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  A Mars Shuttle for $10 Billion

     

The following paper is 10 pages long.  You are free to print it out from here or you can order it at a cost of $3.00.

        
                     A Mars Shuttle for $10 Billion

              A new and much less costly plan has been developed
          to establish a Mars shuttle based upon a new propulsion
          system and robot technology.  This plan will be largely
          self-supporting which is why its cost is so low. This plan
          begins by establishing LEO refueling stations which will
          later be expanded into large habitable space stations. Next
          an unmanned lunar base will be established which will sub-
          sequently be expanded into a manufacturing facility.  This
          facility will provide the parts from which following facil-
          ities will be built using robot labor.  The spaceships will
          be assembled in high earth orbit, again by robot labor. The
          first Mars mission will carry a crew of 1000 to Mars in
          about five weeks.  The crew will spend two years on Mars
          before returning to Earth.  Since the spaceship itself
          will not land at either destination, it will be reusable,
          and thus we can establish a shuttle with only one manned
          spaceship.  The plan needs about 25 years to execute.



          The following table lists the major steps of this plan.  An
     estimate of the cost of each step is given along with an estimate
     of the time needed for its implementation in terms of years after
     the beginning of the project.

          Table 1 -  Mars Shuttle Schedule

        Component                                      Cost      Years
     1. Build LEO refueling stations.                 $100M      0 - 5
     2. Build an Earth-to-Moon EMPL                     $3B      0 - 7
     3. Send one Energia to the Moon                  $800M      3 - 7
     4. Expand the lunar base over several years      $30M/yr.    7 - 15
     5. Build a railroad to the north pole of Moon    $250M      8 - 13
     6. Build an EMPL at the north pole of Moon         $1B     12 - 18
     7. Build the Phobos spaceship                      $1B     16 - 21
     8. Build the Mars spaceship                        $1B     16 - 23
     9. Send the Phobos ship to Phobos                $250M     22 - 23
    10. Manned Mars Mission ( 27 months )             $500M     23 - 26
                                            totals    $8.1B        26


          The following sections explain each of the steps in some
     detail.  A full explanation can be found in my book, "Jobs for
     the 21st Century".


     1. Build LEO refueling stations
          Why?  LEO refueling stations are needed for several important
     reasons.  First, we need them to refuel our Energia on its way to
     the Moon.  Second, the cheap LEO lift capability will make money.
     This is very important because we want the project to contribute
     to its own financing.  How much?  At least $2000 per kilogram for
     whatever we lift.  Third, the refueling stations will be expanded
     (by remote assembly) into space stations.  Why - to make money by
     providing a spectacular sight-seeing attraction, namely the space
     stations.  This will encourage the building of a small fleet of
     space planes.  And fourth, the refueling stations will refuel the
     spaces planes which will also be used to lift our Mars spaceship
     crew to HEO where the spaceship will be waiting.

     1.1 Which lift capability should be used?
          The best choice would be the cheapest technique.  Rockets
     are very expensive, but are themselves much cheaper than the US
     space shuttle.  The following table lists some of the alternatives
     along with their costs.

          Table 2 - LEO lift options
                                                  C O S T S
        Method                              Lift/kg       Facilities
     1. Gerald Bull's superguns              $600            $15M
     2. Hydrogen gas gun                     $100           $500M
     3. EMPL (Roth design)                   $120           $500M
     4. Russian Proton rocket               $2400       $100M/trip
     5. Russian Energia HLLV                $3000       $750M/trip
     6. US Space Shuttle                   $50000         $1B/trip

          The choice we recommend is Gerald Bull's superguns. In 1988
     Gerald Bull signed a contract with Saddam Hussein to build two
     superguns for him within 5 years at a total cost of $25 million.
     The two guns were actually fabricated by a British company called
     Sheffield Forgemasters.  They cost $10 million each and are
     capable of launching small payloads (about 1 metric ton) into
     LEO using rocket boosted projectiles.  Although the cost per
     kilogram of payload is 5 to 6 times the cost of a hydrogen gas
     gun or an EMPL, the cost of building the facilities is dramatically
     lower.

     1.2 How long will it take to develop this capability?
          Two superguns were actually fabricated by early 1990, but
     their current thereabouts are not public knowledge.  Perhaps the
     department of defense has them.  It would be utterly stupid to have
     destroyed the guns. Gerald Bull had not yet completed the design of
     the required rocket assisted projectiles when he was assassinated
     in Brussels in March of 1990.  Three years should be sufficient to
     design the projectiles and assemble the guns.

