Conference 7.286::space

  Sorry I can't tell if you are joking or not so I'll try to keep it short. No,
things don't just cost into the sun, it takes quite a bit of energy to slow
things down enough to get them into the sun. 

  Also, most launchers have a 95% success rate which means 5% of them crash
somewhere or other on earth. 

  Maybe some day when launchers are 99.99% successfull (not in our life time)
and nuclear powered space tugs are available, ...

  George

    Space as "landfill", taken to a logical extreme, implies reducing the
    mass of the Earth until there is nothing left.  Spurious notion.  This
    points out the added importance of recycling, and designing with
    recycling in mind.

I like this idea.   But to make it work, you'll have to make sure that the
cost of disposal (which will be - to coin a phrase - astronomical) must be
included in the life cycle costs of the things we purchase.

Right now it's too cheap to dump things in the ocean, spare land, air, etc.
By adopting this "space" approach, we have a unified way of getting rid of
trash - with a fixed cost basis.

Figure the cost of normal trash items - like paper, plastic, metal, etc. - will
increase by a factor of maybe 10 (e.g., that polystyrene-enclosed burger will
now cost $12).   Dangerous byproducts that require those "ultra-reliable"
launchers may go up by a factor of 1000x  -- to figure out what that will
affect, just look around your house for any articles whose manufacture may
involve toxic chemicals (or nuclear reactions :-)).


By making people actually pay for the disposal of their trash -- perhaps
they'd produce a little less of it.


- dave

p.s. I could think of about 100 reasons why .0 won't work  --- I thought it
a challenge to find one reason why it should.

    Re:.0
    
    	This is yet another example (taken to the extreme) of our society's
    "throw away" mentality. While at this point in time such a space based
    disposal method would be far too expensive to be economicly feasable
    one could imagine the day when launch costs decrease enough and other
    means of disposal become too expensive making this option viable.
    Instead of continuing this never ending spiral of manufacture it/use
    it/dispose of it I think it would be to our advantage to start thinking
    in terms of recycling and developing a way of thinking in manufacturing
    in which if one makes a product and the wastes cannot be reused or
    destroyed in an enviromentally safe way, you don't make the product to
    begin with.
    
    				Drew
    

Just think of these landfills as the resources of the future. At some point it 
will become advantagous to "mine" the old landfills for the "trash" that we are 
wasting. I don't think it will catch on to "toss" our resources into the "solar 
furnace"

These trash deposits have a higher concentration of specific elements that 
typical "ore" already ;^)

Hello again,

CAUTION: I'M attempting to make sense of my original note.
 

My idea is not to send normal trash but the really dangerous stuff that 
we can't figure out how to dispose of here to the Sun to be incinerated.
We have alot of nuclear power plants that are being decommissioned as 
well as TMI and the Chernobel (sp?) that have to be really disposed of
somewhere. I recall in the early 60's the idea was that by the time this
was going to be a problem we would have developed technology to dispose 
of these things. Well we are there! Cher*.* is cooking away, all the 
nukes that have spent fuel rods and all this has plutonium in them and
that'll never go away. Its a problem like none of the other trash we've
made because this nuke trash really could make this world unlivable at
anytime before it goes away in 100,000 years. Or we could send it to
the Sun and let the Sun's heat do the job.

Fred Mudgett

  How do you recycle plutonium?

  Yes the sun would be a fine place to dispose of plutonium. It would melt,
spread out, and harm no one or no thing.

  But like I said before, the problem is how to get it there. No launch system
today is more reliable than 95% and if you wanted to dispose of an entire
reactor that would surpass any and all launch capacity.

  I'm not great at these numbers, but let's consider the Saturn V and how much
"stuff" it could get into the sun. As I recall, the Saturn V put sever hundred
thousand pounds in low earth orbit but only 70,000 pounds in lunar transfer.
I don't know for sure, but I'm sure that you would need at least 90% of that
weight as fuel to get into an eliptical orbit with a high point near earth
orbit and a low point within Mercury's orbit.
  
  Of course you could play the pinball game using planets to change the orbit
which works great for getting one small probe somewhere but would be an enormus
control problem for tons of radioactive trash. 

  So perhaps a Saturn V could get 7000 pounds in an orbit that came close
enough to the sun to melt it. As for entering the sun, that would probably
take more. Anyone feel free to correct my numbers but I'm sure that you
would never cost justify disposal of 2 to 5 tons by use of a Saturn V class
launcher. That would be far too expensive for each trip and wouldn't scratch
the surface of the problem.

  George

    Yes,  Let's alter the nuclear composition of the sun by dumping
    all the garbage we can into it... if it truly could be dumped 'into'
    the sun.  I could be the premise of a good science fiction novel.
    You know, how we subtly altered the sun's composition and caused
    the fusion reaction that has powered it for these billions of years,
    to go out.  Remote but scary possiblity, isn't it?  Just a thought for
    Halloween ;').

	Re: .8

	Huh?  Take a look at the relative sizes of the earth and the sun and
you'd see that we could drop the *entire* earth into the sun without really
altering its overall makeup one bit.


	Re: .0

	Dropping the waste into the sun *is* a very energy-expensive
proposition, even if it was sling-shotted there via Jupiter.  Why hit the sun,
however?  If we really wanted to get rid of the waste and not recycle it, you
could just aim it on an orbit that will take it right out of the solar system.
It takes less energy per kilogram to to leave the solar system than it does to
get the waste to the sun.  (Unless you're talking about putting them up in solar
orbit with solar sails to *slowly* slow it down and drop it into the sun.  That
is relatively inexpensive, but it takes a *long* time to get the waste disposed
of.)

	Re: in general

	I agree with the notion that recycling makes a lot more sense than
does blasting the "wastes" into some non-earth location.  Even the plutonium
could be recycled if we really wanted to.  Put it into a neutron howitzer to
change its isotope from a long-lived one into a shorter-lived one (the further
outside the stable-zone (if there is one for that element) the isotope number
is, the shorter its half-time typically becomes).  We don't have to live with
the stuff for hundreds of thousands of years.

								-craig

    	See also Topic 453 for discussion related to space pollution.
    

  RE: Getting hazardous stuff into space reliably

  With the assumption that a rail-gun style of launcher would have many controls
to it, I've got to believe that a rail-gun would be the way to go.  This would
merely be a way of getting the material out of the atmosphere and up to some
sort of a tug.  The tug (a big engine) would then move the hazardous material
out of orbit, brake, and drop into the Sun.

  When I said 'controls' above, I meant that if anything seemed to be going
wrong with the launcher, it should be possible to apply braking force or
something along those lines to slow the package down, let it drop and be
recovered.

  More parameters/assumptions:

  1. The line of fire is over water for (arbitrary number) 500 miles.

  2. The 'vehicle' that was being launched would be merely a ballistic case with
a radio transponder for tracking purposes.  The simplicity of the cases and the
need for one-time use and the large number of the things sounds like a way to
really understand their construction/manufacture and reliability.

     The cases would really be ballistic.  From the muzzle of the launcher to
orbital insertion would be a committed phase.  A period where the laws of
physics are relied upon to do their thing.  Note: I don't know if it's possible
to do an orbital insertion with a one-time energy expenditure from the surface
of the earth.

  3. Any given failure of the launcher would impact a very small set of cases.
This is as opposed to a Titan launch with 10,000 pounds of plutonium stored on-
board.  If that blows up on the pad, you might have your hands full.

  A problem with this setup is the problem of retrieving cases which have not
been given sufficient energy from the launcher.  They could fall into the water
and sink, or drop inland somewhere, perhaps hitting a building at a non-trivial
speed.  The cases could be designed to float (will Shuttle tiles float? I recall
them being very low density) for the former, and the latter shouldn't happen
assuming that the low-energy from the launcher would be expended while
travelling through the higher density layers of the atmosphere.

  Given another control of the launcher, an energy monitor (undoubtedly
necessary to the operation of such a beast), the path of the case could be
predicted with some accuracy while the radio transponder would allow for
active tracking.

  The down-side.  I can see the media dealing with the first case that lands in
some guy's back yard, producing a smoking hole 8 feet deep and 12 feet across.
This should be extremely rare given that there should be a large downrange safe
area (over water) into which the cases could be braked by the launcher when it
detected a problem (of course, the problem could prohibit braking).  Perhaps a
braking mechanism could be built into each case... Of course, now we're looking
at a more complex vehicle.

  It'd be interesting if the rail gun required so much power that it spent all
its time launching radioactive waste from its own nuclear power plant...

  Hey, we could require every nuclear power plant to have a rail launcher!
Yeah, yeah, that's the ticket!  :)

  Having fun playing with ideas,

John

    Re: .9
    
    If you'll take note, I said a subtle alteration.  Dropping the entire
    Earth into the sun would be a little drastic.  Are you sure that you
    really want to solve the problem that way :') ?  I still think that it
    would make an interesting premise for a book, although.

    Putting things into the Sun is just not very difficult its
    very very very very very very very very very very difficult.
    
