^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------------------------------
Date: Tue, 28 May 1996 00:57:26 -0400
From: KellySt@aol.com
To: kgstar@most.fw.hac.com
Subject: e=mc

Subj: Re:Antimatter production
Date: 96-05-27 04:05:06 EDT
From: FrankEReed

"When matter and antimatter meet and anihilate each other, I know
released energy in Newtons is equal to the total mass in kilograms times
the speed of light in meters per second squared."

Yes, that's right. One small correction, the S.I. units for energy are joules,
not newtons. So take mass in kilograms, multiply by c in meters per
second squared, and the result you get is joules. You can divide that by
3,600,000 to get units of kilowatthours instead. This can be useful since
it gives you an idea of the current value of the energy involved. (1kWhr
costs about $0.10).

"But is it possible to convert matter into antimatter for this reaction
while expending less than twice as much energy as the matter/antimatter
reaction releases -- thereby ending up with a net surplus of energy?" 

Alas, no. It's possible to show that if you could do this you would be able
to generate infinite energy. There are extremely strong theoretical and
experimental reasons for believing that energy is always conserved. 

" Is this as nonsensical an idea as a perpetual motion machine?" 

Yes, it's the same thing as a perpetual motion machine. 

Of course, there's no real problem here. We *can* make antimatter and in
principle we can make vast quantities. Wallpaper the Moon with solar
cells. Hook 'em up to accelerators and collect the antimatter. :) 

-FER




^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0
Date: Fri, 31 May 1996 14:28:59 +0100
To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, 
jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl,
hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com,
David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com,
neill@foda.math.usu.edu, 101765.2200@compuserve.com,
MLEN3097@Mercury.GC.PeachNet.EDU
From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) 

Subject: Re: more physics (short)

Better late then never...

>Fuel --> Exhaust	Watts /
>kg

>p + 11B --> 3 4He	6.926 E13	11,800,000 m/s
>De + 3He --> 4He + p 3.505 E14	26,500,000 m/s
>*
>6Li + 6Li --> 3 4He
>(Combined)	1.596 E14	17,800,000 m/s
>**
>3He + 3He --> 4He + 2 p
>2.059 E14	20,300,000 M/s
>***

>This all seems pretty straight forward, but then I noticed we had
previously come up with exaust velopcities of: 

I don't remember seeing the numbers you mention but when you are using 
E=0.5 m v^2 the above numbers are correct. 

Keep in mind that the efficiency is probably far below 100% (Don't ask
how we get rid of the waste energy)


Timothy








^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------------------------------
X-Sender: kgstar@pophost.fw.hac.com
Mime-Version: 1.0
Date: Fri, 31 May 1996 08:19:26 -0500
To: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden) From:
kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39) 

Subject: Re: more physics (short)
Cc: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, 
jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl,
hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com,
David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com,
neill@foda.math.usu.edu, 101765.2200@compuserve.com,
MLEN3097@Mercury.GC.PeachNet.EDU

At 2:28 PM 5/31/96, Timothy van der Linden wrote: 
>Better late then never...

>>Fuel --> Exhaust	Watts /
>>kg

>>p + 11B --> 3 4He	6.926 E13	11,800,000 m/s
>>De + 3He --> 4He + p 3.505 E14	26,500,000 m/s
>>*
>>6Li + 6Li --> 3 4He
>>(Combined)	1.596 E14	17,800,000 m/s
>>**
>>3He + 3He --> 4He + 2 p
>>2.059 E14	20,300,000 M/s

>>***

>>This all seems pretty straight forward, but then I noticed we had
previously come up with exaust velopcities of: 

>I don't remember seeing the numbers you mention but when you are using 
>E=0.5 m v^2 the above numbers are correct. 

>Keep in mind that the efficiency is probably far below 100% (Don't ask
how we get rid of the waste energy)


>Timothy

Thanks!

