🚀 go-pugleaf

-From: roberts@cmr.ncsl.nist.gov (John Roberts)
-Subject: Re: Next unmanned missions to Venus
-Date: 25 Jan 93 03:35:22 GMT

--From: rkornilo@nyx.cs.du.edu (Ryan Korniloff)
--Subject: Re: Next  unmanned missions to Venus *
--Date: 24 Jan 93 06:39:04 GMT
--Organization: University of Denver, Dept. of Math & Comp. Sci.

--Hmmm, well, I guess if we were to make any kind of serious exploration of
--Venus's  surface we would have to develop electronics componants that
--operate comforably at 900f. And metals that can protect the inards of the
--probe from terrential sulfuric acid down-poors..
--How WOULD we do that by the way? Anyone know??

-Read the October 1992 Scientific American. If they pan out, diamond film
-semiconductors should be able to operate at up to 700 C (as compared to
-than silicon semiconductors.

Change that last paragraph to read:
"Read the October 1992 Scientific American. If they pan out, diamond film
semiconductors should be able to operate at up to 700 C (as compared to ~450 C
at the surface of Venus), and should be smaller than and operate 40-100 times
as fast as silicon semiconductors."

Other measures that I've proposed in previous years:
 # Nuclear reactor (or RTG, as recently proposed by Kevin Plaxco), driving
   a heat engine, which powers a refrigerator.

 # Tethered balloon, with temperature differential between the ground and
   the balloon driving a heat engine. This has the advantage of not needing
   an imported energy source. I haven't looked at the numbers lately, but
   I *think* the temperature differential is great enough that you might
   be able to get useful power from a tether on the order of 10 km high.
   The high density of the atmosphere would be useful, if the tether is of
   fairly low density. Wind speeds are reported to be very low near the
   surface, and very high in the upper atmosphere. I don't have a velocity
   profile that could be used to calculate wind speeds 10-30 km up.

   What to fill the balloon with to make it buoyant is an interesting
   question. If the fabric is non-flammable, oxygen extracted from the CO2
   atmosphere is a possibility. (The fabric would have to be totally resistant
   to further oxidation.) If the heat flow is great enough, it might be
   used to lift a hot-CO2 balloon.

John Roberts
roberts@cmr.ncsl.nist.gov