Ok, radiation shielding is necessary *anywhere*

From: "Darren Brown"
To:
Sent: Thursday, October 19, 2000 3:07 AM
Subject: [spacesettlers] Re: Ok, radiation shielding is necessary *anywhere*

> Salutations,
>

Salutations,

> One point before I reply. First I must admit to a mistake, I called
> it a Mass Coronal Ejection, a look at the space weather site attached
> to NASA tells me that it's a Coronal Mass Ejection, a CME not a MCE,
> a
> minor point but I really don't like to pass on faulty data.
>

Seems the same to me (order of adjectives in English always seemed
irrelevant to me, but maybe that's just because I'm not a native speaker);
anyway, ok, lets use CME from this point on.

> It seems that you and I are the only active people in here, how
> disappointing.

Indeed. Well, I received a message from another guy, nicknamed "Seagull",
but he never posted anything more again. The case is that this group is
somewhat recent and I made no effort to advertise it. Hummmmmm... Perhaps if
I put it in my signature, though that perhaps would not be *that* useful: I
am also a member of a science list and a skeptics list - for Brazilians -
and I would have to catch the attention of someone who at the same time
likes the subject of space colonization and also feels comfortable writing
in English - not a much frequent combination. By the way, do you participate
on any other lists/newsgroups with interests intersecting space
colonization? Maybe it would be easier for you to find more potential
members for our list.

> Tell me you have called this "Spacesettlers", I
> assume
> from that you are mostly interested in the human settlement aspect of
> space exploration?

Indeed. With a special emphasis in space settlements/habitats. I'm kind of
skeptical about terraformation projects, for example, though I try to keep
myself open minded to them.

> Don't get me wrong, given a magic wand I would
> spend the worlds military budget on getting us (the human race in
> general) into a multi-planet/habitat situation. Just consider how we
> currently have all our eggs in one basket. All it would take is a
> single large lump of cosmic flotsam and even with twenty years notice
> we still might not be able to do anything. In fact politics,
> religion, the laws of physics and human nature could effectively
> undermine any attempt to save ourselves. To that end the more places
> we are the lest chance of any single, natural disaster putting a stop
> to us.

Yes, yes... It is pretty weird how *everyone* seems to be completely unaware
of the fragility of the human race right know. I also have this sense of
urgency regarding space colonization, but I think that it will take decades
(or even a couple of centuries) for the first off-Earth human settlements
actually exist. I'll be happy if I just see during my lifetime the raise of
some cheap way (a few tens of thousands dollars per ticket ;-) to get into
LEO...

> I was just wondering about your interests, your pseudonym
> "DrOmni" would indicate a wide ranging interest, it would help to
> know
> if I was talking to a specialist or a polymath.

Your guess is right, I'm a generalist. (I prefer that term to "polymath",
which seems to imply that I would have enciclopedic amounts of knowledge
inside my head...) "Dr. Omni" was a nickname given to me by a friend at the
University, because he was used to say that I knew a little bit of
everything; it stuck, and it is the name that I prefer to use in the
Internet. Unlike many internet pseudonyms, it is not a "cover" for hiding my
real name, Lucio de Souza Coelho - it's just a matter of preference, really.

> The wonders of the
> internet, I sit in my office in Australia and try to decide how to
> answer a post from Brazil, not a simple thing. What to say. well
> here
> goes.
>

;-) I chose to create an *international* mailing list because I was
surprised to see that there is *no* list at e-groups dealing with space
habitats - although there are many lists dealing, for example, with
terraformation. It seemed that space habitats are not a very popular
subject - people seem to be too used to living in a planet, and too
brainwashed by decades of science fiction movies and shows with characters
living on planets, to like the idea spacehabs (actually, most of the people
that I know does not even know that concept). Therefore, I thought that I
would need a big enough human mass to get participants on the group - so I
chose English (the international language) as the official language for the
list.

[snikt]
> Yes, you do seem to like drills, while I think a big hammer is
> cheaper, not better, just cheaper.
>

But would the "hammer method" really be that cheap? You would need a
monstrously big electromagnetic mass driver or other mammoth propulsion
system to deflect the orbit of a big asteroid; it is not evident for me why
that would be cheaper than a mirror with a monstrously large surface
(although probably a few micrometers thick).

> The gas giants are really big so there is a lot of room to put power
> plants but it occurs to me that I read that some of Jupiter's inner
> moons were in fact inside the magnetosphere. If that is the case
> then
> all you need do is cover the surface with wires and sit back.
>

Yes, Io is deep inside the magnetosphere and in fact some of the phenomenal
internal heat of that moon is generated by Joule Effect, caused by Jupiter's
magnetic field inducing electric currents through the moon. Maybe even
Europa is deep inside the magnetosphere, but I don't know for sure...

[snikt]
> The moon is a lot closer that Jupiter or Uranus, a good place to
> start, in fact the moon is a good place to build a large fusion
> reactor, if anything went wrong, well there isn't a lot they could
> damage, is there. But you should have a look at
> http://antimatter.phys.psu.edu/documents.html . This group have also
> been reported on in Science and New Scientist
> http://www.newscientist.com/home.html and on the NASA site.
>

I think that antimatter is perhaps the key to deep space travel, but it is
worth to remember that antimatter is not a *source* of energy, it is an
extremely efficient *storage means* for energy. But you need to spend lots
of energy to create antimatter, and that energy would have to come from some
natural (Sun, electric tethers, etc) or artificial (fusion reactors) source.

[snikt]
> Yes but I don't know if I would be quick to volunteer, the Chinese
> satellite program has been threatened with having its insurance
> revoked due to the number of launch problems, including total
> destruction of the rocket. Don't know if I'd feel safe enough.
>

Indeed, the Chinese now are like the Americans in the early 60's, blowing up
a rocket after the other. Building a vehicle that works in extreme
conditions like a space rocket is not an easy task, and is also a technology
that is normally kept secret (due to its utility in building
intercontinental missiles). At least, the Chinese are a bit more advanced
than we Brazilians - we have tried already two or three prototype satellite
launch vehicles along the last year or so, and all of them failed for one
reason or another.

> Darren Brown
[snikt]

Dr. Omni
ICQ# 53853815