I went over the Bussard paper and found 14E6 as the upper exaust vel for p
+ 11B. Which obviously isn't what I'm getting. Eiather I miscalculated the
watts per Kg (I sent my equations for that in another letter) or I misread
Bussards paper. (I suppose I could write him.) I'ld hate to write off about
15% of spec impulse if I didn't need to. (See table below.) 

If you know how to get the exaust speed from Mev numbers let me know.
I'm sure those numbers from the papers are correct. 

I was working up the following table of the fuel mass ratios needed to get
to or from certain speeds given the exaust velocities. 

NEW numbers

Fuel --> Exhaust
Vexh	75E6m/s	100 E6m/s 125 E6m/s 150 E6m/s

p + 11B --> 3 4He
11,800,000 m/s	576.0	4,790.0 39,900 332,000

6Li + 6Li --> 3 4He
(Combined)
17,800,000 m/s	67.6	275.0	1,120	4,570

3He + 3He --> 4He + 2 p
20,300,000 M/s	42.5	138.0	472	1,620

De + 3He --> 4He + p
26,500,000 m/s	16.9	43.5	112	287


Old numbers ====================================================
Fuel type
Exhaust speed	75E6m/s 100 E6 m/s 125 E6m/s 150 E6 m/s
p + 11B --> 3 4He
14,000,000 M/sec	212.0	1,270	7,540	45,000

De + 3He --> 4He + p

6Li + 6Li --> 3 4He
21,000,000 M/sec	35.6	117	384	1,270

3He + 3He --> 4He + 2 p
24,000,000 M/sec	22.8	64	183	518




Amazing how touchy the fuel ratios are to changes in exaust vel/specific
impulse. Look at the difference between 6Li + 6Li and 3He + 3He! ;) 

Anyway I'm roughing out some numbers for a combined microwave sail
fusion ship. The big limitation with my Explorer class is the fuel
launchers range. The ship can't boost out once its to far away to get
acceleration fuel from the sol launchers. That means it needs a high power
to weight ratio to get to speed in a short distence. Given the huge weights
of fuel needed to slow down that gets rediculas pretty fast. The
microwave/laser sail ideas on the other hand can't slow down. I figured if
I used a Microwave sail to accelerate the ship. It could accelerate more
slowly over a longer range. Given that deceleration rates arn't as crytical
(and litium doesn't need a tank) the craft could burn down even if it had
huge (maybe 300-400 to 1) fuel ratios. That could allow a maximum speed
of almost .4 c! That would get you to Alpha C in about 11 years! 

Kelly


---------------------------------------------------------------------- 

Kelly Starks	Internet: kgstar@most.fw.hac.com
Sr. Systems Engineer
Magnavox Electronic Systems Company
(Magnavox URL: http://www.fw.hac.com/external.html) 

----------------------------------------------------------------------




================================================================
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Date: Sat, 01 Jun 1996 17:21:08 +0100
To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, 
jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl,
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MLEN3097@Mercury.GC.PeachNet.EDU
From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden)
Subject: PROBLEMS WHEN USING A ELECTROMAGNETIC BEAM TO PROPELL A
STARSHIP 

Hi guys,

The last few weeks I've been working at a summation of the beaming
problems. Most is what I can recall from earlier discussions, some things
I thought of when writing this summary. I hope I did an objective job, if
not tell me and I'll try to fix it. Also the list of solutions and advantages
is not very big, it would be nice to balance the text a bit more
(unfortunately we came up with much more problems than solutions). 