    If I remember correctly a craft would need a velocity change
    in the order of 200 Km/s (Low Earth Orbit is only 7.9 Km/s).
    Using good old Hydrogen-Oxygen rockets, that means that the
                                       18
    fuel mass must me around    55 * 10   times the payload+craft 
    mass. Much easier to send it out of the solar system or of
    using another solar system body to dump the waste. 
    
    For example our Moon. The main reason that radioactive/toxic 
    materials are so bad on Earth is that Earth is geologicaly
    active, that it has an atmosphere, a water cycle, etc. On the
    Moon even if there were people living there, the wastes would
    not be a problem, they would just sit there and contaminate
    nothing. All people would have to do would be avoid the area
    a few hundred meters around the dump.
    
    Of course, even if space transportation costs and risks were
    lowered. People may choose other non-space ways. Putting the
    stuff in a very deep hole and forgeting about it, in the deep
    ocean, or sending it into the Earth's center.
    
    Regards,	Gil

RE:           <<< Note 657.13 by 52331::ANDRADE "The sentinel (.)(.)" >>>
    
>    On the Moon even if there were people living there, the wastes would
>    not be a problem, they would just sit there and contaminate
>    nothing. All people would have to do would be avoid the area
>    a few hundred meters around the dump.

Sounds like the Love Canal to me.  What's the real difference between a few
hundred meters and a few kilometers?  I'd say no difference.  So if it's bad
on Earth, it's bad on the Moon.
    
>    [On Earth] Putting the
>    stuff in a very deep hole and forgeting about it, in the deep
>    ocean

This is what people have been doing for decades (depending on your definition
of a deep hole).  Do you think it's worked?  I don't.
						-- Tom

We're starting to drift from a Space topic here, but I assume that .13's
definition of a deep hole is "a really deep hole".

One of the ideas I've heard bounced around for nuclear waste disposal is to
bury the stuff at the side of a subduction zone (I think that's what they
are called).  This is a spot on the earth's crust where one land mass is
being forced downward toward the mantle.   While it may take thousands of
years for the waste to actually move down that far, once it did it would
not likely come back again for millions of years.

I believe the idea that should be given the widest view is that there is
no rabbit to pull out of our hats to get rid of our most toxic wastes.  There
are risks and very high costs associated with all forms of disposal and
people had better start resigning themselves to that fact for our historical
generation of wastes, and continue to find ways of eliminating the need to
generate them tomorrow.


- dave

	Re: .12  Dropping the earth into the sun

	Well, its going to happen anyway.  In a few billion years the sun will
turn into a red-giant and its outer edge will be (roughly) out to where Mars's
orbit is.  All of us "inner planets" will be absorbed.  But no, I wouldn't
advocate "going solar" in this way early... ;-)

	Besides, "drastic" is from the earth's perspective.  I was trying to
point out that it will not be a "drastic alteration" from the sun's perspective
when it picks up this speck of dust that has been floating around called earth.


	Re: .11

>physics are relied upon to do their thing.  Note: I don't know if it's possible
>to do an orbital insertion with a one-time energy expenditure from the surface
>of the earth.

	If you're using the phrase "orbital insertion" to mean placing the tug
into a fully orbital (ie. it goes round and round and round the earth to its
heart's content) path, the answer is No, physics doesn't allow that.  If you're
just taking about getting it several hundred miles up so that, presumably,
something else can "catch" it, that's possible.  (ie. in the act of catching
the tug, energy has been given to the tug by the "catcher" to adjust its
orbit to a fully orbital one.)

							-craig

.0's idea has always intrigued me, but I'm not sure how (or if) it's possible.
I do agree that more thought, energy and effort should go into recycling here on
Earth.

The idea of sending cargo vessels of nuclear waste (or any type of waste, for
that matter) on a trajectory out of the solar system is, IMHO, bad.  Unless, of
course, we're interested in providing some targets for the Klingons to shoot at
(but that's another story, and notesfile). :-)

Now it's time to ask the stupid (read: novice) questions.  Why are we so
concerned about a controlled approach to the sun?  Would not a vehicle, launched
on some trajectory toward the sun, eventually get "hooked" by the sun's gravity
and get sucked in?  Isn't there a point at which the Earth's gravity (or any
other planet's gravity) loses the tug of war with the sun?  If so, is that point
so far away that it's too expensive (or impractical) to send a load of waste
there?  Am I out in space here (pun intended :-))?

And to further add fuel to the fire (pseudo-pun intended here), if a program of
launching nuclear waste into space was initiated, how do you think these
anti-nuke groups would react?  I mean sheesh, they go off the deep end now when
we attempt to launch a probe with a teenie-tiny RTG, imagine the lip service
we'd have to put up with when the announcement comes: "NASA to launch 100,000
pounds of nuclear waste toward the sun."  Ya right!

...Roger...

>Now it's time to ask the stupid (read: novice) questions.  Why are we so
>concerned about a controlled approach to the sun?  Would not a vehicle, launched
>on some trajectory toward the sun, eventually get "hooked" by the sun's gravity
>and get sucked in?  

  The answer to this, for all practical purposes is no. It has to do with the
way orbits work. As of now, all toxic materials, along with everything else
on Earth (in fact earth itself) are "hooked" by the sun and are in orbit around
the sun. Putting the math aside, the way an orbit works is that things in orbit
are always "falling" toward the thing they orbit but because they have a
volocity to the side, they keep missing the object.

  Things in low earth orbit suffer orbit decay because they are really in the
upper atmosphere and drag gradually slows them down so at some point they
no longer miss the earth's lower atmosphere. The sun's "upper atmosphere" would
probably slow things down but not for several billion years. If it did slow
things down quicker, Earth would have fallen into the sun billions of years
ago. 

  When they talk about how a space craft "leaves" the influence of earth
gravaty and "enters" lunar or solar gravaty, what they really mean is that the
gravaty of one body becomes greater than the other at the cross over point. All
particals in the universe are constantly being pulled on by the Earth, Moon,
and Sun to some extent as they are each pulled on by every partical in the
Universe. 

  The bottom line here is that no natural force would cause the orbit of the
trash to decay to the point where it would enter the sun. It would take tons of
fuel to get each pound of material into the sun. If you were going to dispose
of stuff in space it would be far more economical, once you got it up there, to
fly it behind Jupiter and sling shot it out of the solar system. It would take
40,000 years just to reach the Ort(sp?) cloud and by then it would probably not
be radioactive any longer anyway. 

  Space is a big place. If the entire planet Earth were busted up into pieces
and shot out of the solar system it would be so small compared to the space
that no one would notice it's presence unless they went looking for it.

  George

    Re:.17 & others
    
    	OK, I've heard enough. Class, it's time for a little lesson in
    celestial mechanics. Let's assume that we have a spacecraft in a low
    Earth orbit. This spacecraft lights up its rockets so that it escapes
    Earth in the opposite direction in which the Earth orbits the Sun. Once
    it left the Earth's sphere of influence, this spacecraft would orbit
    the Sun as an independent body.
    	Let's see what effect various additions of velocity would have on
    this Earth orbiting spacecraft: If this spacecraft increased its
    velocity by about 4 km/s (typical of a spacecraft heading to Venus) it
    would end up in a solar orbit with a perihelion distance (i.e. closest
    distance from the Sun) of about 0.616 AU (about 92.1 million km). If
    this spacecraft increased its velocity by 10 km/s (typical of a
    spacecraft heading to Jupiter, if it were aimed in the right direction)
    the spacecraft would enter a solar orbit with a perihelion of 0.167 AU
    (about 24.9 million km). In order for this spacecraft to have a solar
    orbit that just touches the Sun's photosphere (what we would call the
    Sun's "surface"), this spacecraft would have to increase its velocity
    by 24.5 km/s (much faster than ANY spacecraft launched to date).
    	Now for lesson number two: let's assume we have a nuclear powered
    rocket stage with an Isp of around 1000 (Isp is a measure of how much
    thrust one gets out of a pound of fuel). This is twice as good as the
    best rocket stages in use today. Let's assume further that this stage
    weighs 15 times more fueled than it does empty (which is damn good by
    today's standard's). With this being the case, this nuclear powered
    rocket stage could only send a payload of 1.5% of its original mass. In
    other words, say we used a Shuttle-C to orbit this stage and it payload
    (which for the topic under discussion is nuclear or some other sort of
    hazardous waste) and it has an in orbit mass of 100,000 pounds (the
    capability of the Shuttle-C). This stage could only send 1,500 pounds
    of payload (waste PLUS its container) on a destructive rendevous with
    the Sun. All in all it is NOT very effiecient.
    	If you are really bent on sending this waste somewhere into space,
    send it to the Moon. Using this same sort of nuclear powered upper
    stage with a 100,000 pound in orbit limit, one could send 49,000 pounds
    of waste to a soft landing on the Moons surface. Its a lot more
    economical no matter what sort of propulsion technology you are using.
    
    				Drew
    

  Good description Drew, but I still think deep space would be a better
place than the Moon. We may want to use that some time within the next
20,000 years and while I believe the people that say toxic waste is not
as dangerous on the moon, we don't know who will be digging where 7,000
years from now.

