane). >>Well by 2050 it wount be that common. Also LIT does have a space development (or whatever its named) section. Not just a starship design section. >This is an invalid argument, assuming we are going to build a starship around the year 2050, I'm sure we know rather well how to do in-system travel, then we also don't worry about a factor 10 more or less of fuel- costs. (Of course we do worry, but compared to 1E18 watt everything is small.) >I can't see us building a 1E8 kg starship without being able to fly without much problems in our own system. >It would be like sailing over the ocean with a four-masts-ship while barely knowing how to row across the river. >Timothy What I was saying is that LIT has a section (not well traveled but there) that covers space development, not starship design. This ship would fit into that rather then the starship design project. Kelly ------------------------------------------------------------------ ---- Kelly Starks Internet: kgstar@most.fw.hac.com Sr. Systems Engineer Magnavox Electronic Systems Company (Magnavox URL: http://www.fw.hac.com/external.html) ------------------------------------------------------------------ ---- ================================================================== From: David Levine To: "T.L.G.vanderLinden@student.utwente.nl" , "'kgstar@most.fw.hac.com'" Cc: "KellySt@aol.com" , "stevev@efn.org" , "jim@bogie2.bio.purdue.edu" , "zkulpa@zmit1.ippt.gov.pl" , "hous0042@maroon.tc.umn.edu" , "rddesign@wolfenet.com" Cc: "lparker@destin.gulfnet.com" , "DotarSojat@aol.com" , "neill@foda.math.usu.edu" , "101765.2200@compuserve.com" <101765.2200@compuserve.com>, "MLEN3097@Mercury.GC.PeachNet.EDU" Subject: RE: In-system vessels Date: Thu, 20 Jun 1996 09:45:35 -0400 Mime-Version: 1.0 As perhaps totally separate from the starship project? i.e. another project, in another "universe"? I've always wanted to have a second design project based on in-system travel, mainly because it's more realistic for the near term future... David >---------- >From: kgstar@most.fw.hac.com[SMTP:kgstar@most.fw.hac.com] What I was saying is that LIT has a section (not well traveled but there) that covers space development, not starship design. This ship would fit into that rather then the starship design project. ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Thu, 20 Jun 1996 19:42:47 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: shielding >>One could make several layers of alu-plating separated by a few centimeters, so that explosions could get out, another method would be to make the alu-shielding full of empty-bubbles (like a sponge) these bubbles could catch the "first hit". >The layers shield design is standard for orbital debries shield, but the blast would tear open parts of the foam. Assuming there are not to many "pebbles", these holes can be repaired. >I can't see any reason it would be as heavy as a solid shield. Its volume of interaction is larger. and it doesn't need to be stressed to take the heavy blast effects of direct impacts. Given that everything that hits it will itself become more of the cloud, it should be fairly self sustaining. I just cannot imagine how you are going to contain and push an ion cloud of several miles long and hundreds of meters in diameter, without loosing much of it. Tim ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Thu, 20 Jun 1996 19:42:53 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com, neill@foda.math.usu.edu, 101765.2200@compuserve.com, MLEN3097@Mercury.GC.PeachNet.EDU From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: In-system vessels >What I was saying is that LIT has a section (not well traveled but there) that covers space development, not starship design. This ship would fit into that rather then the starship design project. Well then that is fine with me, I just wanted to make clear the difference. Timothy ============================================================ ================================================================ X-Sender: rddesign@wolfenet.com Mime-Version: 1.0 To: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) From: rddesign@wolfenet.com (Ric & Denisse Hedman) Subject: Re: Human numbers Fresh water/potable water weighs 8.3/lbs/gal >About all that urine... >>Date: Thu, 20 Jun 1996 13:20:30 -0700 >>From: Al Globus To: kgstar@most.fw.hac.com >>Subject: Re: Human numbers >>water weighs about 9 pounds per gallon, or about four kilograms per gallon. 