Timothy




PROBLEMS WHEN USING A ELECTROMAGNETIC BEAM TO PROPEL A STARSHIP 

June 1st, 1996 Timothy L.G. van der Linden 

The following is a summation of problems regarding beaming. This
summation is an overview about what has been discussed in the Starship
Design group. 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

The idea:

A laser beaming station situated in our solar system transfers momentum
and energy to the starship that flies towards an other solar system. To
accelerate the starship a huge sail attached to the starship reflects the
beam.
To decelerate the starship there are two possibilities: The energy of the
beam is used by an engine at the starship which exhausts mass (which was
carried by the starship) to decelerate the starship. The other possibility
is to use some form of retro-reflection, here a second sail/mirror is used
to reverse the direction of the laser-light so that seen by the starship the
laser light comes from the other solar system. 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

Possible problems:

1 Beam jitter (Earth end)
2 Following the beam (starship end)
3 Creating the beam
4 Diffraction of the beam
5 Attenuation of the beam
6 Efficiency of the lasers is small (<1%) 7 Stopping the starship (a. retro-
mirror or b. energy transfer) 8 Using EM-radiation as momentum-carrier is
less efficient then using matter. 9 Red shift causes the momentum to
decrease 10 Reflectivity of the sail is less than 100% 11 Construction of
the beaming station at the other solar system (and at home) 12
Construction of the sail/mirror
13 Protection of the starship against the beam 14 Communication with
Earth

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

Explanations:

1 The beaming station very likely needs to be build on a moving/rotating
object like a planet, moon or asteroid. This calls for aiming devices that
may not always be 100% accurate. Even very small deviations may cause
enormous deviations after several lightyears. 

2 Staying inside the beam may not be that easy if the beam is narrow. If
the beam has an uneven distribution of momentum/energy for some period,
the whole starship will then be turned, which makes the problem even
worse. One could compare this with the rudder of a ship. 

3 A single laser/maser of many kilometres wide is unlikely to be build,
instead many smaller lasers will be used. It may be necessary to get them
all lined up and all in phase so that interference is decreased. All lasers
need to be powered and controlled separately. 

4 Small apertures and long wavelengths of the lasers cause widening of
the beam, this is a well known effect. In normal situations a laser may
look like a point but over distances of several lightyears this widening
may become problematic.

5 Probably the smallest effect, the amount of dust may not be that much
compared to the power that is needed. The beam itself will push away a
lot of the dust so that the path is "smoothed" a bit. 

6

7a The retro-mirror needs to be free from the ship, this means it needs
its own navigation and control system. Since this mirror cannot be
recovered it has to be completely self-maintaining.
The retro-mirror needs to have a significant mass (comparable to that of
the starship) otherwise its speed will get so high that distance and
Doppler shift will be significant problems.
Directing the retro-mirror precisely may rise problems. Also having the
mirror, the starship and the beaming-station in one line may cause
problems with beams that go back and forth in the same line and thus
make it difficult to use the right beam to decelerate. Another idea is the
use of a "non-solid" retro-mirror, here a cloud of plasma is pushed in front
of the ship, this cloud should reflect the beamed EM-radiation (in this
case microwaves) back to the starship. There are several problems that
come with this idea. 

7b The beam tries to accelerate the ship. This means that before the ship
can decelerate by its own "deceleration structure", it has to overcome the
accelerating power of the receiving photons. Calculations have shown that
this is possible.
A problem that may need solving is the conversion of energy from
photonic-energy to energy that can be used by the engine. Some have come
up with ingenious systems to get around that problem. Apparent
disadvantages are that the ship needs to carry the exhaust mass and needs
some structure to accelerate the exhaust mass. The reason for being
unclear about the "engine" or "deceleration structure" is that some have
come up with a structure to directly transfer the momentum of the
photons to the exhaust mass.

8 While reflecting the laser energy transfers approximately two times the
momentum of the photons is transferred to the starship, using matter
(small particles) as momentum carrier may be more efficient. Photons
have a constant energy:momentum ratio, for matter this ratio depends on
the velocity of the particle but it is always better than for photons. 

9 Red shift is especially important when the starship reaches relativistic
velocities, it causes that the momentum transfer of the photons decreases
and therefore decreases the efficiency.

10 The energy density of the beam has to be limited because the reflection
of the beam by the sail on the starship is not 100% reflective, so it will
absorb a small fraction of the energy. The amounts of energy may be so
high that the sail could melt.