  So if a Shuttle C could send 49,000 lb to a soft landing on the moon,
how much could it send on a flyby behind Jupiter such that it would leave
the solar system?

  George

    
    
    About 15 years ago, Isaac Asimov proposed putting radioactive
    trash into Lagrange points.  After explaining Lagrange points
    and listing the advantages of this approach, he then switched 
    gears in his essay and pointed out that historically most of
    the planets and moons have been named after figures in Greek 
    mythology.  Therefore, he suggested that this zone filled with 
    deadly trash be called "the Trojan hearse".
    
    I'm sure the only reason he wrote the essay was to inflict the
    pun.  But it's not a bad idea on its other merits.
    
    Charlie
    

I have truly enjoyed reading the information on how we could
actually send enormous loads of things to the Sun.

A couple of misconceptions I need to have clarified:

1. One of the original satalites that was sent up by the US or USSR 
didn't make it into orbit and I seem to recall that it drifted to the
Sun. That is why I thought a Solar orbit is something of a graveyard.

2. Did it take a huge lifting capability to send the Voyager probes
to the outer planets.

3. It was an odd thing physics-wise that it would be easier to just
send the stuff into deep-space rather than sending to the sun.

I find these concepts facinating, thanks for the information.

Fred Mudgett

CAUTION:
NON-SPACE RELATED CHESTNUT TO FOLLOW,

 
This morning our significantly above average 7 month old got up at 04:00 and 
while my wife was feeding him I chose that opportunity to share with her all
this I have learned about orbital science and how we  could concievably use it
to get rid of nuclear waste. (I did this  of course because I'm a caring 80's
guy!) She eventually stopped me mid-sharing and asked what the BLEEP I was
talking about and that she didn't care even if I did explain it better. I asked
her what  she did care about and she said The Patty Duke Show. So I asked 
several PD questions including:

1. What was the father's name? Martin
2. What was his twin brother's name? Cousin Herbert
3. What did this cousin do for a living? a reporter
4. Why did Cousin Herbert desert his daughter Cathy, or was it Patty
you know, the one who adores a Minuet? Go to sleep Fred or I'll kill you!

So much for sharing I'm going back to my ole self.

Fred Mudgett

    
    
    	This discussion has prompted quite a variety of responses!
    	The concept is great at first glance. shoot it all into a furnace
    	and let it burn to ashes. 
    
    	If you ask your sons and daughters,' where do computers come from?'
    	and one or both of them replies, " the Sun Daddy, that's where
    	everything comes from", you've been duly and unequivocably answered
    	correctly. This answer will do for the origination of just about 
    	everything. 
    
    	We are not capable of surviving without it [yet or for some time to
    come] Nothing on this earth is capable of surviving without it. 
    
    	I believe it was in the early sixties when this method of disposal
    	first came to issue. This idea was quickly and Permanently put to
    	rest by every nation involved in an international Science group.
    	I can't recall the name but it is to Science what the Geneva
   	Convention is to War and Politics. It may be the International
    	Science Foundation but I am guessing. 
    
    	Their thinking was, as one noter in this topic implied, ANY
	alterations to our precious Sun were unthinkable as the
	repercussions no matter how small could spell the end of the human
    	race. If we managed to put it out- God Forbid - because of some
    	alteration in the Fusion mechanism which we don't understand yet,
    	we'd all have about Ten minutes to think about it as we freeze 
    	solid for eternity.
    	
    	So even if we did have the technology to blast the waste off
	cheaply,safely and efficiently it wouldn't be conducive to our
    	survival.
    
    	It would probably be easier to find a way to cease radioactive
    	decay in materials than just dump it.
    
    	Regards,
    
    	Michael L'Esperance
    

Re:.22
	I'll give these questions a shot:

>1. One of the original satalites that was sent up by the US or USSR 
>didn't make it into orbit and I seem to recall that it drifted to the
>Sun. That is why I thought a Solar orbit is something of a graveyard.

	No, solar orbit isn't any sort of graveyard. The incidences you
are thinking about include the Soviet's Luna 1 and America's Pioneer 4 (among
other space probes). There is nothing magical here at all: These probes
were launched just a bit above or very close to Earth's escape velocity
when they were sent to the Moon. After they passed the Moon they were 
travelling fast enough to escape Earth's influence. Once they did that,
these probes entered solar orbits similar to Earth's orbit around the Sun.

>2. Did it take a huge lifting capability to send the Voyager probes
>to the outer planets.

	When the Voyagers were launched they used the MOST powerful launch
vehicle then available in the West: the Titan IIIE/Centaur. This booster could
send over 15 tons into low Earth orbit or 3.5+ tons to the planets Mars
or Venus. The flight to the outer solar system required so much energy 
that even with an additional "kick stage", this rocket could only send a
1,800 pound payload out on Voyager's mission. 

>3. It was an odd thing physics-wise that it would be easier to just
>send the stuff into deep-space rather than sending to the sun.

	After playing with mechanics for over a decade and with a B.S.
in Physics, this stuff is not so odd to me at all now :-)

	Oh and just one more thing about this discussion: I don't advocate
sending any sort of wastes to the Sun, the Moon, Jupiter, deep space or
any other place. I made my position on this subject clear in a previous
note. The purpose of this last note Re: celestial mechanics was to dispell
all the misconceptions about celestial mechanics that some of the noters
had.

				Drew

I've seen one other misconception here a couple of times.

Even if the reactions powering the Sun were to turn off completely today, we
wouldn't know about it for many thousands of years (forgot the exact number). It
takes a long time for energy to work it's way up from the core of something that
big.           -Tom R.

    Yes,  I've heard the same theories.  Does the speed of light or other
    electromagnetic energy figure into this?  That is, the energy emitted 
    from the fusion reaction travels out as combination of things, photons,
    various forms of radiation, neutrinos, and others.  I would expect that
    the photons that should travel at ~186,000 mps and would pass rather 
    quickly out of the sun, unless there is something I'm missing (like 
    the enormous mass of the sun).  Is there is some resistance generated, 
    inhibiting a photon that is released from the center of the reaction from 
    passing to the photosphere and beyond?  I don't believe that I've seen
    any theories on holding photons in stasis anywhere(?).  Could anyone
    explain the process in more detail?
    
                                 

    Re:.26
    	The neutrinos, which react VERY weakly with matter, pass unimpeded
    from the core of the Sun at the speed of light. The photons on the
    other hand, which DO interact easily with matter, basicly get scattered
    around by the particles (protons, free electrons, etc.) in the Sun at
    random. It then takes thousands of years before these high energy gamma
    rays slowly migrate to the surface of the Sun, losing energy all the
    time, until they finally emerge unimpeded as (primarily) photons of
    visible light.
    
    				Drew
     

	Well, if we did manage to turn off the sun's fusion in the middle, I
think we would know it sooner than than the thousands of years that it currently
takes for the energy to migrate to the surface.  The sun is a big ball of gas
and its "diameter" is a very delicate balance between the energy pressures
on the inside pushing outward and gravity trying to smush the whole thing down
to a neutron star.  If the internal reactions were to suddenly go "out", we
should see it long before thousands of years have gone by due to the diameter
of the sun starting to contract.  (And yes, there are astronomers who watch the
sun in incredible detail.  I've seen figures citing hundredth's of one percent
differences detected in the energy output from the sun, so they should be able
to see something as obvious as even a slight contraction.)

	If you really want to ponder something odd -- when the sun goes to a
Red Giant status, it is "red" because the surface is cooler than it is now.  But
it requires a greater core energy output to expand the gas diameter.  Therefore,
changes in the surface temperature are often opposite of the changes happening
in the core.  (ie. the surface gets cooler as the core gets hotter)

								-craig

    Re:.27
         I take it then, that the effective resistance of so many particles in 
    the way causes the photons to diffuse more slowly out of the sun?  Sort of
    like as in Brownian motion?   Writing about this reminds me of the science
    fiction stories about a material called 'slow glass' that delayed viewing 
    of light transmitted through it by years.   
    
         I would assume the first thing we would notice would be solar 
    neutrinos (which I understand are not being discovered in the predicted 
    amounts anyway) drop to almost, if not zero in our detectors.  Would
    this seem correct? 
                  

This is a very interesting discussion.  However, wheither it will
take 10 minutes, or thousands of years, or millions of billions
of years for the sun to go out if we goofed with its internal
mechanism seems irrelvant to me.  If we cause the sun to even
flicker in the slightest we're fooling with the only sun we've
got, and if its our generation or one an infinite number of
fathers from now, its still us goofing with somebody else's life,
and I don't like that.

By the same token, I'd hate to think that one of the few legacies
we leave to the universe is a rocket full of nuclear waste,
though maybe someone somewhere has a great use for it!

Of the ideas I've heard so far I like the idea of storing it on
the moon where we can get back to it if we ever find a good use
for it, or perhaps sending it to a forever desolate and
uninhabitable planet, like Venus.