     1.3 How would the refueling stations work?
          The refueling stations would use solar power to electrolyze
     water into oxygen and hydrogen which would be liquefied and
     collected in insulated tanks.  The superguns would launch water
     (or ice) loaded projectiles which would be guided remotely to
     the refueling stations.  Since the refueling stations would be
     so cheap, we would establish several, perhaps as many as 18 over
     several years.  There would then be sufficient refueling capacity
     in orbit to lift our entire Mars crew (to HEO) at one time.


     2. Build an Earth-to-Moon EMPL
          The second step of the plan is to build an electromagnetic
     projectile launcher (EMPL) which would be capable of throwing
     projectiles all the way to the Moon - finally realizing the
     nineteenth century dream of Jules Verne.
          Many papers have been written about EMPLs and the related
     devices known as mass drivers.  Both devices use a series of
     magnetic fields to accelerate (or decelerate) projectiles to
     extremely high velocities.  Several mass drivers have actually
     been built by Henry Kolm and Gerald O'Neill.  One paper, by Bruce
     Roth, which appeared in Space Manufacturing (V6, pgs 302-9), details
     an EMPL designed to place rocket assisted projectiles in LEO.
     This design could be augmented to launch the projectiles to the Moon
     instead.  The cost would be four to five times Roth's estimate or
     about $2.5 billion.  We estimate that the cost of materials thrown
     to the Moon using this EMPL would be less than $2000 per kilogram,
     exclusive of the cost of the launcher itself.

     2.1 What is the purpose of the Earth-to-Moon EMPL?
          There are several reasons for building the facility.  First,
     it will be used to resupply all future lunar bases.  Projectiles
     loaded with materials from Earth will be thrown into lunar polar
     orbits from which they will be dropped onto the surface of the
     Moon when they pass over the appropriate spot.  Second, it will
     make money by selling the service of placing materials and/or
     experimental equipment on the Moon.  No doubt many governments,
     companies, or universities would like to place research or
     commercial equipment on the Moon.  Third, when assembly of the
     spaceships begins in high Earth orbit (HEO), the Earth-to-Moon
     EMPL could assist by sending materials directly from Earth to
     the assembly point in HEO.


     3. Send one Energia to the Moon
          The third step of the plan calls for the launching of one
     Energia rocket to the Moon.  This will establish the first
     permanent (unmanned) lunar base.  This is clearly a required
     step in the plan (step 2 could be skipped).  Note that the
     Energia could either climb directly to the Moon or could
     refuel in LEO before going on up to the Moon.  In the latter
     case a much larger payload could be placed on the Moon.  We
     recommend the latter even though it will necessitate waiting
     until the LEO refueling capability is established before
     launching the Energia.

     3.1  What should be sent to the Moon?
          We believe the most important facility needed on the Moon
     is a solar array fabrication facility.  This is because nearly
     everything we will wish do to will require electric power to run
     and the nuclear power generator which will be sent on the first
     Energia will only last a few years.  The next most important
     capability will be a small scale general manufacturing facility.
     The following table lists the equipment we plan to place on the
     Moon with the one and only Energia flight.

          Table 3 - Energia cargo manifest

      1. Volatile extraction machine
      2. "Mont" process machine
      3. Aluminum extraction machine
      4. Silicon extraction machine
      5. Solar cell fabrication machine
      6. Nuclear powered electricity generator
      7. Mold making machine
      8. Vapor deposition machine
      9. Communication equipment
     10. Androids (3-5)
     11. Landing guidance equipment
     12. Multi-purpose vehicles (2)
     13. Miscellaneous critical components

          The first 10 items will be required to fabricate and
     assemble the solar cells into vast solar arrays which will
     power our lunar bases.  Items 7 and 8 will provide the small
     scale manufacturing capability.  All assembly will be done
     by the androids.

     3.2 What is the cost and timeframe?
          The Energia is the Russian designed and built heavy lift
     launch vehicle.  It is the world's only existing HLLV.  It takes
     about 3 years to build an Energia.  The total cost of an Energia
     mission is about $650M - $750M.  The other equipment, with the
     exception of the androids, should be relatively easy to build
     and comparatively inexpensive - surely not more that $1M per
     metric ton.
          The development of the androids is a point on which many
     people may disagree with me.  I believe that they can and will
     be developed within the next few years whether or not we go to
     the Moon.  Thus, they will soon become available for our task.
     Androids are major players in this plan.  They will do most of
     the work on the Moon and in space thus greatly reducing the cost
     of the project.  The level of artificial intelligence required
     is far beyond what is available today, but I believe a determined
     effort will be successful in only a few years.


