XPost: sci.space.policy   
   From: rijrunner@frii.com   
      
   Bill Bogen wrote:   
   > Charles Buckley  wrote in message news:<40   
   857d0$0$70309$75868355@news.frii.net>...   
   >   
   >>Oren Tirosh wrote:   
   >>   
   >>>wbogen@visteon.com (Bill Bogen) wrote in message news:...   
   >>>..   
   >>>   
   >>>   
   >>>>4) Once on the Moon, use the rover to explore possible lava tube   
   >>>>sites.  A simple and inexpensive inflatable structure can be quickly   
   >>>>set up later in a lava tube since the structure will only have to   
   >>>>retain air pressure, while the lava tube itslf will provide meteor,   
   >>>>radiation, and thermal protection.   
   >>>   
   >>>   
   >>>I agree that lava tubes could make a huge difference for the viability   
   >>>of a lunar base. Our ancestors took shelter in caves. There's no   
   >>>reason why we shouldn't have lunar cavemen. But finding such lava   
   >>>tubes could be tricky. A rover has very limited range and speed. You   
   >>>have to scout for likely sites first.   
   >>>   
   >>>   
   >>   
   >>   
   >>   You can always dig a hole.   
   >   
   >   
   > How, exactly?  A low cost mission won't include a massive backhoe.   
   > Explosives?  We'd still have to move lots of rubble.  By hand, with a   
   > shovel while wearing a pressure suit?  Much better to set up a roomy,   
   > inflatable permanent base quickly in a lava tube, even if we have to   
   > drive/send rovers 100s of kms to interesting sites.   
   >   
      
      
      Mostly, it would be more a case of finding a place where there   
   is an existing depression or hole such as a crater or rille. Then,   
   adding a bulldozer attachment to the rover and just scrape over the   
   surface. there were a number of suitable sites near all of the Apollo   
   landing sites which indicates that the condition is common to the   
   moon.   
      
   >   
   >>The big enabler would be water resources.   
   >>That will drive site selection and tech development.   
   >   
   >   
   > Another post states that the interior of lava tubes is probably at a   
   > constant -21 degrees C.  Comet impacts on the Moon could well have   
   > flung some ice/water vapor down a lava tube where it condensed.  This   
   > is one resource our rover could look for.  For a technical reference,   
   > see 'The Adventures of Tin Tin: Destination Moon' by Herge.   
      
   That odds of that are essentially zero. Most of the hypothesis for water   
   on the moon are based around solid water deposits being flung around.   
   Water vapor would remain gaseous in the lunar environment. Vapor   
   spreads evenly around the entire moon, from what they determined from   
   the Apollo expirements, then is swept away. The vacuum of the normal   
   environment would essentially evacuate any tube prior to any   
   condensation.   
      
   --- SoupGate-Win32 v1.05   
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