By the way, just how much waste are we talking about -- I mean,
what would the waste of a typical power station or nuclear sub
weigh?  Bet a lot of the weight is in the container -- could we
ship it to the launch site in a container, then have robot arms
load it into the rocket, then we could scram out of the way and
let it go, except for the anti-nuke protestors clinging to the
tail cone, of course.

  I'm against the idea of disposing stuff in the sun right now due to the
orbital mechanical problems just mentioned so please don't interpret this as a
vote that it is feasable with today's launch capacity. 

  However, I don't agree at all with the contention that we could cause a
"flicker" in the sun if we deposited all of our nuclear waste there. 

  Basically, if you are talking about pushing the stuff around in space with
earth based launchers, the weight of our nuclear trash is tremendous. However,
if you are talking about it entering a star, like the sun, it is so small that
it is practicaly non existent. I don't believe that there would be any noticable
change in the performance of the sun what so ever even if a small asteroid
entered the sun. Sure, astronomers might be able to measure something but
I doubt that we'd need to put an extra sweater on the following winter.

  What ever earth based material approached a sun class star would melt
and chemically decompose long before they got anywhere near the surface.

  George

RE: The Moon or Venus or any other place.

I'd rather not put the junk in any other "back yard."  We (humans) made the
junk; leave it in our back yard (the Earth).  That way if we trip over it often
enough we might make up our minds to solve the real problem (the generation of
junk).  If we sweep it away, there probably will be no impetus to ever deal
with the real problem.
						-- Tom

    	We may be able to terraform Venus someday for colonization, so
    I don't think our descendants would appreciate our garbage on their
    new world.  The same goes for the rest of the solar system, excluding
    the Jovian planets - but they shouldn't be turned into trash cans,
    either.
           
        I for one would like to see some concrete evidence one way or
    the other as to whether dumping nuclear waste into the Sun would
    actually have any effect on our star, rather than just emotional
    guesses.
    
    	Larry
    

From what I've seen here, it's pretty clear that it will be far, far cheaper to
recycle the waste or even prevent the initial generation in the first place.
This is even considering the nature of muclear waste.  The money it would take
might well exceed the amount needed to get cold fusion working, if you catch my
drift.

Wook

    I don't believe that there are people out there that think,
    that by dropping a few tons or a few Million tons of nuclear 
    wastes in the Sun. Could change it in any way at all.
    
    Our Sun is a STAR, its big BIG, and it wouldn't make more then
    a local and temporary change if you droped all the planets and
    the asteroids into it. 
    
    As for altering its composition, you must remember that the planets 
    are just little bits of the cloud that condensed to form our star.
    Inside the Sun you will find the same things that exist outside of it.
    
    Gil

    Re. .35:
    
    I think you are missing the point of the objections to dropping our
    nuclear (ie. radioactive) waste into the Sun.
    
    Although the stuff would break apart CHEMICALLY, it is the properties
    of the nuclear material which would have an effect, if any.
    
    It is true that, as far as we know, it would take a very long time for
    the material to get to the core of the Sun, where the thermonuclear
    reactions occur, and that the amount of material involved is tiny in
    comparison to the Suns mass (which is around 2x10^30 kilogrammes).
    
    But are we prepared to bet the future of the Earth that we are right?
    There is already good reason to question our understanding of the
    processes which power the Sun, because of the well-known "missing
    solar neutrino" problem. This one observed discrepancy between theory
    and observation suggests that we do not understand stellar physics as
    well as we would like to think we do.
    
    If an asteroid drops into the Sun and puts it out, that is an event
    over which we have no control. But if we were to do something which
    resulted in the Sun going out, the results would be down to our own
    irresponsibility, and this time we would not have a second chance to
    put things right.
    
    The old addage "look before you leap" is still relevant in the modern
    world, but is unfortunately ignored by people who want to try
    spectacular solutions to problems.
    
    
    Dave Hazel

    Re. .35
    
    If you'll note, I believe that nothing much would happen if the Earth would
    drop into the Sun at this minute.  That is, except for the abrupt halt of 
    this conversation.  
    
    How about this little subtlety...Everything that we propose to ship off 
    Earth's surface to whatever space junkyard we choose will be at the cost 
    of Earth's total mass.  I admit that we would have to jettison an enormous 
    quanitity of material to make it visible, but ever so slightly, Earth's 
    gravity decreases (assuming that one could ship out enough mass to more
    than compensate for the meteors, dust, and whatever we normally collect
    over time due to our attraction).  Hmmm... another possible story of
    how we affected the position of our planet due to altering local
    gravity and the balance between the forces that hold the solar system
    together.  Isn't fantasy interesting?   
    
    Overall, the whole subject of exporting our waste materials to other 
    bodies is pretty senseless.  It would be much too expensive for the
    mass that we would need to move.... It already costs billions to send
    the limited material that we (mostly) temporarily export.  It would be
    much better to not generate or find solutions for the wastes, here.
    I move that we keep our local space, and the bodies therein, unlittered 
    for the future when we may really need them.  I'm not talking about a 
    couple of hundred years here, but thousands to tens of thousands of years 
    or more.  
                                       

    Re. 36, 37
    
    For the record, I am against sending anything into the Sun.  Not 
    because it would do any harm now or in a billion years.  It wouldn't.
    But because it isn't economical. 
    (We know enough about the Sun, to be sure of this.)
    
    If we choose to send wastes into space then the Moon is the obvious
    place to put them. That not is to say that we should, even the Moon
    is expensive. And the Earth Launch risks would have to be proven to
    be less then the Earth disposal alternatives, overall.
    
    Personally, I hope that by the time such a thing would be feasable. 
    It will not be needed because Fusion Cold and Hot will be here.
    
    Gil

    	I should have said this sooner:  I believe there is a United
    Nations treaty forbidding the disposal of nuclear waste on the Moon
    and any other solid body in space.  I do not believe that the Sun
    was included in this law.
    
    	Larry
    

    Re: Our waste upsetting the Sun 
    
    	It is absolutely amazing the misconceptions people have. OK people,
    it's time for a class in the abundance of elements in the Sun. The Sun
    contains about one part in 3X10^12 uranium (which we'll assume for the
    moment is the predominant elemental component in nuclear waste). Since
    the Sun has a mass of 1.991X10^30 Kg, a little math will show you that
    the total amount of uranium in the Sun amounts to 6.7X10^17 Kg. Now,
    I'm not too sure how much nuclear waste there is in the world but I'm
    sure that a worst case estimate is that there is a million metric tons
    of the stuff around (that is REALLY worst case!). 
    	Assuming for the moment that we had the technology to send all this
    waste to the Sun, this waste would amount to no more than a one part in
    6.7X10^8 increase in the Sun's total abundance of uranium. Scientist have 
    a word for this kind of increase: It's called "insignificant"! There
    would be NO change in the Sun from this kind of input of nuclear waste.
    	Now I know the next question: "But nuclear waste is not composed
    soley of uranium". True. I was doing a worst case senerio. Typical
    nuclear waste contains significant quantities of iodine, strontium,
    radium, lead, and other elements. But all these elements are hundreds
    to as much as hundreds of thousands times more plentiful in the Sun
    than uranium making the impact on the Sun's composition all the more
    insignificant.
    
    	Now, as I have said before, I do NOT advocate sending our wastes to
    the Sun, Moon, Venus, or any place else. If the stuff is so bad we
    can't live with it, DON'T PRODUCE IT TO BEGIN WITH!
    
    				Drew
    

To me, how much it costs to send trash off the Earth is totally irrelevant.
Even if it were free; even if we could just close our eyes, click our heels
together three times, and wish the trash off the Earth, we shouldn't do it.

I also dislike the reason of not wanting to put trash on some other planetary
body because humanity might "need" that body later.  I don't think of the
planets etc. as more territory for humans to consume.
						-- Tom

    	Earth is not going to last forever, certainly not the way we
    are already treating it.  Colonizing other planets and moons will
    be a reality some day.
    
    	It does *not* also automatically mean that we will be trashing
    these worlds as well.  No other world, including Mars, allows a
    human being to just take a stroll outside without considerable
    protection.  Survival and cooperation will be the key words for
    those colonies, as without them they will surely die.
    
    	Unless the human race goes back to living like the Amerinds once
    did, we will have to explore, live on, and use other planets eventually.
    We will also be doing our Earth a favor in the process.
    
        Larry
    

	Re: .40

	Continuing the notion of "insignificance"...  Most people acknowledge
that arsenic is a poison.  Do you realize that you have arsenic in your body
*right now*?  Why aren't you dead?  That's right, its in such insignificant
quantities that it is virtually non-existant.  The *entire* earth, when compared
to the sun, is but a speck of dust floating about in space.  The total amount
of nuclear waste is an incredibly minor speck of dust even when compared to
*only* the earth's volume.  Therefore, the waste in the sun would only a minor
speck off a small speck -- ie. its as close to "nothing" as you can effectivly
get before you hit an actual honest-to-goodness zero, zip, nada.  And, as .40
pointed out, this "waste" isn't exactly introducing new elements into the sun.

