Asteroid use

--- In spacesettlers@egroups.com, "Darren Brown: wrote:
>
> Marcel,
>
> Darren Brown: This isn't getting us anywhere, we're just going round and round to
> start all over again. For the record, personally, I'm all for any
> kind of development of space resources, be they planet based or
> asteroid based or something else. That said, I'm of the opinion that
> while all avenues should be explored and used, the one with most to
> offer in terms of cultural variation and human development is the
> large rotating orbital habitat, until something better comes along.
> Having said this I would also want to see the development of
> planetary surfaces but if you start putting people in large numbers
> there, they will begin to object when I want to start ripping up that
> surface to get to the goodies that nature hid there.

MW: Mars would be a great place to make money, IMO. But we have no idea whether it would be a healthy place for giving birth to
babies or raising children or even growing teens with its inherently low gravity. So I would tend to view people who work there
as-- temporary workers-- who would probably only be there to make their fortune over the course of 4 or 5 years. Of course,
you're always going to have some individuals who just love living on such a crazy world. And the low gravity sex might be
interesting? But within 200 years, rotating space islands housing tens of billions of people will probably put most martian
industries out of business, IMO. Ironically, I think tourism on Mars in the 23rd century may swell the martian touring population
into the hundreds of millions (You can only take so much of living the life of luxury on a space island).

>
> Now about putting large and small masses into Cis-lunar space.
>
> DB.
> > On the other hand the small loads of rock
> > attached to light
> > sails would require a less effort to change course
> > at the last
> > moment, a LOT less, a million times less. I feel
> > safe with big
> > rocks, little rocks make me a little uneasy.
>
> MW: The solution is to keep the little rocks and the
> big rocks out of the Terra-Luna system and as we say
> in America 'Let Sleeping Dogs Lie'.
>
> DB: "Let Sleeping Dogs Lie"? With that philosophy you would be still
> living in caves or have horse drawn carts and gas lights. Ignoring a
> problem does not remove it, all it does is make sure you don't see it
> as it hits you in the head. You advocate sending shipments of cargo
> from Mars to Earth. How is 10,000 tonnes of manufactured goods any
> less massive or for that matter any less of a threat than 10,000
> tonnes of rock?

MW: Liquid payloads, of course, would be safer than solid payloads. And if you deliver solid payloads to the Terra-Luna system they
should probably be less than 1000 tonnes in massIn other words, "Don't overload the truck when you're on 'da road".

Darren Brown: Which one is lighter a pound of feathers or a pound
> of steel? If you sent a shipping container or even a convoy of many
> of them, filled with goods with a mass of 10,000 tonnes each (this
> works even better with smaller masses) from Mars to Earth and then as
> it/they swing in close to Earth to bleed off speed before moving into
> a parking orbit you fire a motor hidden in the cargo and the
> container/s coated in it's ablative shielding enters the atmosphere
> before hitting the ground at a speed of 20 Km/Sec, turning the city
> of (insert the city of your choice here) into a smoking ruin. How
> hard is this to do? Well as others have said, not easy, but it is
> doable. Time from start to finish? Well, from months to years
> depending on how you move it.
>
MW: Again, I use lightsails to transport my goods. And if lightsails are eventually made of asteroid material then interplanetary
transportation cost could eventually drop to pennies per kilogram, IMO.

