Anthony:
:)
I’m pretty sure that nuclear weapons codes have been modified to simulate
both p-p and carbon cycle stars; heat transport included.
In some great detail. Using pretty nearly the best supercomputers in the
world. Decades ago and rather more recently.
On the basis of those simulations; I’m pretty sure the story of how long
heat transport takes in stars is well understood among those who are read
in.
Just sayin’.....
Bill
On Tue, Mar 10, 2020 at 6:07 PM Anthony Cesaroni <anthony@xxxxxxxxxxx>
wrote:
Al Gore.
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
(941) 360-3100 x101 Sarasota
(905) 887-2370 x222 Toronto
*From:* arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> *On
Behalf Of *Christopher Buchanan Shay
*Sent:* Tuesday, March 10, 2020 7:19 PM
*To:* arocket@xxxxxxxxxxxxx
*Subject:* [AR] Re: Freeman Dyson, RIP
Who was it proposed a hybrid inflatable sail that would not be unfurled
but simply blown up like a soap bubble inside a magnetic field? It was
supposed to use photons as well as plasma? I believe the technical hitch
was...the hitch to the vehicle itself. Was it a weak M2P2 field, sticky
enough to maintain a solar bubble in space?
Can’t find a reference...Maybe there isn’t one. :-)
On Tue, Mar 10, 2020 at 6:17 PM David Summers <dvidsum@xxxxxxxxx> wrote:
The reason to cover the entire sun is so that you can use the sphere as a
solar concentrator as well. That way you don't have to have the entire
surface covered in solar cells. Of course, it would probably be a bad idea
to do this to your own star, as it would get either mighty bright or mighty
dark here on Earth. So you would borrow a neighbor's star, and who cares if
it does "bad things" to the star.
New SF novel - the aliens come here, but ignore Earth and just build a
sphere around the sun!
Thanks!
-David Summers
On Tue, Mar 10, 2020 at 10:55 AM Norman Yarvin <yarvin@xxxxxxxxxxxx>
wrote:
On Tue, Mar 10, 2020 at 04:19:18PM -0400, Henry Spencer wrote:
On Tue, 10 Mar 2020, Norman Yarvin wrote:will
...the message will get through eventually. If the
outer layers get hotter and hotter, eventually the outward heat flow
notstart to slow, and the core temperature will start to rise.
Still, the core temperature of the sun is millions of degrees.
Raising the surface temperature by a mere thousand degrees would have
a hard time changing it significantly.
If you've enclosed the whole thing in a mostly-reflective sphere, it's
going to stop with a mere thousand degrees. Given time, temperatures
inside the sphere will rise until either radiant heat emitted outward by
the sphere equals energy generation inside, or something breaks (e.g. the
sphere starts to melt and disintegrates).
I'd bet on the manmade thing (or even the men themselves) breaking
before the sun did. Why would anyone try to be that thorough, though?
Leave out half the area, and a thousand degrees is about right for the
temperature rise. (T^4 scaling, and a starting temperature of 6000 K)
For that matter, a reflective sail doesn't have to point the radiation
directly back at the sun; it can miss it by a bit and get hardly any
loss of thrust. Indeed, it's probably easier to miss than to hit.
That won't work with a complete sphere, but could reduce the impact
from covering half the sphere to nearly zero.
--
*Christopher Buchanan Shay*
*(321) 443-1451*
*"One today is worth two tomorrows."-**Benjamin Franklin*