     4. Expand the lunar base over several years
          The first lunar base will become a manufacturing facility
     whose products will be used to build all subsequent facilities.
     We will attempt to use as much lunar material as possible since
     it will be free, whereas everything sent from Earth will cost
     at least $2000 per kilogram or $2M per metric ton (at least 7
     times more if the Earth-to-Moon EMPL is not built).
          All assembly of facilities and equipment will be done by
     androids controlled remotely from three bases on Earth.  These
     bases will be placed approximately 120 degrees apart around the
     Earth.  Possible locations would include Europe or North Africa
     near 10 degrees east longitude, in the western US or Mexico
     around 110 degrees west longitude and in Australia or Russia near
     130 degrees east longitude.  These bases will cost about $30M per
     year to maintain around the clock.
          The components required for step 5 (the lunar polar railroad)
     are rather simple to manufacture.  A small number of androids
     should be able to construct it with a couple of simple machines.
     The additional androids that will be needed will be sent to the
     Moon in pieces where they will be assembled by the androids that are
     already there.  We must greatly increase the number of androids so
     that we will have sufficient labor to manufacture and assemble the
     EMPL and spaceships of steps 6,7, and 8.  This will require either
     doubling the android population each year or simply throwing
     sufficient android parts to the Moon each year to assemble about
     1000 androids.
          Eventually we will be able to provide facilities to house
     human inhabitants.  The Moon is deficient in three of the four
     elements needed to support life on Earth - namely: hydrogen,
     nitrogen, and carbon.  These elements could be thrown to the Moon
     in useful forms such as ammonia, methane, or graphite.


     5. Build a railroad to the north pole of the Moon.
          The key to the whole project is a new spaceship propulsion
     system which will allow us to transport a large spaceship with
     a crew of 1000 to Mars in as little as five weeks.  This propulsion
     system requires a large EMPL located at the north pole of the
     Moon.  Hence the need for a railroad from the first lunar base
     to the north pole.  The railroad will transport materials and
     androids to the north pole to assemble that EMPL (step 6).
          The railroad will of course be electrified and will be
     powered by solar panels manufactured on the Moon.  Only two
     machines will be needed to build the railroad.  One will prepare
     the roadbed and the other will assemble the tracks, ties, and
     overhead solar panels.  The rails must be shaded from the sun
     during the daylight hours to prevent their expansion in the heat.
     The power transmission lines must be superconducting to prevent
     line loss.  Since the lunar temperature is more than 100 degrees
     Celsius below zero (in the shade), this should not be difficult.
          We have allowed five years to build this railroad which we
     estimate will be about 600 miles or 1000 kilometers long.  It
     will be double track made out of iron.  The lunar regolith (soil)
     contains about 12% by weight of iron, so there will be much more
     iron available than we need.  We estimate a total cost of $250
     million or $50 million per year to build the railroad.  The
     railroad should be completed by the 13th year of the project.


     6. Build a large EMPL at the north pole of the Moon
          The lunar polar EMPL is the heart of the new spaceship
     propulsion system.  The EMPL will throw "smart" projectiles
     to the spaceship which will catch them with another EMPL.  The
     spaceship will then throw the projectiles back towards the
     Moon (or more precisely, in the opposite direction to the
     desired direction of motion).
          This propulsion system works by transferring momentum
     from the "smart" projectiles to the spaceship.  The momentum
     is created by accelerating the projectiles through the EMPL.
     The ultimate power source will be a nuclear powered electricity
     generating plant.  It may be a fission power plant or just
     possibly a "cold" fusion plant.  A detailed description of
     the propulsion system can be found in my book, "Jobs for the
     21st Century".
          This EMPL must be capable of throwing 1 metric ton
     projectiles at 20 kilometers per second.  This is necessary
     so that we will be able to accelerate the spaceship to nearly
     20 kilometers per second for the flight to Mars.  At that
     velocity, the trip could take as little as 35 days (depending
     on the departure date).
          Although the final size of the EMPL may be different, the
     following numbers are indicative of what they might be.  It will
     be about 10 kilometers long and will have an internal diameter
     of one meter.  The entire EMPL will be mounted on circular
     tracks which will allow the EMPL to be rotated clockwise
     between each shot to compensate for the counterclockwise motion
     of the Moon around the Earth.  The power required will be about
     2500 megawatts, which will be supplied by a large array of solar
     panels (mounted over the railroad).
          Following the completion of the circular tracks for the
     polar EMPL, the railroad crew will continue building the railroad
     south down the far side of the Moon.  The purpose of this is to
     provide solar power for all of the lunar facilities when the near
     side of the Moon is in darkness, i.e. when the Moon is between
     the Earth and the Sun.  At that time the Sun will be shining on
     the far side of the Moon.
          If everything goes according to plan, assembly of the lunar
     polar EMPL will begin in the 13th year and will take 5 years to
     complete.  After the fifth year, work will continue to increase
     the power capacity in order to increase the ultimate projectile
     velocity. [The reason for this is that the maximum velocity of
     the manned spaceship is about the same as the maximum velocity
     of the projectiles.  So, in order to get to Jupiter or Saturn in a
     reasonable time, say 6 months or less, we must travel much faster
     than on a trip to Mars.  Jupiter is about 9 times as far away as
     Mars. So, if we travel twice as fast, it will still take us 4.5
     times as long to get to Jupiter.  That means that if it takes us
     5 weeks to get to Mars, it will take us 22.5 weeks or 5.2 months
     to reach Jupiter.]