11 Since the starship relies on an external energy source, the return flight
needs an other beaming station, which needs to be build inside the other
solar system, needless to say this involves a lot of infrastructure. A
beaming station should be visualized as a large array (100-1000? square
kilometres) of large highly accurate powerful lasers and a lot of fusion
reactors.

12a Especially when the accuracy mentioned in 1 and 2 is low, the size of
the sail may be big, it needs to have the strength to pull or push a
starship. Large sails may become very heavy (some scenarios predict many
factors of 10 heavier as the ship itself). 12b It would be preferable that
the sail is at the Earth-side of the ship, this way the ship itself is not
"shined" upon (and not heated). This also means the sail needs to push the
starship which may be more difficult than the pull (parachute) method.

13 There are designs that require the sail to be not on the Earth-side, thus
having the ship in the way. This means the ship needs to be shielded by a
separate mirror/deflector.

14 Communication to Earth may be difficult because the beam effectively
removes every save place to put up an antenna/dish, this is will be caused
by heat overload or severe interference. Communication from Earth may
have some difficulties too, while the sail could be used as a receiver it is
uncertain if the signal-to-noise ratio is very well.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

Solutions:

1 & 2 Widening of the beam.

4 Increasing aperture and/or decreasing wavelength (eg. use IR or gamma
radiation)

14 Use satellites that move parallel with the starship but are outside the
beam. This way the satellites can be used in a similar way as Earth's
communication satellites to reach the othersider of the globe. 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

Advantages:

1 Theoretically less energy needed, because the fuel itself does not need
to be accelerated with the starship like in "normal" rockets. 

2 The ship doesn't need to carry an engine (this may not be true for the
deceleration phase). This may increase the simplicity of the ship and thus
the reliability. This implies that less personnel may be needed.

================================================================
X-Sender: S9421793@mail.student.utwente.nl Mime-Version: 1.0
Date: Sun, 02 Jun 1996 18:37:46 +0100
To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, 
jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl,
hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com,
David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com,
neill@foda.math.usu.edu, 101765.2200@compuserve.com,
MLEN3097@Mercury.GC.PeachNet.EDU
From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden)
Subject: Re: more physics (short)

>I went over the Bussard paper and found 14E6 as the upper exaust vel for
p + 11B. Which obviously isn't what I'm getting. Eiather I miscalculated
the watts per Kg (I sent my equations for that in another letter) or I
misread Bussards paper. (I suppose I could write him.) I'ld hate to write
off about 15% of spec impulse if I didn't need to. (See table below.) 

>If you know how to get the exaust speed from Mev numbers let me know.
I'm sure those numbers from the papers are correct. 

Watch carefully:

The reaction as found in my tables book: 

H + 11B --> 3 4He + 8.7 MeV

Let's assume energy conversion is 100% and ALL reaction products will be
accelerated in the 100% effective lineac. 

First turn MeV in to Joules:

8.7 MeV = 8.7E6 * 1.602E-19 = 1.394E-12 Joule 

Then determine the weight of the particles in kg: 

H + 11B is approx 12 u (u=atomic mass unit) 

12 u = 12 * 1.661E-27 = 1.993E-26 Kg

Thus the energy per kg is:

1.394E-12 / 1.993E-26 = 6.995E13 J/Kg

(Don't use much more significant numbers, if you do use them you need to
define some things more accurate and cannot simply think that 11 H
weighs as much as 11B.)

Using E=0.5 m v^2 I still get v=11.8E6 m/s, so I really wonder how Bussard
can get a higher velocity, unless he dumps some of the reaction mass
instead of accelerating it.

>I was working up the following table of the fuel mass ratios needed to
get to or from certain speeds given the exaust velocities. 