> DB: On the other hand I use light-sails, plasma drive, ion drive,
> bolt on mass driver or what ever I have to begin to move a very large
> and massive rock from the main belt or even better from an Earth
> crossing orbit. I give it small, well timed nudges to move it to
> where I want it. The full fight plan would have been worked out long
> in advance and announced to the world, I have nothing to hid. After
> years or even decades the rock edges up to Earth, now as it closes it
> would be moving at a crawl. Why? Because it takes a lot of energy
> to slow down and the faster it moves the harder it is to stop, the
> slower it moves, the safer it is to people on the ground and if it
> doesn't follow the public flight path, well people will have a lot of
> time to fix the problem or me at lest. By the time the rock is
> reaching it's destination it has maybe passed Earth a few times and
> swung pass Mars and maybe even Venus, with a final swing pass the
> Moon. Now if I had it moving in to its final orbit and as it swings
> pass Earth (if I'm allowed to do that) I fire off a rocket with the
> intention of crashing it into a city/country, I have a huge effort in
> store. If the best I could do to move such a mass takes years to
> move it from start to finish, then I couldn't push it hard enough to
> crash it or if I could the I wouldn't need to, I'd have the
> technology to hit them in a cheaper way. The other problem is your
> small masses (relatively) will be coming with great frequency, one
> per day, one per hour, ten per hour, a convoy of a hundred? My large
> mass would be only once in maybe a decade or maybe even longer for a
> large mass. Yours is hard to keep track of, mine is easy. Bottom
> line, big is safe, small is a potential weapon.
>
> Where have I gone wrong?
>
> > Darren Brown: Next, Mars Vs Asteroid.
> >
> > Sorry Marcel, you have the cart before the horse.
> > You have a couple
> > of problems, first, the delta V needed to move a
> > rock from the main
> > belt to Mars orbit is more than what is needed to
> > move about in the
> > belt. The hook here is the time needed to move
> > about the belt but
> > this is offset by the fact that you could manage to
> > have lots of
> > rocks on the move at once and so could arrange a
> > steady supply of raw
> > material to a given point, Ceres if you like or any
> > other rock that
> > takes your fancy.
> MW: But you forget, that eventually the processed mass
> in the asteroid belt has to eventually end up in the
> Terra-Luna system. But if your goal is to process
> material in the asteroid belt solely for folks who
> live in the asteroid belt then you'd have a point.
>
> DB: I'm sorry, maybe I wasn't clear enough. You want to get your
> raw materials from both Mars and Asteroidal sources, right?

MW: The export of Mars resources to the Terra-Luna system will only be viable-- before-- the exploitation of the asteroids. But
once asteroids begin to be processed in martian orbit, martian resources will then be solely for the martians on the surface who
will operate the orbiting asteroid processing factories from the surface by remote control.

Darren Brown: That is
> what the light-sails were for? Okay, in that case, I wanted to know
> why? You, are talking about two moves, one from the belt and one
> from Mars surface to Mars orbit, where your factories are and then
> after processing being sent to Earth. I was saying that you can get
> all of your needed materials from non-planetary sources and will need
> less energy to move them from source to factory.

MW: While my orbital martian factories will probably initially be made from lunar resources, future factories will, of course, be
made out of the asteroid materials processed in martian orbit.

Darren Brown: You still then have
> to move them to Earth. Now, depending on your method, you may find
> that transport costs are insignificant but I think while this may be
> true for orbit to orbit movements, this will not be the case for
> surface to orbit movements, such as Mars to orbit.

MW: Again, I don't get any resources for the orbital factories from the surface of Mars. The surface of Mars is just a cheap place
for my employees to work with a land area as large as all of the conintents of the Earth combined.

Darren Brown: Of course this is
> predicated on having your factories out at the source of your
> materials. If I've moved my very large mass into an L4 orbit then
> all comparisons are moot. My workforce is happy living in Island 3
> and working on the large rock we've just moved in next door. When
> ever you talk about doing things in space you must remember the
> golden rule, once you are in Earth orbit, your half way to
> everywhere. Going back down to a planets surface is just crazy, it's
> like driving with the brakes on!! Even using robotic equipment with
> tele-present operators, Mars makes no sense, you could do the same
> from Earth to Earth orbit and I think I shown that you can move your
> raw materials into a safe orbit.

MW: Mars orbit makes a great deal on sense since you'll already have martians on the surface ready to remotely operate orbiting
factories. I see asteroid processing happening around 2030.
>
> Darren Brown: A few times you have mentioned
> > that Mars has all
> > the materials needed to build a base so you could
> > live off the land
> > while building your infrastructure. What can you
> > obtain from the
> > Martian (I'm not sure about Marsian, I have never
> > heard it before, is
> > it something new?) resources that you can not get
> > from asteroids or
> > comets? Answer, nothing!
>
> MW; Again, because of its significantly larger gravity
> it is much easier to live on the surface of Mars than
> it is to live on the surface of an asteroid.
> Microgravity environments are already known to turn
> off the immune system and to deplete calcium in the
> bones. And the gravity of Ceres is significantly lower
> than on the Earth's moon. Your health cost and your
> labor cost are going to be very high compared to
> someone working on the surface of Mars.
>
> DB: Please, this not the question I asked. Again, I ask, what
> resource can you get from Mars that you can not obtain from non-
> planetary sources?
>
MW: A natural gravity of one third that of the Earth with a land area equal to that of the land area of the Earth. No asteroid has
these natural attributes which are essential for my labor force.

