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Re: NASA proposes artificial magnetic field to make Mars a second home

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On 3/11/2017 3:54 PM, Dr J R Stockton wrote:
> In sci.astro message <o9p3o5$1gve$1@gioia.aioe.org>, Wed, 8 Mar 2017
> 08:16:28, S Ergio <invlid@invalid.com> posted:
>
>> On 3/8/2017 6:42 AM, Yousuf Khan wrote:
>>> http://www.zdnet.com/article/nasa-proposes-artificial-magnetic-field-
>>> to-make-mars-a-second-home/
>
>>>> Green proposes that by placing a magnetic dipole shield at the Mars L1
>>>> Lagrange Point, a man-made magnetosphere sphere would cradle the
>>>> entire planet.
>
> Sort of.  The dipole would shield the dayside of the atmosphere of Mars
> from the solar wind.  By the way, in the past, at least some respected
> authors called L1 "L2" and L2 "L1".  The proposal is not by Green; it is
> by Green /et al/.
>
>> how far away is Mars L1 Lagrange Point from Mars ?
>> about 141,000,000 miles.
> Very wrong.
>
>> how does magnetic field strength decline with distance ?
>> 1/d^2  ?
> For that, you need a monopole source.  Point-dipole fields go as d^-3.

no, the fields vary as d^n  where n is between 2 and 4, and n is also a 
function of d, and orentation of the field.

>
>> so you need a magnet of at least 2*10^16 telsa ? ?
> The field strength at the magnet is of itself not important.  It is the
> dipole moment which creates the far field.

field strength is *the key* design requirement, it drives the rest of 
the design.

  Referees should not have
> accepted <http://www.hou.usra.edu/meetings/V2050/pdf/8250.pdf> as it is,
> on those grounds.
>
>> why not just put it on the surface ? by the way, you will have to water
>> cool it too.
> Because that is a different, and not useful, idea; superconductors were
> discovered about 11 decades ago.  Use currently-available high-
> temperature superconductors or better,

cooling is to lower copper coil losses, high temp superconducters are 
not yet reliable for this, unless you have a url to a 1 T magnet using 
one...

  I think it gets down to watts, if 100 W it probably could be done, if 
2000, probably not.


> and cool by shades as will be
> done for JWST;
allow the magnet to cool by radiation into the rest of
> the Universe.

but all that is limited by # Watts used, and if it is in sunlight, which 
it is.

>
>
>> extra credit questions;
>>
>> 1. how much water is needed to cool magnet that generates a 1 T field
>> 100,000 miles away. (how is this water stored?)
> None; why 100,000 miles, as according to you L1 is at 141,000,000 miles.
> (in a zero-litre container).

you evade the question, how much heat is generated by the super-cooling 
refrigeration unit for a 1 T field at 100,000 miles ? ( leave "T at 
100,000 miles" as a variable)  How many Watts does will the 
refrigeration unit take to keep the unit cool?  how many solar panels ? 
how much storage capacity is needed ?  How much refrigeration fluid is 
lost each year ?  (NASA has supercooled stuff in flight, limited life 
time due to fluid loss)

>
>> 2. how much electricity in megawatts is required to run magnet, then to
>> pump water.
> None.  But energy will be needed to create the dipole moment initially.

not so, see above, [Im sure NASA has info on this, effecient 
supercooling refegeration, not sure about application to a magnet, but 
they probably have a study on it]

>
>> 3. what % of partials will be deflected away and outside a 100 mile
>> zone on the surface around the magnet? (assume 98% speed of light)
> Wrong question.

yep, wrong question to you, as you do not have any answer.

>
>> 4. What type of partials will be hardly by magnet ?
> Parse failure.  Try writing in your native language.

you engrlish teacher ?  this is physics group.

>
>>>> While Green admits the idea is somewhat "fanciful,"
>>
>> this dude works at NASA ???
>
> Why not?  NASA must have canteen staff, toilet cleaners, and PR people.
> But the esteemed originators should not be criticised for the failure of
> /hoi polloi/ to understand their published proposal, and perhaps to read
> it.

  need more engineering before reclassifying from pipe dream to possable.