     7. Build the Phobos spaceship
          The Mars mission will actually consist of sending two ships
     to Mars.  The first ship, which will be unmanned, will climb
     slowly to Mars carrying a load of projectiles which will be used
     to stop the manned spaceship when it arrives and to start it up
     again for the return trip. [If our confidence is very high, we
     could send a projectile manufacturing facility to Mars and build
     the projectiles there.  Then we would never need to send another
     support ship.]
          The major parts of the ship will be a 6 kilometer long
     EMPL and a nuclear-powered electricity generating facility. In
     addition, there will be a large cargo of supporting equipment
     for the subsequent manned spaceship.  It remains to be determined
     whether the nuclear power will be a common fission reactor or if
     it will be "cold" fusion.

     7.1 What other cargo will be carried?
          The following list details the items needed to support the
     subsequent manned mission:

          Component                                Number
      1.  Projectiles                           4000 - 5000
      2.  Disassembled human habitats                12
      3.  Disassembled hydroponic gardens            12
      4.  Rocket booster/landers                     12
      5.  Shuttle craft                              12
      6.  Fuel production facilities                 15
      7.  Nuclear power sources                      15
      8.  Androids                                   50
      9.  Communication equipment
     10.  Observation equipment
     11.  Mining equipment
     12.  Projectile manufacturing plant?

          The projectiles will be used to slow down the manned spaceship
     as it approaches Mars.  Since the velocity of the projectiles from
     Phobos will be about 10 kilometers per second and the incoming ship's
     velocity will be nearly 20 kilometers per second, the total relative
     velocity will be nearly 30 kilometers per second.  Thus, fewer
     projectiles will be needed to slow down the ship than will be needed
     to speed up the ship for the trip home.
          The rocket boosters/landers will be used to place 12 sets
     of habitats, hydroponic gardens, power sources, fuel production
     facilities, two or three androids, and some communication and
     observation equipment at 12 different sites on Mars. The androids
     will be responsible for setting up the facilities and getting them
     operational.
          The mining equipment will dig into Phobos to find the ice
     which we believe is buried there.  Some of the fuel production
     equipment will produce oxygen and hydrogen from the ice which will
     be used as rocket fuel to land all the other equipment on Mars.

     7.2 Where will the Phobos ship be built?
          The ship will be assembled in high Earth orbit, actually
     in the same orbit as the Moon, but either 60 degrees ahead of
     the Moon at L4 or 60 degrees behind the Moon at L5.  L4 and L5
     are two stable gravity wells which were first discovered by
     the French mathematician Lagrange.
          Most of the components will be manufactured on the Moon
     and thrown to the assembly point by the polar EMPL.  This will
     save vast amounts of money.  Remotely controlled androids at
     L4 or L5 will assemble the ship.
          We estimate it will require several years to design the
     Phobos ship and equipment.  We have allowed 3 years to assemble
     the ship beginning in about the 18th year of the project, and
     about 1 year to transport the ship to Phobos (year 22 or 23).


