Re: [Vo]:Mars One - Humans on Mars in 2023
A somewhat costly state-of-the-art manned outpost of considerable size should be established on the Moon. Not only should it be designed for scientific research, but also as a tourist destination. Money to support this endeavor would come from taxes private capital, and/or tourism. Based on the current mode of technology, it's impractical or unwise to invest in any thing more than the current various probes in orbit and/or exploring the terrain their. The Moon would present more than enough of a challenge for establishing presence their, and at the same time provide us with a great deal of data for future endeavors. /HTML
PioneerOne was Re: [Vo]:Mars One - Humans on Mars in 2023
Mars One will be second anyway. ;-) The whole story at: http://vodo.net/pioneerone Download for free the first 6 episodes, worth watching. If you enjoy contribute to cover production costs of next episodes. mic 2012/6/6 Daniel Rocha danieldi...@gmail.com: Realities shows are successful because the success of one relies on the humiliation and exclusion of other participants, like in the old Coliseum. That is not possible in this mission, though, unless you kill passengers, like in the old Coliseum. 2012/6/6 Patrick Ellul ellulpatr...@gmail.com Funded by marketing it as one big reality show... Possible?? And would you buy a one way ticket to Mars? http://mars-one.com/en/ Regards, Patrick -- Patrick www.tRacePerfect.com The daily puzzle everyone can finish but not everyone can perfect! The quickest puzzle ever! -- Daniel Rocha - RJ danieldi...@gmail.com
Re: [Vo]:Mars One - Humans on Mars in 2023
I'm sorry, but as an engineer if you imagine that you can build a fusion powered spacecraft with an exhaust velocity of 7.5e6m/s and 40MW of engine power per kg of spacecraft (from rocket equation with 20% fuel use in 2 days at 1g thrust), when nobody can yet build a viable self sustaining fusion reactor at any size then you don't deserve a response. On 6 June 2012 05:16, mix...@bigpond.com wrote: In reply to Patrick Ellul's message of Wed, 6 Jun 2012 14:10:21 +1000: Hi, [snip] I wrote to Elon Musk offering to help him build a fusion powered shuttle to get us there in 2 days at 1 g with only 20% fuel mass. No response. Funded by marketing it as one big reality show... Possible?? And would you buy a one way ticket to Mars? http://mars-one.com/en/ Regards, Patrick Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
I say, why waste time going to Mars, when you can shoot for the stars! We need to set our goals and/or expectations higher or farther actually. While it would be a very cool thing to have some fellow Humans residing on Mars, it's getting there in a vastly improved capacity that will enable any destination in space more practical. BTW, I have a question about Venus's polar regions... Wouldn't they be a more likely choice to plan a scientific outpost or habitat, rather than Mars? Due to the distance, Mars tends to be too cold and it's terrain is too dry, so why even entertain the idea of trying to survive there? We should build space stations either in orbit and/or geosynchronous orbit around all the innerplanets and/or their satellites, and then make travel to those destinations on a regular basis. Trying to live in extreme conditions on an inhospitable planet doesn't make too much sense except for resources, and should be done on a limited basis. To me, it's more feasible to have space stations in thruout innerplanetary locations as a first step to permanently occupying space. /HTML
Re: [Vo]:Mars One - Humans on Mars in 2023
In reply to Robert Lynn's message of Wed, 6 Jun 2012 12:55:31 +0100: Hi, [snip] You don't understand the nature of technological breakthroughs do you. I'm sorry, but as an engineer if you imagine that you can build a fusion powered spacecraft with an exhaust velocity of 7.5e6m/s and 40MW of engine power per kg of spacecraft (from rocket equation with 20% fuel use in 2 days at 1g thrust), when nobody can yet build a viable self sustaining fusion reactor at any size then you don't deserve a response. On 6 June 2012 05:16, mix...@bigpond.com wrote: In reply to Patrick Ellul's message of Wed, 6 Jun 2012 14:10:21 +1000: Hi, [snip] I wrote to Elon Musk offering to help him build a fusion powered shuttle to get us there in 2 days at 1 g with only 20% fuel mass. No response. Funded by marketing it as one big reality show... Possible?? And would you buy a one way ticket to Mars? http://mars-one.com/en/ Regards, Patrick Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
Sadly I do understand, I am just not blind to the implied engineering requirements. *40MW/kg !* The highest power to weight machines (outside of bombs) that humans have ever build were the space shuttle main engines, they did about 3MW/kg utilising a supply of LH2, the best possible coolant, to keep the engine from melting. That is a luxury you do not have with fusion in an ultra-high Isp engine. At 40MW/kg (and would need to be much higher than that if you wanted any payload) even if your engine miraculously manages to eject 99% of that energy in the exhaust you still have somehow come up with a way of radiating 400kW for every kg of spacecraft from your engine cooling system. And any hot fusion engine requires a driver to initiate the fusion, typically recirculating 0.1-10% of the fusion power output. So being insanely optimistic with a Q of 1000 you are recirculating 40kW/kg of space craft power (4GW for a 100 tonne craft), and somehow cooling that power collection and driver systems as well, all for some small fraction of your total mass budget. Then there are the shielding requirements for the vehicle and occupants who are sitting next to this multiple TW output engine and its incredible gamma ray (at minimum) output. Which are just a couple of simple examples as to why anyone with even cursory knowledge of actual engineering knows that what you suggest is so far beyond the feasible that it is quite simply ridiculous. 100 years from now it might be possible for a spacecraft to achieve 1% of the power and acceleration levels you suggest at an Isp of 7.5e6m/s, but I wouldn't bet on it. On 6 June 2012 21:31, mix...