> DB: As for your point about gravity, we don't know if 1/3 G over the
> long term is any better than micro G. It is possible that people can
> no more live in 1/3 G for a long period without health risk than they
> can in micro G. For my part I think it would make a difference but
> it may have other effects that we don't know about, maybe 1/3 G is
> okay for years or maybe forever, there is only one way to find out
> and I want us to know but that is a different from setting up house
> on Mars. But as for my workforce, I never considered that they would
> live on the surface of the asteroid, however you are very wrong about
> the surface of a large asteroid being the same as micro G. The NEAR
> probe is in orbit around Eros, how do you do that in Micro G? There
> is very much an up and down, you can just overcome it with ease.
> This does raise a very good question though, if the, let's say 1/50 G
> of Ceres (I'm not sure that it is 1/50 but it's a good a number as
> any for this point) is not able to keep people healthy but the 1/3 G
> of Mars is, where is the cut off point? Personally I don't think
> there is one, just that some people will be able to take lower G
> without trouble for longer than others and that anything less than 1G
> will cause problems for some while other will benefit from less than
> 1 G. But I wasn't going to put my workforce on the asteroid surface
> anyway so this is of academic interest only.
>
> Darren Brown: Your other big problem is
> > a legal one,
> > forget your ignorant masses the problem is in a few
> > UN treaties, they
> > stop you from claiming any celestial body. You
> > start digging up Mars
> > to build your bases and you will find researchers
> > running around
> > yelling for blood. They will point to you
> > contaminating the
> > environment and ruining the research possibilities.
>
> MW: Since researches would need to have a base in
> order to survive on Mars in the first place that would
> be like saying "Please kill me, I shouldn't be here."
> Besides I believe that there should be an
> international 'Natural Wonder' law that does not allow
> and country or business to exploit or to lease more
> than 1% of the surface area of a planet or an asteroid
> 100 kilometers in diameter. And even on tiny Ceres
> that would mean that several thousand square
> kilometers of surface area would be available for
> exploitation. And with the exception of the Earth
> grazers, I see no reason to exploit asteroids larger
> than 2 kilometers in diameter and smaller than 100
> kilometers in diameter. These are natural wonders
> that should be left alone, IMO. The limited
> exploitation of the largest asteroids and the billions
> of smaller asteroids that range from 1000 tonnes to
> over a billion tonnes each should be enough to build
> all of the space colonies that we'll ever need in the
> solar system.
>
> DB: True researchers work in the Antarctic without problems but they
> also don't open mines. Is there a difference between an operation
> that has a Mars with 10 research bases and an operation that has a
> Mars with 10 research bases and 20 mines? Having research bases and
> having mining operations are very different. Mind you, I think Mars
> should be allowed to be mined, providing there is no special reason
> not to. If you landed your expedition and found life there, we have
> a major ethical problem, do we have the right to upset the
> environment containing a native life form? How long do we have to
> look before we can say there are no native life forms? How do we
> keep our life forms from contaminating the local environment? These
> are questions that really should not rise with respect to asteroids,
> at lest not as we understand things at the moment.

MW; I have no problem with mining on Mars as long as long as 99% of the surface is left unexploited. That of course would-- only-
-- give you about 4 million square kilometers to exploit. And I doubt that even 400,000 square kilometers of martian surface will
ever be exploited.

>
> DB: A natural wonder law? Please tell me you are kidding! Your
> limits are arbitrary and without any reason other than people like
> round numbers. Why 2 Kms and 100 Kms? If a particular rock has some
> kind of merit or there is something special about it, fine, there are
> lots more out there but just because it's less than 100 Kms wide?
> Chances are that a billion years ago it was more than 100 Kms wide
> but time has chipped it down to size, I can't use it just because I
> wasn't around a billion years ago or how about I see a 20 Km wide
> rock that I want, if I throw a few 200 metre rocks at it can I use
> the parts I chip off, they should be smaller that 2 Kms and if not
> I'll just keep throwing rocks until it is. Madness.
>
MW: Again, all the material you will ever need for space colonies (enough to house about a trillion people in the solar system)
could be easily found by processing asteroids less than 2 kilometers in diameter. And small asteroids are a lot easier to process
than large asteroids. And I do allow the processing of all asteroids (no matter their size) that are a potential hazard to the Earth.
And I do allow 1% of the surface area of celestial bodies larger than 100 kilometers in diameter to be exploited. But these larger
asteroids are going to be great tourist attractions in the 22nd century IMO. Folks may even visit some of them in their own private
lightsails.

Marcel F. Williams
1/9/01