>NEW numbers

>Fuel --> Exhaust
>Vexh	75E6m/s	100 E6m/s 125 E6m/s 150 E6m/s

>p + 11B --> 3 4He
>11,800,000 m/s	576.0	4,790.0 39,900 332,000

>6Li + 6Li --> 3 4He
>(Combined)
>17,800,000 m/s	67.6	275.0	1,120	4,570

>3He + 3He --> 4He + 2 p
>20,300,000 M/s	42.5	138.0	472	1,620

>De + 3He --> 4He + p
>26,500,000 m/s	16.9	43.5	112	287

Of course ;) I get completly different numbers (at least for higher Vend) 

674 2,680 82,000 1,200,000
73 181 1,728	10,000
44	97	708	3,377
18	34	154	509

I assume this time relativistics is the origin (for 0.5c gamma=1.15 which
means its not almost equal to 1 anymore) for our differences 

>Amazing how touchy the fuel ratios are to changes in exaust vel/specific
impulse. Look at the difference between 6Li + 6Li and 3He + 3He! ;) 

Well yes, that is because of the energy per kilogram of fuel. Which is 3
times higher for 3He + 3He. (This is what my "magic" number f says) 


Timothy

================================================================
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Date: Sun, 02 Jun 1996 18:37:38 +0100
To: KellySt@aol.com, kgstar@most.fw.hac.com, stevev@efn.org, 
jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl,
hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com,
David@InterWorld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com,
neill@foda.math.usu.edu, 101765.2200@compuserve.com,
MLEN3097@Mercury.GC.PeachNet.EDU
From: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden)
Subject: Re: PROBLEMS WHEN USING A ELECTROMAGNETIC BEAM TO PROPELL
A STARSHIP 

Kevin, thanks for your comments, I've a few questions regarding your
comments, they include phased arrays, efficiency and diffraction. Well,
read on and you'll see them.

Timothy



>Seems objective enough. One main point though, I would use a MASER, not
a laser while this increases the cost for the beaming station (conversion
of sunlight into electricity ~ 10%) Conversion of electircity into
microwaves and microwaves into electricity are both about 90%. Use of
Masers, allows phased array solutions.

I tried to keep it in the middle (laser or maser), at some places I even
used EM-beams. I don't understand the explanation with your numbers
above: You say the cost of a beaming station increases because the
conversion from sunlight into electricity is ~ 10%, but masers don't need
electricity too? I can understand that phasing is easier with longer
wavelengths, so I will mention that somewhere in a discussion of what
kind of EM-radiation to use. How did you get the numbers of 90%, I'd like to
add a source. 

>>1 The beaming station very likely needs to be build on a moving/rotating
object like a planet, moon or asteroid.

>possible solutions: 1) Multiply the number of separate beaming stations,
thus, while some small number might be deviating, most will be on track
most of the time. 2) use phased array antenna to increase response time of
the beam. 

I'm not sure about (1), because a beaming station already consists of many
smaller masers. Isn't this the same as increasing the size of the beam? 

About (2) I don't understand how changing phase can deviate the direction
of the beam slightly. Lee already told me about it, but I don't understand
what physical phenomenon is behind it (is it interference?). Is there
anyone who can help me here?

>>2 Staying inside the beam may not be that easy if the beam is narrow. 

>Possible solution, slight tilting of the sail at the ship's end... 

Yeps, forgot that one.

>>3 A single laser/maser of many kilometres wide is unlikely to be build,
instead many smaller lasers will be used. It may be necessary to get them
all lined up and all in phase so that interference is decreased. All lasers
need to be powered and controlled separately. 

>solution: Phased array

I think I was seeing a phased array as a problem on itself here. 

>>4 Small apertures and long wavelengths of the lasers cause widening of
the beam, this is a well known effect. In normal situations a laser may
look like a point but over distances of several lightyears this widening
may become problematic.

>Solution: Phased array. By conecting two transmitters many hundreds of
kilometers apart, one can simulate a single arperature with the same
baseline. 

I cannot believe this is completely true. More (phased) sources can indeed
decrease diffraction effects, but does one extra source have so much
effect? Does anyone know this for certain by head? Otherwise I'd need to
calculate it myself (which I don't like at the moment). 