	Now, having said that, I'm still not in favor of dumping the waste into
the sun due to the lousy economics of it and the chance that we can reuse the
stuff.  But put out the sun with this waste?  You're right, it could make a good
fiction book and that's about it.

								-craig

    Re. .41
    
    Sorry, I'm one of those people who would like to see us colonize the
    universe and in order to do that, we will have to colonize/exploit the
    solar system and move out from there.  Assuming we have the will to
    survive as a species, our first step will be to move outward from the
    home world, provided a lot of technical and people issues are solved. 
    
    Moving outward from this planet will be a worldwide goal because of the
    resources required to mount and intially to sustain, expansion.  I
    imagine that this will happen as we begin to exhaust planetary
    potential (we're not there yet).  For those of you who believe that
    this could never happen, if you remember, the first colonists who came 
    to the America's were fond of remarking who limitless the resources were 
    ('trees enough to last forever').  Conservation would slow down, but
    not eventually stop the eventual consumption of the planet since we
    will be soon passing the threshold of human population that this world
    can support. 
    
    Hopefully, we don't lose the WILL to survive as a species in the
    meantime.  A lot of other things could wipe us out. There are a lot more 
    reasons for moving outwards.  For those who wait for us to become a world 
    with all our social ills wiped out and then concentrate on moving out, 
    the status quo is an easy thing to rest forever on.  Colonizing other
    worlds should be a goal for the human race to focus on collectively. 
    We still have a lot to work on in this vein.
    
    I also don't believe that we will move out among the stars next week.... 
    but we WILL go at some time in the future.  If only for the survial
    aspect of it. 

RE: .42 and .44

I didn't advocate that humans stay on Earth forever.  I said that I don't think
we should view the rest of the universe as an exclusively-human playground to
be dealt with any way we see fit.  It's the "humano-centric" stance that
bothers me.  There are other things worthy of respect and consideration.
						-- Tom

    This whole conversation is bothersome from several aspects, but the
    current scope of this note misses the dynamics of our environmental 
    situation.  Hazardous waste awareness is a recent development as are 
    the problems to humanity caused by keeping the material in a dynamic
    environment.  Earth bound storage solutions to the problem do not fit
    the earths geologicial time scale, nor do these solutions fit the need
    for protection for humanity from the materials.  Methods of "recycling"
    do not come risk free as maybe indicated.  Dynamics for the atmosphere,
    oceans and crust all bring focus to the difficult nature of rendering
    these materials "safe".   It has been less than a century for humankind
    to discover the limits and risks of using this dynamic environment for
    mankinds "dump".  The questions of the future of such practices are
    just being explored.  
    
    Of a more pressing concern is going to be food production during the
    next several decades, and not food packaging.  As humankind enters the
    breakeven population this limited earth can support, what has been done
    with scarce land resources for the production of required food will be
    the near term concern.  If "wasted lands" can be cleansed to free up
    and relieve the stress on the food chain, and a technical solution to
    the problem exists, then the disscussion within this note may be
    geramin to the future of the Earth and its home to humankind.  However
    if we focus on the concerns of feeding the very near future generations
    at the current levels of population growth, this Earth appears very
    finite in its current capability.  (Just as an asside toss in food
    supply uncertainties in light of global warming!)
    
    It maywell be a mote point to worry about the technological
    requirements of waste disposal, when there is not sufficient technical
    investment in maintaining the current thread of life.
    
    Les
    
    

RE:        <<< Note 657.46 by 37292::MOPPS "SUCCESS = GOODNESS - ERROR" >>>

I don't recall anyone postulating that waste handling was the number one
problem facing mankind.

If the issue of food production were to be discussed (in another notes
conference), then I sumbit that the issue of limiting population growth should
be addressed, rather than trying to find ways to accomodate a perpetual growth
in population.
						-- Tom

    Sorry to get off the base tract.  The issue of disposal of "nasty
    wastes" got my thought processes thinking of causes of the wastes in
    the first place.  One of the more touted limiting factors to the growth of
    atomic energy has always been the disposal of waste.  (And of course 
    safety of operations, the other.)  It is of little value to consider
    the disposal problem without viewing the reason there is a problem and
    wether the problem is dynamic, (IE:  going to continue because of use
    of the technology.) OR static (IE:  All the waste produced by weapons
    and energy by-products.  It is "unsafe", therefore some other energy and 
    weapons technology will replace atomic technology.)  I would support
    lunar temporary disposal for a short term solution for the both the
    static and dynamic waste disposal problem.  I would view the need to
    find an even longer term solution to the problem if the situation were
    viewed as dynamic.  Perhapse the sun shot or perhase extra solarsystem
    solutions.  I view the current short term need for waste storage or 
    disposal on Earth non viable because of the long term hazard posed by
    the waste.  I also view using the lunar or smallar storage asteroid as
    viable given the current understanding for the Suns dynamics, volume of
    material to be processed, and "fit" of current technology with the
    economics.  Finding; a safe, reliable, cost effective, extra-terrestial
    storage location and technology, represents sufficient challenge without
    having to dive into the unknowns of shooting the stuff to the Sun.  And if
    there is a solutuion on the horizon (within the next 20 years) using a
    "safe" space approach, then maybe the problem of "safe energy", food,
    economic development, life style, global warming can be found within
    the same time frame.  If not, then of a larger concern will remain
    global warming, and the impact of this avoidable problem to the food
    chain.  
    
    Les
    

*        <<< Note 657.48 by 37292::MOPPS "SUCCESS = GOODNESS - ERROR" >>>
*                          -< The next twenty years? >-
*    economics.  Finding; a safe, reliable, cost effective, extra-terrestial
*    storage location and technology, represents sufficient challenge without
*    having to dive into the unknowns of shooting the stuff to the Sun.  And if
*    there is a solutuion on the horizon (within the next 20 years) using a

Concerning Nuclear waste disposal:

I attended a conference on Aneutronic fusion in Washington, D.C. in April '89.
Glen Seaborg opened the conference and one of the contributors was from China.
The individual from China had done work which was all theoretical but summed up
was:  Perhaps we could create 'strange matter' (out of quarks) and if we could
in some configurations this piece of 'strange matter' could grow by absorbing 
nuclear waste - eliminating the radioactivity because the matter would be 
transformed into 'strange matter' and no longer cause a problem.  The 
presentation was both 'strange' and 'futures' but points out there may be 
solutions other than what have been presented so far that we can't even dream 
of at this time.

Article: 2208
From: [email protected] (Henry Spencer)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: Sun, 12 Jun 1994 22:20:43 GMT
Organization: U of Toronto Zoology
 
In article <[email protected]> [email protected] (Clayyy) writes:
>Will it ever be possible to send nuclear waste to the sun...
 
Possible, but probably not worth the trouble.  Launching it to solar-system
escape velocity is considerably easier.  To get it into the Sun, you must
kill nearly all of our orbital velocity, 30 km/s.  Getting it to escape
needs only about 12 km/s.  (Both of these are over and above Earth escape,
of course.)
 
Launch to solar-system escape can be done with something like a laser
launcher, which has a lot of advantages (for one thing, you can afford
to launch thousands of test payloads before you start on the real stuff,
so you can qualify the launch system to any required reliability level).
Jordin Kare looked into this at some length a while back; as I recall,
his conclusions were:
 
- It's more expensive than putting it into a hole in the ground.
 
- It's less expensive than putting it into a DOE-designed hole in the ground.
 
- The US is not going to do it, because there is too much political capital
	invested in DOE-designed holes in the ground already.
 
There is also the question of whether we might someday want to recover the
waste, since there are useful materials in it (although it is currently
too expensive, in dollars and in political impact, to extract them).  If
you really must get them off Earth, soft-landing them in a small area on
the lunar farside is probably better.
-- 
"...the Russians are coming, and the    | Henry Spencer @ U of Toronto Zoology
launch cartel is worried." - P.Fuhrman  |  [email protected]  utzoo!henry

Article: 2209
From: [email protected] (Josh Hopkins)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: 12 Jun 1994 22:28:52 GMT
Organization: University of Illinois at Urbana
 
[email protected] (Clayyy) writes:
 
>Will it ever be possible to send nuclear waste to the sun...would the
>payload really be that expensive...considering the alternative.  It
>wouldn't damage the sun...What would the current cost be...any ideas
>on trying to estimate this cost would be much appreciated.  
 
A few notes:  Energetically, it is more difficult to drop a payload into the
sun than it is to launch is out of the solar system.  This may not be the
same as saying that it is more expensive if the dominant means of transport
is solar powered (e.g. solar sails).
 
Right now it is very, very expensive to do something like this.  I'm not
going to attach a dolar value because it depends greatly on exactly what you
do and how much of the payload is waste verses protective packaging.
 
My understanding is that the actual costs are higher for space disposal than
for technically sound disposal on Earth.  However, this is a very political 
question, and it may be that space disposal is more politically palatable and
therefore could proceed despite the cost.  Because of this, some companies 
have looked at the idea as a new market for lower cost launch vehicles.
-- 
Josh Hopkins                                          [email protected]
 
          He who laughs last probably didn't get the joke.

