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Re: Engineering Newsletter

>> Subject  : Photon energy
>> ReplyTo  : Kevin
>> ReplyFrom: Timothy

>no, I am talking about the momentum of the photons as opposed to the 
>momentum of the ions the "Asimov" will eject as exhaust.  Those will be 
>Hydrogen ions or maybe Xenon moving at .9996 or (.99996, depending on how 
>much energy you can invest) C  at these speeds, a small mass flow is 
>sufficient to slow us down (or speed us up depending on which phase of 
>the mission we are in) at a constant 1 G.

>> This was clear to me, but rethinking this made me 
>> realize that your method can't work. Because adding 
>> momentum to the Asimov will only make it move
>> faster. Transforming it to reverse momentum would 
>> surely break one of the basic physic laws.

No Tim.  The momentum of the microwave is simply added load on the antena
support structure (which is an extreamly unlikely structure) assuming it can
take the load the power (electric) them feeds the engines which use it to
produce forward or backward thrust.  No violation of conservation of
momentum.  As long as the engine is powerful enough (and antenna strong
enough) to overcome the thrust load of the photon sail effect of the big
antenna.  Every thing is fine.

>> Subject  : Solar array
>> ReplyTo  : Kevin
>> ReplyFrom: Timothy

>> But it won't reduce the total solar array, which is really big:

>> Total Solar Power                      : 4E26 Watts
>> Area of a globe with radius 1E9 metres : 7.9E17 square 
>> metres
>> -> Solar power per square metre        : 5E8 Watt

>> Mean amount of power needed by the Asimov : 1E18 Watt
>> -> Size of solar array : 1E18/5E8 = 2E9 square metres
>>                                  = disc with radius 2.5E4 metres.

>> Remember 1E9 metres is quite near Sol. You wouldn't like 
>> to be there in your space suit, because 5E8 Joules would 
>> be added to your body temperature every second.

Are you talking about a 5 kilometer disk a million kilometers from the suns
surface?  Does this not strike you as a servicing problem?

Solar Power Density out here by earth is 1.35 KW/m^2 not the 5E8 Watt/m^2,
but the equipment will be a lot more likely to keep working.

Kelly Starks