>>6

>efficiency of masers is high? Unknown by me. I do know that microwave
generation is efficient, but masers may not be. Anyone have any data? 

Yes, I don't know very well either, the only number I could find this far
was that of 1% but that book was already old. It would be nice to have
several numbers for varying wavelengths. 

>A reason to use a Lineac decell stage instead of a retro mirror. 

Yes, we know the retro mirror had many difficulties, but the idea is to big
to leave out.

>>9 Red shift is especially important when the starship reaches
relativistic velocities, it causes that the momentum transfer of the
photons decreases and therefore decreases the efficiency.

>But the time dialation on the ship cancels this effect, does it not? That
is to say that while the ship is recieving 1/7 (@ .99 C) of the energy, it
also has 7 times more time to collect that energy (from the viewpoint of
the ship)

Yes that is true, but it still means that relative to Earth the efficiency
decreases. Since all energy has to come from Earth (and they have to pay
for it) that is the most important reference point. The intensity of the
beam is probably not constant anyway, I assume that when the ship is
farther away from the source, the losses are greater and the intensity
needs to be increased. 

>>A beaming station should be visualized as a large array (100-1000?
square kilometres) of large highly accurate powerful lasers and a lot of
fusion reactors.

>or square mega-meters of Solar cells

Yes, but that is another chapter.

>>12a Especially when the accuracy mentioned in 1 and 2 is low, the size
of the sail may be big, it needs to have the strength to pull or push a
starship. Large sails may become very heavy (some scenarios predict many
factors of 10 heavier as the ship itself). 

>I thought I covered this problem already. The use of multiple attachment
points, as many as one every 10 meters, for the sail (As opposed to the
circumfrence only) reduces the pull to a very small amount. 

Yes, I know, but that doesn't decrease the weight of the sail, which may
become a crucial point in the whole design. I'll add this in the solution
section.

>>14.
>communication to earth should use another portion of the EM spectrum,
like the visible portion perhaps.

Yes, but where do you put the sending/receiving antenna? If they are
inside the beam they are likely to be ionized.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Solutions:

>>4 Increasing aperture and/or decreasing wavelength (eg. use IR or
gamma radiation)

>I think increasing the arperature will be far more productive than 
shortening the
>wavelength.

Maybe both can add their share, also see the comment above (by problem
4). 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Advantages:

>>2 The ship doesn't need to carry an engine (this may not be true for the
deceleration phase). This may increase the simplicity of the ship and thus
the reliability. This implies that less personnel may be needed. 

>3) Ship can accelerate continously, taking advantage of the time dialation
effect. and providing the crew with a near normal gravity environment 

Are other designs like fusion engines not able to do this? (in theory) The
advantages of time dilations are not clear to me (see also 9) 

>4) the beaming array only needs to be on for about two years. then it can
be used to send out other ships, or the energy could be used to power
mining operations in the trans astreroid portion of our own system. 

I wonder if the mining will be cost effective if that much energy is
needed. But I will mention the possible re-use effect. 

>5) while the return system will be costly, once built, it will allow much
smaller ships to travel back and forth between the two systems. 

Yes, this is an advantage that may simplify futere missions significantly.


===============================================================

Date: Sun, 2 Jun 1996 23:20:39 -0400
From: KellySt@aol.com
To: T.L.G.vanderLinden@student.utwente.nl, kgstar@most.fw.hac.com, 
stevev@efn.org, jim@bogie2.bio.purdue.edu, zkulpa@zmit1.ippt.gov.pl,
hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com,
David@interworld.com, lparker@destin.gulfnet.com, DotarSojat@aol.com
Subject: Re: PROBLEMS WHEN USING A ELECTROMAGNETIC BEAM TO PROPELL
A STARSHIP 

Not a bad summary Tim. ;) We'll have to work that into the web site (when
we get one). I've been thinking of seting it up on my AOL account space
since Daves always busy, but it might be to big for my account limits. 

Kelly.