Article: 2212
From: [email protected] (Jordin Kare)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: 12 Jun 1994 23:15:01 GMT
Organization: LLNL
 
In article <[email protected]> [email protected] (Clayyy) writes:
>Will it ever be possible to send nuclear waste to the sun...would the
>payload really be that expensive...considering the alternative.  It
>wouldn't damage the sun...What would the current cost be...any ideas
>on trying to estimate this cost would be much appreciated.  
>
>[email protected]
 
You don't want to send it into the sun.  You want to do almost
anything else:  put it in high Earth orbit, land it or crash it on the
moon, put it in Solar orbit, say between Earth and Venus, crash it
into Venus or Jupiter, or send it out of the Solar system on an escape
trajectory, in roughly increasing order of delta-V required.  Even
sending it out of the solar system takes only about half the delta_V
of crashing it into the Sun. 
 
Given that, yes, it's been studied extensively.  NASA wanted to do it
with the Shuttle back in the 1970s, and designed payload containers that
would survive a worst-case accident.  However, it only made economic
sense if a) you reprocessed the waste and only disposed of the
longest-lived, most toxic isotopes in space, and b) launches were
as cheap and frequent as NASA was predicting for the Shuttle in the
early 1970s, i.e. $10M per flight and >>100 flights per year.  
(Those were the days...).  Oh, yes, and something like 1 chance in 
10,000 of a catastrophic launch failure.
 
I've seen references recently to using waste disposal to provide a
market for an SSTO; I'm dubious.  It still needs reprocessing, and at
the moment the U.S. not only has no reprocessing capability, it is
forbidden by law to develop any.  It's also essentially forbidden by
law from spending money on alternatives to waste burial, as part of
the politics surrounding the Yucca Mountain waste repository. 
 
I've done some design/economic studies for disposing of nuclear waste
with a laser launcher, and it's much better than any alternative I'm
aware of, particularly from the standpoint of demonstrably safe
operation.  Laser propulsion might even be cheap enough to dispose
of "raw" waste without reprocessing.
 
Incidentally, the costs for disposal with laser propulsion range from
a fraction of a mill (0.1 cent) per kWh to a cent or so per kWh 
depending on assumptions; that assumes waste can be launched _out of the
solar system_ for a few $100/kg or less.
 
Also incidentally, a significant fraction of people with whom I have
discussed this object to launching waste out of the solar system
on the grounds that we'd be "polluting space."  Sigh.
 
	Jordin (Nobody's Back Yard!) Kare
 
Disclaimer:  The above comments are my personal views only and do not
represent positions of LLNL, DOE, or the University of California.
 
Article: 2217
From: [email protected] (Peter Venetoklis)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: Mon, 13 Jun 1994 13:34:49 GMT
Organization: Grumman Data Systems-Woodbury
 
In article <[email protected]> [email protected] (Clayyy) writes:

>Will it ever be possible to send nuclear waste to the sun...would the
>payload really be that expensive...considering the alternative.  It
>wouldn't damage the sun...What would the current cost be...any ideas
>on trying to estimate this cost would be much appreciated.  
 
Actually sending stuff _INTO_ the sun is extremely difficult from a 
propulsion standpoint.  This is a common misconception that people seem
to have.  I suppose the idea that the Sun's strong gravity can just pull
stuff down seems reasonable to people who are used to things falling.
 
The problem is that everything on the Earth is going around the Sun
at the same speed as the Earth (about 30 km/sec).  In order for something
to fall into the Sun, you have to get rid of this speed.  Unlike on the
Earth, where you can put on the brakes or open a parachute to get rid of
speed, in space, _slowing down_ is no different from _speeding up_.  There
is nothing out there that _slows you down_.  You have to do it yourself.
 
To give an example of how tough it would be to get rid of most of the 
30 km/sec that we are burdened with, consider that the Pluto Fast Fly-By
mission, which is the equivalent of a cannonball being shot from the 
Earth, probably makes only about 10-15 km/sec leaving the Earth.  PFF
uses a Titan IV, costing $400 million or so, to push less than 400 lbs
to half the speed you need.
 
Gravity assists might help, but there are other problems with the idea.
1) Launching stuff into space is not a sure thing.  A launch failure
runs the risk of exposing the environment to the waste.
 
2) You'd be much better off just putting the stuff into a non-Earth
crossing heliocentric orbit from the propulsion standpoint.  You'd get
mush more mass into orbit this way.
 
3) There are better ways to dispose of radioactive waste.

   I've heard of three separate technologies that convert long-life
waste to short life waste that can be effectively stored until it is 
safe.  In addition, there are approaches that separate out the nasty
stuff from the rest of the material, which can be re-used as fuel.
The actual volume of the bad stuff is small.
 
____________________________________________________________________
Peter Venetoklis                           [email protected]
Senior Engineer - Mission Analysis      Northrop Grumman Corporation
Opinions are mine, not Grumman's, not Northrop's, not anyone else's.

Article: 2227
From: [email protected] (Dick Buenneke)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: Mon, 13 Jun 1994 17:00:16 -0800
Organization: RAND -- Santa Monica, Calif.
 
In article <[email protected]>, [email protected] (Clayyy)
wrote:
 
> Will it ever be possible to send nuclear waste to the sun...would the
> payload really be that expensive...considering the alternative.  It
> wouldn't damage the sun...What would the current cost be...any ideas
> on trying to estimate this cost would be much appreciated.  
> 
> [email protected]
 
You might want to check out a new NASA-sponsored "Commercial Space
Transportation Study."

The executive summary was published in April. Study results can be
obtained from NASA Langley Research Center in Hampton, Va. 
 
The CSTS study was done jointly by six major aerospace companies -- Boeing,
General Dynamics, Lockheed, Martin Marietta, McDonnell Douglas and
Rockwell.  They concluded that space disposal of concentrated nuclear wase
is technically feasible and could be more cost effective than permanent
groud disposal. To make economic sense (when compared with the estimated
$43 billion for ground storage of at least 51,000 metric tons of waste),
ground processing costs would have to be no more than $100 per kilogram,
with launch costs of $600 per kg.
 
Waste would be put on the far side of the moon in this calculation. To send
waste to the Sun would probably require lower launch costs. 
 
And finally, these estimates assume everyone thinks space disposal is a
good idea. If there isn't a consensus, they'll be lots of legal bills and
delays. These additional launch costs also would mandate  launch costs of
less than $300/kg for the concept to be cost-effective.
-- 
Richard H. Buenneke Jr.                    Tel: (310) 393-0411, Ext. 7382 
RAND Graduate School                       Fax: (310) 393-4818
1700 Main Street                             Internet: [email protected]
P.O. Box 2138                                  "All opinions are mine alone
Santa Monica, Calif.  90407-2138      All facts speak for themselves"

Article: 2231
From: [email protected] (Dani Eder)
Newsgroups: sci.space.tech
Subject: Re: Nuclear Waste into the Sun
Date: 13 Jun 94 21:22:07 GMT
Organization: Boeing AI Center, Huntsville, AL
 
In article <[email protected]> [email protected] (Clayyy) writes:

>Will it ever be possible to send nuclear waste to the sun...would the
>payload really be that expensive...considering the alternative.  It
>wouldn't damage the sun...What would the current cost be...any ideas
>on trying to estimate this cost would be much appreciated.  
>
>[email protected]
 
Since I worked with a guy who was paid to study this, I'll comment
(The subject is 'Space Disposal of Nuclear Wastes' and Battelle
Memorial Institute was the contractor.  It was done in the early 1980s)
 
Presumably your goal is to reduce risk to earthlings.  If you have
a fallible space transportation system, and you are trying to launch
something into the Sun (or to Solar System escape) your transport
may fail at the wrong time.  If it does, it may leave your nuclear 
waste in an elliptical orbit that intersects the Earth.  This isn't
so bad, as you probably designed your waste container to survive
reasonable re-entry velocities (in case of launch failure).  But
if the orbit intersects another planet, the waste may be perturbed
into an orbit that intersects the Earth at high velocity, up
to twice the Earth's velocity around the Sun.  This becomes a
very difficult container design problem.
 
Given current space transport failure rates, the safest place
to put the nuclear waste is in a circular solar orbit halfway
between the Earth and Venus (0.85 AU).  It also takes a lot
less energy to get there.  The orbit is stable for long enough
for the waste to decay.
 
The waste is contained in glassified form inside a steel shell
9 inches thick, which in turn is covered by shuttle tile type
exterior.  That way if your launch vehicle fails just before reaching
orbit, the waste ball will re-enter safely.  The steel shell
deforms on impact with the ground, but does not rupture (that's
why it's 9 inches thick).
 
Compared to simply burying these very strong waste balls, the
space disposal option costs about twice as much as hard rock
burial, and avoids only a couple of expected cancer deaths,
based on statistics.
 
