[extropy-chat] Pluto New Horizons launch -getting ready

[Robert Bradbury]

Spike your thinking is still stuck in the "standard model".  (I.e. you have
to decelerate to "land").  Screw that.  Let the damn planet absorb the
momentum, it isn't like its going to alter its orbit significantly.  Think
something like a spacecraft with a bunch of nanotubes between it and the
planet (we can grow buckytubes now!).  Now you can get into a complex
discussion as to whether you want layered nanotube mesh fabric (horizontal
orientation) or end-on nanotube columns (vertical orientation).  Look up the
mass of the New Horizons satellite is (you folks should know this right --
you *did* lauch the thing).  Figure out the total energy of it hitting Pluto
then figure out what quantity of nanotubes/buckyballs you would have to
vaporize to throw away the energy.  Nanosystems says the C-C dissocation
energy is 0.545 aJ (pg 52).  How many C-C bonds would you have to break to
offset the impact energy?  Yes, I know you need a heat shield to protect it
from that but the Stardust probe managed ok.  What you really want is a
collapsible shield structured so that most of the impact energy goes out
sideways rather than back towards the spacecraft.  Ok, now expand on that
concept a little bit.  Say you have the carbon nanotubes/buckyballs filled
with H or He (lightweight and will absorb some of the impact energy and
dissipate).

Then there is the question of how many g's a "hardened" satellite can really
withstand?  If you structure it so it is strengthened for impact I suspect
it quite high.

I get the feeling there is a NIAC study hidden in this topic that could be a
lot of fun.

Also, I'm reasonably certain Pluto does have an atmosphere (though thin) at
this point in its orbit so some form aerobraking could be feasible (though
it may not be worth the effort).

Finally, current micro chip scales *are* nanotech.  It still comes back to a
question of how many g's they can withstand on impact and what kinds of near
term nanotech can be used to reduce the impact they must withstand.

Robert
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