Digest 1105 Msg 7

http://www.vivoscuola.it/us/mscvni10015/Web/Casa%20BiancaR.htm
maybe we can get the best of two worlds with the
following consideratiions:
thereason I propose a deflected asteroid as spaceship
on a cycler trajectory is due to one factor: asteroid
have resources that can be utilized in space, solar
sails don't.
But solar sails as you proposed, with the right
modifications could be the best propulsion system for
small asteroids, even the 10\20\30000tons which would
be big enough to supply what necessary.
The asteroid would be equipped with the astrohab
system, see the link above, and would work as a hotel
plus life support production facility.
On a cycler orbit between earth, the moon , mars or
other locations this could be the most affordable
solution with existing technology.
I don't foreee asteroid mining to bring the material
back to earth.
We have all the needed materials here already at a
fraction of the cost compared to space produced ones.,
but i can see the utilization and minimg of asteroids
in space, to supply all needed materials for
spacesettlements and space manufacturing..

--- Frank nd@... ha scritto:

>I agree with many of your arguments
>i am suggesting to deflect a small asteroid about
>100000 ton mass , arond 30\50meters diameter not a
big
>one

if you make the diameter a bit smaller, about 15\25
meters the
Solar-Thruster-Sailor design I propose could take that
asteroid into
its central payload ring-structure.

With winches on this ring and a laser unit to melt the
water ice to
place anchors it could safely hold that asteroid in
its center.

The problem I see is the high mass, even if it is only
20000 tons it
is way too much. For a solar sail of my design I would
estimate
maximal only 100 tons of mass for one single payload.

So take a look onto a chemical rocket were 90 % of the
mass is for
fuel. You would put out the biggest part of the
asteroid material for
propulsion only while you can get 100 % of that
material back to Earth
with solar sail container- or tug-ships in a lot of
smaller charges.

Frank

www.solar-thruster-sailor.info

For the first solar sail design of a carrier ship with
docking able
landers and with roller reefing

making it possible to leave the atmospheric drag zone
near a space
station and getting back again delivering asteroidal
ore to that
Near Earth space station

take a look at:

www.solar-thruster-sailor.info/figs/fig13.html

http://www.solar-thruster-sailor.info/figs/fig14-15.html

http://www.solar-thruster-sailor.info/figs/fig17.html