7 Kilograms of urine per day works out to less than two gallons. This seems a little high, but not ridiculous. I suggest you try an experiment for a few days and see. Also, remember that these numbers were generated in the high-resource usage 60's. If you find better numbers, please let me know. >>X-Sender: kgstar@pophost.fw.hac.com >>Mime-Version: 1.0 >>Content-Type: text/plain; charset="us-ascii" Date: Mon, 17 Jun 1996 08:17:02 -0500 >>From: kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) >>Hi Al, >>I'm working up a draft web page for a group thats trying to do some serious analysis of what kind of starships would be possible in the mid 21st century. As part of that we were doing food consumption numbers and I reffered to your web page table >> and started to use it. When some members started to review it, I realized I hadn't looked carfully enough at the numbers. For example over 7 kilo of urine a day seem rather high to me, not to mention 15-20 kilo of drinking and food related water intakes. Could you explain? >>Kelly Starks >>>X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 >>>Date: Sun, 16 Jun 1996 02:00:10 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: >>>Hi Kelly, >>>I've made time to read your HTML, >>>About the "Space Settlement Designer's Corner", I know the numbers there aren't yours, but 15-20 kg of water as input seems very much. Also peeing over 7 liters of urine per day seems rather much. Could you explain >>what I'm >>>overlooking, or am I just some one who use little water? ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Fri, 21 Jun 1996 13:29:03 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: shielding >>Assuming there are not to many "pebbles", these holes can be repaired. >While underway at .3 - .4 c? I'm not going out to fix it! ;) I already thought of that, some shielded robots could do that. >>I just cannot imagine how you are going to contain and push an ion cloud of several miles long and hundreds of meters in diameter, without loosing much of it. >You forget durring the bulk of the trip your just coasting. You just throw the dust ahead of you and let it drift ahead of you. Also I was never thinking of a heavily ionized plasma cloud. Just some dust with enough of a charge to keep it from clumping. About the only time you should have a problem is when you return to earth with a microwave decelerated ship. The beam could blast the cloud back into you. Then again the cloud doesn't have to be reactive to microwaves. I indeed didn't think of that, however acceleration and (worse) deceleration may take some time to, actually these two periods are the most likely to get the pebbles, since they are nearest to the solarsystems. During the "coasting" phase there will still be ISM that "sands" the shield, while this sanding may not influence the ship much, it may have a larger influence on the shielding-cloud, with the effect that it is pushed backwards and outwards. I wasn't directly saying the plasma was heavy ionized, I meant that the density of the particles in the cloud might need to become high (I suggested something like the density of air at standard pressure). Ionized or not, I assume it will become more ionized when it collides with ISM. I believe we estimated something like a few hundred grams of ISM per second, so I think that can not be neglected. Of course you say that will replenish the cloud at the same time, but I'm not so sure, the cloud may become warmer and harder to control. By the way, in the past someone suggested a shield of ice, I wonder if such at shield would not sublimate/evaporate too soon. Do you know about that? (I'm not suggesting to use an ice-shield.) Timothy ================================================================ X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0 Date: Sat, 22 Jun 1996 17:41:12 +0100 To: KellySt@aol.com, kgstar@most.fw.hac.com From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) Subject: Re: shielding >>I indeed didn't think of that, however acceleration and (worse) deceleration may take some time to, actually these two periods are the most likely to get the pebbles, since they are nearest to the solarsystems. >Decel isn't a problem (excluding the microwave problem). You just let the cloud race on ahead of you and clear your path. Theoretically a rock can come from the side and enter the cloud at a point near the starship, then the shield won't do enough anymore. >Then again, we don't really know whats in interstellar space. That makes it all even more scary... >>I wasn't directly saying the plasma was heavy ionized, I meant that the density of the particles in the cloud might need to become high (I suggested something like the density of air at standard pressure). >I was thinking of the cloud more as ground dust or sand. Dust/sand wouldn't that increase density (thus weight) even more? Give me the weight of your shield, then we can make a fair comparison between a solid and a fuzzy shield. >I'm not sure what >the density would be like, but I'm pretty sure whatever is ahead of you will get ground away by a 100,000,000 m/s sand blasting! Well it better be, it needs about 0.1 milli seconds to travel 10 kilometers. Hmmm, I wonder, could we make a long container, with the front side open, inside the container the sand is "stirred" to make a cloud. (shouldn't be to hard in zero-g) This way the stuff stays contained rather well, without much effort. I'm only worrying if such a long structure will hold under 1g acceleration. If one wanted such a thing from all sides, you could even build the starship inside the container, however the shielding may become to heavy. >The numbers I worked up in the report were " --At 0.333c, using the above design figures, our 1000 km in diameter scoop, scoops up a ram flow of 131.4 grams per second." Given a ship with 1/1,000th the diameter we'ld get 1/1,000,000 th the mass pick up. About 11 grams a day. Oh yeah, the diameter is different, sorry. Tim