@bigpond.com wrote: In reply to Robert Lynn's message of Wed, 6 Jun 2012 12:55:31 +0100: Hi, [snip] You don't understand the nature of technological breakthroughs do you. I'm sorry, but as an engineer if you imagine that you can build a fusion powered spacecraft with an exhaust velocity of 7.5e6m/s and 40MW of engine power per kg of spacecraft (from rocket equation with 20% fuel use in 2 days at 1g thrust), when nobody can yet build a viable self sustaining fusion reactor at any size then you don't deserve a response. On 6 June 2012 05:16, mix...@bigpond.com wrote: In reply to Patrick Ellul's message of Wed, 6 Jun 2012 14:10:21 +1000: Hi, [snip] I wrote to Elon Musk offering to help him build a fusion powered shuttle to get us there in 2 days at 1 g with only 20% fuel mass. No response. Funded by marketing it as one big reality show... Possible?? And would you buy a one way ticket to Mars? http://mars-one.com/en/ Regards, Patrick Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
In reply to Robert Lynn's message of Wed, 6 Jun 2012 22:49:45 +0100: Hi, [snip] That is a luxury you do not have with fusion in an ultra-high Isp engine. It is also a luxury you don't need. The trick is to perform the reaction in space itself. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
Like Friedwart Winterberg's Supermarx concept? http://nextbigfuture.com/2008/12/micro-fusion-for-space-propulsion-and.html I really like the concept, but there is still no way that it can achieve the power to weight required to give 1g at 7.5e6m/s Isp. Heat loads and driver power requirements are simply too high. On 6 June 2012 23:22, mix...@bigpond.com wrote: In reply to Robert Lynn's message of Wed, 6 Jun 2012 22:49:45 +0100: Hi, [snip] That is a luxury you do not have with fusion in an ultra-high Isp engine. It is also a luxury you don't need. The trick is to perform the reaction in space itself. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
In reply to Robert Lynn's message of Wed, 6 Jun 2012 22:49:45 +0100: Hi, [snip] Sadly I do understand, I am just not blind to the implied engineering requirements. *40MW/kg !* The highest power to weight machines (outside of bombs) that humans have ever build were the space shuttle main engines, they did about 3MW/kg utilising a supply of LH2, the best possible coolant, to keep the engine from melting. That is a luxury you do not have with fusion in an ultra-high Isp engine. Actually, a bomb is not a bad analogy. The difference would be that this would a slow burning bomb rather than a high percussive device. At 40MW/kg (and would need to be much higher than that if you wanted any payload) even if your engine miraculously manages to eject 99% of that energy in the exhaust you still have somehow come up with a way of radiating 400kW for every kg of spacecraft from your engine cooling system. Much greater than 99% actually. And any hot fusion engine requires a driver to initiate the fusion, typically recirculating 0.1-10% of the fusion power output. This one may be self sustaining, requiring no driver, and is not based on hot fusion. Power output regulated by rate of fuel supply. So being insanely optimistic with a Q of 1000 you are recirculating 40kW/kg of space craft power (4GW for a 100 tonne craft), and somehow cooling that power collection and driver systems as well, all for some small fraction of your total mass budget. Then there are the shielding requirements for the vehicle and occupants who are sitting next to this multiple TW output engine and its incredible gamma ray (at minimum) output. If you use D depleted Hydrogen (i.e. near pure Protium), then there will be very little gamma output. Furthermore a small shield just forward of the reactor will cast a large shadow over the rest of the craft. In fact the current multi month missions to Mars that are under consideration may run a larger risk of radiation exposure (e.g. from Solar flares) than a two day fusion powered mission would. Which are just a couple of simple examples as to why anyone with even cursory knowledge of actual engineering knows that what you suggest is so far beyond the feasible that it is quite simply ridiculous. You may turn out to be correct, but it wouldn't cost much to construct a tiny model to see how well/poorly it performs. You seem to be under the impression that I want to construct such a craft immediately. That would be ridiculous. It's an *ultimate* goal, not an immediate one. But perhaps not quite as impossible as you seem to think. 100 years from now it might be possible for a spacecraft to achieve 1% of the power and acceleration levels you suggest at an Isp of 7.5e6m/s, but I wouldn't bet on it. If we don't try new things, it will indeed take a hundred years, or longer. [snip] Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
In reply to Robert Lynn's message of Wed, 6 Jun 2012 23:40:14 +0100: Hi, [snip] http://nextbigfuture.com/2008/12/micro-fusion-for-space-propulsion-and.html At least two differences. 1) There is no explosion, but rather a continuous burn. 2) There is only very minimal photon production (when free electrons very rarely recombine with ions). Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
In reply to Patrick Ellul's message of Wed, 6 Jun 2012 14:10:21 +1000: Hi, [snip] I wrote to Elon Musk offering to help him build a fusion powered shuttle to get us there in 2 days at 1 g with only 20% fuel mass. No response. Funded by marketing it as one big reality show... Possible?? And would you buy a one way ticket to Mars? http://mars-one.com/en/ Regards, Patrick Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Mars One - Humans on Mars in 2023
Realities shows are successful because the success of one relies on the humiliation and exclusion of other participants, like in the old Coliseum. That is not possible in this mission, though, unless you kill passengers, like in the old Coliseum. 2012/6/6 Patrick Ellul ellulpatr...@gmail.com Funded by marketing it as one big reality show... Possible?? And would you buy a one way ticket to Mars? http://mars-one.com/en/ Regards, Patrick -- Patrick www.tRacePerfect.com The daily puzzle everyone can finish but not everyone can perfect! The quickest puzzle ever! -- Daniel Rocha - RJ danieldi...@gmail.com