     8. Build the Mars manned spaceship
          The Mars spaceship will have three major components; a
     6 kilometer long EMPL, a nuclear-powered electricity generating
     facility, and the crew's quarters.  The entire ship will weigh
     (mass) about 3000 metric tons.  This will include 1900MT for
     the EMPL, 100MT for the 500MW nuclear generator, and 1000MT
     for the crew - one metric ton each.
          Much of the design of the Phobos ship can be employed in
     this ship as well.  The fully assembled crew's quarters will
     be the major new component of the Mars ship.  Quarters will be
     provided for a crew of 1000.

     8.1 Why take such a large crew?
          Of course there are many reasons.  The following list gives
     some of them.

     1. It will transform the first Mars mission into the greatest
        international expedition of all time.
     2. It will cause an exponential increase in public interest
        and political support for the project.
     3. On-board seats can be sold to the public worldwide to raise
        funds to support the project.
     4. The cost per person will be greatly reduced from that which
        would occur if a crew of fewer than 10 were sent on a
        similar mission.
     5. The knowledge and experience to be gained from a large
        crew is clearly much greater than could be accomplished
        with a small crew.
     6. The crew will not be a small elite group selected in some
        obscure and suspicious way by unknown and untouchable
        bureaucrats or governments.
     7. Crew members need not be special in any way (except perhaps
        in not being seriously ill); however, since weight will be
        important, women may have a preference.

     8.2 What will the quarters be like?
          The crew's quarters will be built in the shape of a ring
     which will surround a short segment of the length of the EMPL.
     The ring will be about 200 meters in diameter, 20 meters wide,
     and four floors (12 meters) high.  The top and bottom floors
     will grow food and the middle two floors will house the people.
     The entire ship will rotate about the central axis (the EMPL)
     at about 3 rpm which will create artificial gravity for the crew.
     Thus "up" will be toward the axis of the EMPL.
          Artificial gravity provides many advantages over the
     microgravity environments of all previous human space flights
     - such as:

     1. Normal gravity for the crew during the flight.
     2. No atrophy of the muscles, including the heart.
     3. No blood deterioration
     4. No decalcification of the bones.
     5. No daily exercise programs will be needed.
     6. Common human activities can be accomplished normally.

          Each crew floor will consist of apartments on either side
     of a central hallway.  Each apartment will be about 5 meters
     by 9 meters (3 meters high) and will be shared by two people
     (plus possible minors).   Bathroom facilities will be shared to
     save weight and will be maintained by the androids  - as will
     kitchen, dining, and recreation facilities.
          Crew members will be allowed to design their own apartments.
     For further details please see chapter 9 of my book.

     8.3 What is the cost and timeframe?
          Assembly of the Mars ship should begin at the same time as
     the Phobos ship (the 18th year).  It should be completed by the
     22nd or 23rd year so that the mission can proceed immediately to
     Mars.
          The cost of building either the Phobos or Mars spaceships
     is seriously complicated by three factors which are not encountered
     here on Earth.  First, the materials from the Moon will be free
     except for their extraction and fabrication costs.  Second, the
     power needed to operate all the equipment will also be free (solar
     power).  Third, the cost of assembly by remote controlled androids
     is very difficult to estimate.  It depends very heavily on the
     intelligence of the androids themselves.  If we can provide them
     with sufficient intelligence that they could be nearly self-
     sufficient, then some androids could monitor others and thus
     costs would be greatly reduced.
          We have estimated $1B for each of the spaceships.  If each
     ship takes 4 years to assemble, that corresponds to 2500 humans
     at a salary (including all benefits and taxes) of $100,000 per
     year for each ship.  That is really a lot of labor for such simple
     assembly tasks. [Granted the assembly will be in space, but remember
     that the androids won't need air to breathe, or spacesuits, and
     the cold will not bother them. Furthermore, they can work 24 hours
     a day, seven days a week.]

     9. Send the Phobos ship to Phobos
          As early as possible, the Phobos ship will be sent on a
     Hohmann trajectory to Mars.  This will take about 9 months.
     During this time, assembly of the Mars spaceship will continue
     in HEO.  It will probably require several months to set up all
     the fuel manufacturing facilities on Phobos to produce the fuel
     needed to transport the habitats and other equipment down to the
     surface of Mars (a distance of about 6000 kilometers).  During
     that period, the surface of Mars will be observed closely and
     12 landing sites will be selected in close consultation with
     the crew who will be going to Mars.
          Perhaps a year after arrival at Phobos, the landers will
     be ready to drop down to the surface.  Next, the androids must
     set up habitats, the hydroponic growing equipment, the fuel
     production equipment, and the nuclear power facilities at each
     of the 12 sites.  This will probably take several weeks.  Each
     site must be self-contained and must have its own air and water
     supply sufficient to support its future human inhabitants.
          The fuel production equipment will probably produce fuel
     from the Martian atmosphere by breaking the carbon dioxide (which
     constitutes 95 percent of it) down into oxygen and carbon monoxide.
     There may also be ice under the surface of Mars which could be
     used for fuel.  Whatever fuel we can produce will be used to lift
     the landers back up to Phobos to await the manned spaceship.  This
     operation may take several months if the fuel is produced at a
     low rate.
          The total time between launch windows to Mars is about
     779 days or 25.5 months.  We should have everything ready for
     the manned mission in about 18 months.  Thus, we should have
     a little spare time before the launch of the manned mission.