The guy I worked with said he would like to have one of the
waste balls buried under his driveway to keep snow melted off
it, since it gives off about 2 kilowatts of heat from the
decay of the waste material, and it would be so rugged that
there was very little risk from the thing (less risk than
an airplane crashing into your house or a stray bullet from
a drive-by shooting detonating the lawn mower's gas tank)
 
Dani Eder
 
-- 
Dani Eder/Rt 1 Box 188-2/Athens AL 35611/(205)232-7467

Article: 2255
From: [email protected] (Kieran A. Carroll)
Newsgroups: sci.space.tech
Subject: Laser Launching Nuclear Waste
Date: Thu, 16 Jun 1994 18:09:01 GMT
Organization: U of Toronto Zoology
 
In article <[email protected]> [email protected] (Jordin Kare) writes:

>I've done some design/economic studies for disposing of nuclear waste
>with a laser launcher, and it's much better than any alternative I'm
>aware of, particularly from the standpoint of demonstrably safe
>operation.  Laser propulsion might even be cheap enough to dispose
>of "raw" waste without reprocessing.
>
>Incidentally, the costs for disposal with laser propulsion range from
>a fraction of a mill (0.1 cent) per kWh to a cent or so per kWh 
>depending on assumptions; that assumes waste can be launched _out of the
>solar system_ for a few $100/kg or less.
 
It seems to me that laser launching is particularly appropriate if your
goal is off-Earth disposal of nuclear waste, because of a feature of
laser launchers that for most other applications seriously limits their
usefulness---the difficulty in scaling up a laser launcher to launch
large payloads. The argument goes like this:
 
- The easiest laser launcher to build is one that launches relatively
small payloads, in the 10s of kilograms range (anything bigger requires
either very large or very many lasers, as well as a very high
peak-load power supply system). 

- It's also easier to build a laser launcher for a payload that's going
to fly straight upwards, rather than one that has to end up flying
tangentially to the Earth's surface (less complexity in the beam pointing
mechanism, and less in-atmosphere path length for the beam).

- Baseline approach: laser launch small packages of nuclear waste
straight upwards, at greater than solar escape velocity. The "spacecraft"
containing the "payload" (i.e., the nuclear waste) need by little more than
the flight end of the laser launch system---that is, it needn't carry any
auxiliary propulsion, attitude control, power, etc. subsystems, because
it will be put directly into the desired trajectory by the laser launcher.

- Why is the small payload size a boon? Becasue it contributes to the
safety of the disposal system---essentially, because each package of
radioactive waste is small, the effects of a launch failure for any one
launch would be small.
 
In launching payloads containing radio-isotopes, failure modes and
effects analyses done in the past have looked at the probability of a
launch failure, the probability of the containment system for the
radioactive material being breached during a crash, and the effects of
the resulting release of radioactive material; basically, these
factors are multiplied together to estimate something like the
probable number of deaths due to the launch (with desirable
probabilities being <<1). If you were to use the Space Shuttle to
launch a cargo bay full of radioactive waste, you' d have a
probability of a launch failure of about 1%, and the total amount of
waste that could potentially be released would be large; the only way
to mitigate the resulting large probable number of deaths would be to
put the waste in a truly awesome containment vessel, to lower the
probability of release following a crash (the mass for this
containment system would of course result in a decrease in the mass of
waste disposed of per launch). With a laser launcher, the probability
of a launch failure could possibly be much less than for a
rocket-powered launcher, due to its inherent simplicity. In addition,
the total amount of waste per launch would be very small, so that the
estimated number of deaths per launch would be correspondingly small. 
 
Can anyone see any flaws in that argument?
 
     Kieran A. Carroll @ U of Toronto Aerospace Institute
     uunet!attcan!utzoo!kcarroll [email protected]

Article: 2271
From: [email protected] (Nick Haines)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: Fri, 17 Jun 1994 15:17:34 GMT
Organization: Harlequin Limited, Cambridge, England
 
In article <[email protected]> [email protected]
(Dick Buenneke) writes: 
 
   [on sending nuclear waste to the Sun]
 
   You might want to check out a new NASA-sponsored "Commercial Space
   Transportation Study."
   [...]
 
   They concluded that space disposal of concentrated nuclear wase
   is technically feasible and could be more cost effective than permanent
   groud disposal. To make economic sense (when compared with the estimated
   $43 billion for ground storage of at least 51,000 metric tons of waste),
   ground processing costs would have to be no more than $100 per kilogram,
   with launch costs of $600 per kg.
 
   Waste would be put on the far side of the moon in this calculation. To send
   waste to the Sun would probably require lower launch costs. 
 
Actually, sending things to the sun is a good deal _more_ expensive
than sending them to the far side of the moon. There's about 30 km/sec
orbital velocity to lose.
 
Nick Haines [email protected]

Article: 2285
From: [email protected] (Dani Eder)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: 17 Jun 94 15:15:22 GMT
Organization: Boeing AI Center, Huntsville, AL
 
[email protected] (Mark Adler) writes:

>I think that all this discussion of the cost of launching nuclear waste
>is missing the real driver: risk.  Even if it were free, it would be
>stupid to launch the stuff when the launch vehicles blow up as often as
>they do.  It's hard to see how even a laser or rail launcher could ever
>be safer than simply burying the stuff in the ground.

The 'Space Disposal of Nuclear Wastes' study that I referred to
assumed conventional rocket launchers, with conventional failure
rates. Part of the study was to do a detailed fault tree analysis,
looking at all the risks of exposure (including accidents in the waste
glassification and encapsulation plant, and in truck transport to the
launch site). 
 
The biggest risk if not accounted for by design, of course, is a
launch vehicle accident.  That's why the waste is put in a stainless
steel shell covered by re-entry tiles - so it can withstand a worst
case launch accident. 
 
The final result was that launching into space avoided an estimated
two (2.0) expected cancer deaths based on the statistical estimates,
compared to in-ground burial.  The space launch was estimated to cost
twice as much as burial.  Since it gave a very small risk reduction
for a big cost increase, it was judged not effective and not pursued
further.  Now, ten years later, some of the assumptions behind the
study will have changed, such as:
 
* How much burial REALLY will cost
* How many reactors there are to produce waste
* Launch technology available 
 
So, if the study were re-run today, I don't know what the answer would be.
 
Dani Eder
-- 
Dani Eder/Rt 1 Box 188-2/Athens AL 35611/(205)232-7467

Article: 2298
From: [email protected]
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: Sun, 19 Jun 94 16:33:14 BST
Organization: CRL Dialup Internet Access
 
> Admittedly, it's been a while since I studied stellar physics, but 
> there used to be a theory that stars went unstable when they 
> started forming iron because the iron had a catalytic effect on 
> other, undesirable reactions. 
 
Stellar fusion occurs only in the core. The surface areas have 
temperatures and pressures that are far too low for any sort of 
fusion to occur.
 
The effect you are discussing has to do with the late life of massize
stars (O, B, maybe A). They rapidly burn up their core Hydrogen and 
in the process synthesis higer elements. Then the next higher element
it leaves an ash of still higher weight elements and so forth. This  
results in a series of shells of materials proceeding outward from 
the core. The procession from one reaction to another proceeds at an
accelerating rate. Where hydrogen burning may last most of the life 
time of the rather short lived star (O and B are not known for their  
longevity) the final reactions occur in months and then days.
 
Fe is the ultimate ash of nuclear reactions. The binding energies are 
such that iron fusion takes mor energy than it gives off. So the near
death time of stars is a growing iron core that is an energy sink 
rather than an energy source. Now a star is a massive ball of plasma. 
 
O,B and A types are very massive balls of plasma. Gravitaty would
tend to compress them to solids, then degenerate matter, then  
neutronium and finally into a black hole if not for the radiation  
pressure generated by the fusion reactions in the core.
 
When the Fe core reaches a critical mass, it begins this implosion.  
How far it goes depends greatly on the initial mass of the star. In
any case, the implosion is "supersonic". I will not go into the  
details about rebounds, shockwave stalling etc -- in short, the
implosion generates shockwaves that travel back out of the iron core
and blow the envelope off the star. That is a supernova.
 
The amount of aterials that we would drop onto the surface of the sun 
at this time in our technological development are insignificant. The
total mass of our entire planet Earth is insignificant. We could be 
dropped into a sunspot with little more than a bit of a flare. About
the only detectable result would be a slight change in some lines in 
the solar spectra.
 
Let's assume that is what we did. Now the Earth has a nice big iron  
core. Relative to us, not relative to the sun. If it were massive  
enough to implode gravitationally, we wouldn't be here to discuss it.
As a side thought, I wonder how many seconds the Earth would last on
the "surface" of Sol?  A type G star is roughly 3000 C. Don't have Me 
handy. I'd guess a good back of the envelope would be to assume 1/2 
silicate rock and 1/2 nickel iron. Get the heats of fusion for 
solid-liquid, liquid-vapor and the energy input per degree for each 
phase; hmmm we can't just assume a blackbody because we also have 
conduction and convection....
 
