XPost: sci.space.policy, sci.optics, sci.physics   
   XPost: sci.military.naval   
   From: fjmccall@gmail.com   
      
   "Robert Clark"  wrote:   
      
   >"S??gi ?"  wrote in message news:oibn46$tjp$1@gioia.aioe.org...   
   >========================================================================   
   >On 6/20/2017 12:31 PM, Robert Clark wrote:   
   >> "Robert Clark"  wrote in message news:oi3a88$nck$1@dont-email.me...   
   >>   
   >> At the distance of the Parker probe, a 1 km sq. mirror could collect a   
   >> terawatt of power for beamed propulsion or space solar power beamed to   
   >> Earth.   
   >   
   >>   
   >> The Parker probe will use a refrigeration system to lower the temperature   
   >> of   
   >> the components of the spacecraft from 1,400 C to room temperature. This is   
   >> about the same temperature drop as the temperature drop from the Sun’s   
   >> surface to the maximum temperature of our high temperature ceramics. So it   
   >> should be possible to do this temperature drop on the surface of the Sun   
   >> using our highest temperature ceramics.   
   >   
   >refrigeration wont work. if reflectivity is 99.9% you still ave to move   
   >how many terrawatts(?) from front to back of the spacecraft, AND radiate   
   >that out to cold space on the backside ??   
   >   
      
   He wasn't speculating, Bob.  That is what the Parker Probe is going to   
   do.   
      
   >   
   >also Gamma rays are going to cook it, +fry electonics.   
   >what are the gamma ray radiation levels close to the sun ?   
   >   
      
   If you don't know the gamma ray levels, how can you say gamma will   
   cook it?   
      
   The gamma ray flux outside the surface of the Sun is essentially zero.   
   It all gets converted to visible photons from 170,000 years of   
   collisions inside the Sun on its way to the surface.   
      
      
   --   
   "Ignorance is preferable to error, and he is less remote from the   
    truth who believes nothing than he who believes what is wrong."   
                                  -- Thomas Jefferson   
      
   --- SoupGate-Win32 v1.05   
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