| Subject: Re: SETI and The Fermi Paradox |
| From: BradGuth |
| Date: 20/09/2009, 21:34 |
| Newsgroups: alt.atheism,sci.astro.amateur,alt.sci.seti,alt.astronomy |
On Sep 20, 12:40 pm, Andrew Smallshaw <andr...@sdf.lonestar.org>
wrote:
On 2009-09-20, Morten Reistad <fi...@last.name> wrote:
We only have three materials we have knowledge of for such
high pressure use. Steel, Aluminium 6xxx series and kevlar
epoxies. All of these corrode within seconds on Venus.
This is of course why the crew of the Trieste were instantly killed
when they reached the bottom of the Challenger Deep. They didn't
know what you do and so the observation window, made out of nothing
more than Perspex, gave way immediately.
Oh, hang on, that didn't happen, did it?
The whole notion of only certain materials being good enough when
the only issue is sheer strength is a complete non-starter. You
could make a pressure hull for the pressure in question using
nothing more than papier mache if you were so inclined. Such a
hull would be extremely thick and weigh many times what it really
needs too, but that does not mean that the exercise is completely
impossible or even particularly unfeasible.
As for corrosion resistance that is a separate issue to withstanding
the pressure. Since you give steel as an example we'll consider
that. Left to itself corrosion would indeed be a major concern.
That does not mean that it can't be used: give the hull a generous
plating of e.g. gold or titanium after it has been constructed and
there are no real issues: the steel takes the strain but is nicely
protected from the elements.
Nightcrawler <Dirtyde...@dirtcheap.net> wrote:
In fact, anything sent there dies. Machine or biological.
Even that is a bit of an overgeneralisation. Cooling for a manned
compartment would indeed be a formiddable task but machines operating
at ambient temperature are much more practical. Silicon based
electronics is out but valve based systems will take the temperatures
needed in their stride.
--
Andrew Smallshaw
andr...@sdf.lonestar.org
That's actually a very good response. Too bad that these folks in
charge of mainstream enforcing are only going to go out of their way
in order to topic/author stalk, bully and trash anyone that doesn't
agree with their anti-Venus and especially with their anti-Guth
mindset and official policy of obfuscation and denial.
As hot and nearly crystal dry as the geothermally active surface
environment of Venus is, including the vast bulk of its atmosphere
below those acidic clouds, the toasty environment is rather corrosion
inert or passive.
Heat exchanging is not technically insurmountable, especially when
there's essentially unlimited local renewable energy to burn (so to
speak), and all of that nifty atmospheric buoyancy that'll float damn
near anything isn't exactly something to sneeze at.
Your titanium clad steel is also a good one, not that corrosion is a
significant problem as long as these composite rigid airships operate
extensively below the lower cloud haze.
~ BG