Oh, well... Sounds like a good homework problem :-)
--
=======================================================================
      Individual Liberty	     Dale M. Amon, The only libertarian
   Individual Responsibility	 	   in Northern Ireland
  R.Means, 1988 LP Convention    	    [email protected]
=======================================================================

Article: 2300
From: [email protected] (Josh Hopkins)
Newsgroups: sci.space.tech
Subject: Re: Why not...
Date: 19 Jun 1994 20:44:37 GMT
Organization: University of Illinois at Urbana
 
"Charles Radley " <[email protected]> writes:
 
>An ever better site is the Moon.   No aquifers, no weather, no ecosystem,
>very little seismic activity.  The surface is a high radiation environment
> already (solar and cosmic radiation).
 
>Much less energy to get there than the Sun.
 
>Permanent manned presence would be required to ensure security of 
>the site.
 
I agree about the choice of the Moon, but I'm skeptical about the need
for security.  Any third world nation or terrorist group that can
steal nuclear material from the far side of the Moon has the resources
to get it on Earth more easily.  Moreover, adding an actual base
there, with security staff on site makes it easier, not harder to get
the stuff. 
-- 
Josh Hopkins                                          [email protected]
 
          He who laughs last probably didn't get the joke.

Article: 2276
From: [email protected] (Jordin Kare)
Newsgroups: sci.space.tech
Subject: Re: Laser Launching Nuclear Waste
Date: 17 Jun 1994 18:18:04 GMT
Organization: LLNL
 
In article <[email protected]> [email protected]
(Kieran A. Carroll) writes: 

>In article <[email protected]> [email protected] (Jordin Kare) writes:
>>I've done some design/economic studies for disposing of nuclear waste
>>with a laser launcher, and it's much better than any alternative I'm
>>aware of, particularly from the standpoint of demonstrably safe operation.
>
>It seems to me that laser launching is particularly appropriate if your
>goal is off-Earth disposal of nuclear waste, because of a feature of
>laser launchers that for most other applications seriously limits their
>usefulness---the difficulty in scaling up a laser launcher to launch
>large payloads. The argument goes like this:
>
>- The easiest laser launcher to build is one that launches relatively
>small payloads, in the 10s of kilograms range (anything bigger requires
>either very large or very many lasers, as well as a very high
>peak-load power supply system). 
 
This is a bit of an exaggeration.  Laser systems scale up slightly
better than linearly (i.e., they get cheaper per pound launched as
in both capital and operating cost as they get bigger) which is about
the same scaling as rockets.  There's no particular problem building
laser systems to launch, say, 1-ton payloads, and the capital cost is
probably of order $10-20 billion -- comparable to the Shuttle.  But
except for nucwaste disposal, even I have a hard time figuring out what
to do with the payload capacity of a 1 ton launcher in the near term:
30,000 tons per year.  What is unusual is that laser launchers scale _down_
to 10's of kg payloads without problems....
 
>- It's also easier to build a laser launcher for a payload that's going
>to fly straight upwards, rather than one that has to end up flying
>tangentially to the Earth's surface (less complexity in the beam pointing
>mechanism, and less in-atmosphere path length for the beam).
 
True, although again not a big effect....
 
>- Baseline approach: laser launch small packages of nuclear waste
>straight upwards, at greater than solar escape velocity.
 
Actually, what you need to do is launch straight "forward" along
Earth's orbit, within a fairly small angle.  Thus, depending on 
what fraction of the day you want to operate over, you need to launch
at a significant angle to straight overhead.  For economy, you want
to launch for close to 12 hours a day, reqiring at least as much
flexibility as an orbital launcher.  (Launching at much of an angle
to the Earth's orbit requires _much_ more delta-V
 
 The "spacecraft"
>containing the "payload" (i.e., the nuclear waste) need by little more than
>the flight end of the laser launch system---that is, it needn't carry any
>auxiliary propulsion, attitude control, power, etc. subsystems, because
>it will be put directly into the desired trajectory by the laser launcher.
>- Why is the small payload size a boon? Becasue it contributes to the
>safety of the disposal system---essentially, because each package of
>radioactive waste is small, the effects of a launch failure for any one
>launch would be small.
 
This is the general idea.  
 
There is a messy issue associated with shielding the payload: 
radiation shielding must be of a fixed thickness essentially
independent of the amount of radioactive material shielded (i.e., the
difference between 10 absorption lengths and 12 isn't very big...) 
For a large (shuttle-scale) payload, the rad shielding isn't a big
problem.  For a 1-ton laser propulsion payload, something like 50% of
the mass is shielding (at a minimum).  For a 10-kg payload, you
_can't_ shield the waste enough to eliminate hazardous radiation. 
 
This isn't a problem for launching (just use robot/teleoperated loading)
but is a major problem in meeting regulatory requirements, especially
with regard to accidents.  It becomes a problem of what risks are
acceptable to the regulatory agencies....

>In launching payloads containing radio-isotopes, failure modes and
>effects analyses done in the past have looked at the probability of a launch
>failure, the probability of the containment system for the radioactive
>material being breached during a crash, and the effects of the resulting
>release of radioactive material; basically, these factors are multiplied
>together to estimate something like the probable number of deaths due to
>the launch (with desirable probabilities being <<1). If you were to use
>the Space Shuttle to launch a cargo bay full of radioactive waste, you'
>d have a probability of a launch failure of about 1%, and the total amount
>of waste that could potentially be released would be large; the only way to
>mitigate the resulting large probable number of deaths would be to put the
>waste in a truly awesome containment vessel, to lower the probability of 
>release following a crash (the mass for this containment system would of 
>course result in a decrease in the mass of waste disposed of per launch).
 
Such containment vessels are exactly what were designed.  To give an idea,
the Shuttle payloads were designed to withstand landing on railroad tracks
and being run into by a locomotive, landing in a blast furnace, etc.
And of course, at the time, the P(failure) for Shuttle was estimated 
at more like 10E-4 than 10E-2.
 
 With a laser launcher,
>the probability of a launch failure could possibly be much less than for a
>rocket-powered launcher, due to its inherent simplicity. In addition,
>the total amount of waste per launch would be very small, so that the
>estimated number of deaths per launch would be correspondingly small.
 
There are three additional benefits to a laser launch vs. a rocket:
 
1.  No energetic propellants, hence no risk of explosion.  A large fraction
	of the hazard analysis for radioistope power sources involves
	figuring out the worst possible combination of blast and shrapnel
	from various kinds of explosive failures and making sure they
	won't shred the containment.  
 
2.  No energy stored on board, hence no "wild" flights.  The trajectory
	and impact point are always predictable to high accuracy even
	if the laser fails/loses track abruptly.  With some effort, you
	can select the impact point ground track to avoid, e.g., 
	population centers.
 
3.  Very high launch rate allows very extended testing of _both_
	launch system _and_ emergency reentry/recovery systems before
	"loaded" launch.

>Can anyone see any flaws in that argument?
 
Sounds good to me :-)

>     Kieran A. Carroll @ U of Toronto Aerospace Institute
>     uunet!attcan!utzoo!kcarroll [email protected]
 
	Jordin (Ask Mr. Laser) Kare

    Everyone keeps talking about having to "lose" 30km/s of velocity. That
    would be true if you insist on a straight "fall path" trajectory into
    the sun. What about a spiral path? If you reduced the velocity by about
    5 km/sec would the spiral path do the job? Agreed, it would be
    necessary to reduce the velocity sufficiently that you avoid
    "retrieving" the mass into the earth's gravity well in 12+ months, but
    I don't see the need to drop the whole 30 km/sec.
    
    I guess I'm missing something about orbital mechanics.
    	Rob Wall
    	Kanata Manufacturing Engineering Support 621-4407
    

Ignore for a moment the fact that we have to get OUT of Earth's gravity well and
the fact that there are other bodies in the solar system besides the trash and
the sun.  If you have a body in a circular orbit (as the trash would be around
the sun if we magically ignore the Earth) and you slow it down at one point in
its orbit, the orbit changes from circular to elliptical, with the point where
the slowdown occurred the apohelion and the point opposite as the perihelion. 
No spiral, just an ellipse.

If the slowdown you do at aphelion is the entire orbital velocity, then the
perihelion distance is 0 (i.e. the center of the sun).  The less you slow it
down, the further from the sun is the perihelion.

So very roughly, you need to slow the beast down enough so that it's perihelion
is close enough to the sun so that it will "aerobrake".  I don't have the
formulae off the top of my head to calculate how much delta V is required to
lower the perihelion by a certain amount, but it seems like it would need to be
more than 5 km/sec (which is only a 16% change in the circular orbital velocity).

  As some of the internet notes have suggested, the real problems here are
political. Environmentalists go ballistic when ever JPL wants to launch a deep
space satellite with a small amount of nuclear fuel because they are afraid
that it would contaminate the atmosphere on a launch failure. 

  Now if you wanted to launch tons of nuclear waste on a regular basis, and if
you use the 95% success rate for launch, you have to figure that 1 out of every
20 attempts will result in some sort of headline that you probably would not
want to read. 

  George