> The proposal is to deflect the solar wind, without adding energy to it.
> Therefore, the wind will press the magnet outwards; the magnet must be a
> little inwards from L1, because of that and of radiation pressure.
>

which directly goes to what the field strength should be, .

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Thread

NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-08 07:42 -0500
  Re: NASA proposes artificial magnetic field to make Mars a second home S Ergio <invlid@invalid.com> - 2017-03-08 08:16 -0600
    Re: NASA proposes artificial magnetic field to make Mars a second home dlzc <dlzc1@cox.net> - 2017-03-08 06:21 -0800
    Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-08 11:40 -0500
      Re: NASA proposes artificial magnetic field to make Mars a second home S Ergio <invlid@invalid.com> - 2017-03-08 11:51 -0600
        Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-08 22:44 -0500
          Re: NASA proposes artificial magnetic field to make Mars a second  home The Starmaker <starmaker@ix.netcom.com> - 2017-03-08 23:36 -0800
            Re: NASA proposes artificial magnetic field to make Mars a second  home The Starmaker <starmaker@ix.netcom.com> - 2017-03-09 10:07 -0800
          Re: NASA proposes artificial magnetic field to make Mars a second home S Ergio <invlid@invalid.com> - 2017-03-09 08:47 -0600
            Re: NASA proposes artificial magnetic field to make Mars a second home "Rodney Pont" <mlist4@infohit.me.uk> - 2017-03-09 16:21 +0000
              Re: NASA proposes artificial magnetic field to make Mars a second home S Ergio <invlid@invalid.com> - 2017-03-09 10:50 -0600
                Re: NASA proposes artificial magnetic field to make Mars a second home "Rodney Pont" <mlist4@infohit.me.uk> - 2017-03-09 19:04 +0000
                Re: NASA proposes artificial magnetic field to make Mars a second home S Ergio <invlid@invalid.com> - 2017-03-09 15:31 -0600
                Re: NASA proposes artificial magnetic field to make Mars a second home "Rodney Pont" <mlist4@infohit.me.uk> - 2017-03-10 05:43 +0000
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-10 01:42 -0500
            Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-09 21:37 -0500
              Re: NASA proposes artificial magnetic field to make Mars a second home "Rodney Pont" <mlist4@infohit.me.uk> - 2017-03-10 05:38 +0000
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-10 01:51 -0500
                Re: NASA proposes artificial magnetic field to make Mars a second home "Rodney Pont" <mlist4@infohit.me.uk> - 2017-03-10 07:21 +0000
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-10 08:24 -0500
                Re: NASA proposes artificial magnetic field to make Mars a second home dlzc <dlzc1@cox.net> - 2017-03-10 06:37 -0800
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-11 15:58 -0500
                Re: NASA proposes artificial magnetic field to make Mars a second home dlzc <dlzc1@cox.net> - 2017-03-11 18:09 -0800
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-13 01:13 -0400
                Re: NASA proposes artificial magnetic field to make Mars a second home dlzc <dlzc1@cox.net> - 2017-03-13 07:14 -0700
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-15 23:41 -0400
                Re: NASA proposes artificial magnetic field to make Mars a second home dlzc <dlzc1@cox.net> - 2017-03-16 07:25 -0700
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-18 04:10 -0400
                Re: NASA proposes artificial magnetic field to make Mars a second home dlzc <dlzc1@cox.net> - 2017-03-18 09:05 -0700
                Re: NASA proposes artificial magnetic field to make Mars a second home Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2017-03-19 20:41 -0400
    Re: NASA proposes artificial magnetic field to make Mars a second home Dr J R Stockton <reply1700@merlyn.demon.co.uk.invalid> - 2017-03-11 21:54 +0000
      Re: NASA proposes artificial magnetic field to make Mars a second home Serg io <invalid@invalid.com> - 2017-03-12 11:52 -0500
  Re: NASA proposes artificial magnetic field to make Mars a second home The Starmaker <starmaker@ix.netcom.com> - 2017-03-08 10:38 -0800

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