     10. The first manned mission to Mars
          As mentioned previously, the first manned mission will
     take a crew of 1000.  Interested parties will be able to purchase
     passage on this expedition several years in advance of departure.
     The tickets will cost about $2 million each - clearly not cheap.
     Sale of these tickets will raise $2 billion to help defer costs
     up to this point in time.
          We expect an international group consisting of married
     couples from many different countries and all races.  It may be
     necessary to limit purchases by individuals, companies, or
     countries so that some tickets will be available to individuals
     from countries other than just the developed ones.
          A rough outline of the mission follows:

     1. Lift the crew to LEO using a fleet of space planes such as
        the Spacebus (promoted by David Ashford and Patrick Collins),
        the Space van (Len Cormier's TSTO plan), the Hotol (a British/
        Russian TSTO scheme), or Sanger a German TSTO vehicle.
     2. Refuel the space planes at several LEO refueling stations.
     3. Use the same space planes to lift the crew to HEO and the
        waiting Mars spaceship.
     4. Climb to Mars in 5 weeks using my new propulsion system
        (US patent #5,305,974).
     5. Upon reaching the Mars system, rendezvous with Phobos and
        transfer the crew to Phobos by small shuttle craft.
     6. Using the 12 landers, disburse the crew to the 12 different
        sites on the surface of Mars.
     7. The landers will touch down simultaneously.
     8. The crews will remain on Mars for 2 years - until the
        return launch window.  They will live in the habitats and
        will eat the food grown in the hydroponic gardens.  They will
        explore, experiment, and document their findings for fun,
        profit, and history.
     9. The landers will then lift the crew back up to Phobos - where
        the return trip will simply be the reverse of the outbound
        trip. Total mission time: about 825 days.

     10.1 Financing
          Income from the first manned Mars mission will not only
     pay for itself, but will also cover some of the costs incurred
     previous to the mission.  We have identified four major sources
     of income from this mission.

     1. 1000 tickets at $2 million each will yield $2 billion.
     2. World wide television and radio rights to live broadcasts
        throughout the mission - conservatively $1 billion.
     3. Sales of mission recordings, videos, and data not broadcast
        by the media - $500 million.
     4. Sales of Martian souvenirs - $500 million.

        Total: $4 billion.

         Subsequent missions will cost much less since the two ships
     will already be built; however, we anticipate somewhat less
     income from subsequent missions since they can no longer be
     "the first manned mission to Mars".
         Other sources of income include the inexpensive LEO lift
     capability, the tourist attraction of the LEO space stations,
     the cheap lunar placement capability, the sale of lunar products
     and souvenirs, and other sales of radio and TV rights.

     10.2 The space planes
          When I surveyed the world's space planes for my book, I
     found there were at least 15 different programs around the
     world.  They varied from the US space shuttle and the Russian
     Buran space plane, to US, Japanese, and Russian SSTO (single
     stage to orbit) programs, to various TSTO (two stage to orbit)
     plans as mentioned above.
          Today only about 10 of these programs are still alive, but
     perhaps others have been begun as well.
          It seems clear that the TSTO plans will be the least
     expensive and should eventually become operational.  Projected
     costs are in the neighborhood of $100 per kilogram to lift
     passengers to LEO.  At those rates, tourist tickets to LEO
     could be available for $10,000 - $15,000.  We believe that
     this will foster the growth of a small fleet of space planes
     over a period of several years.  Our timeline would allow
     more than 15 years between the establishment of the first
     LEO refueling station and the departure of the first manned
     Mars mission.  That should be sufficient time to develop the
     needed 10 to 20 space planes.

     Conclusion:
          The mission described above will just be the first of
     many.  Since the primary manned spaceship will not land at
     either Mars or Earth, it can and will be reused.  Thus, we
     have established a Mars shuttle for less than $10 billion.