In Praise of Large Payloads for Space by Joseph Friedlander Part 3: Uploading– Featuring the Aldebaran 2

A guest post by Joseph Friedlander

The “In Praise of Large Payloads for Space” series continues with Part 3: Uploading–
–Featuring the ALDEBARAN 2
Thanks to reader Kai Hiwatari for jogging my elbow to finish this series!

If a simple water tank this ET could hold 2100 tons plus of water. The ALDEBARAN 2 could land 10 of these on the Lunar surface at one go.  If filled with liquid hydrogen/oxygen, (730 tons) it could land over 28 of them on the Moon—but why haul the oxygen? ?  Liquid hydrogen could go to the Moon in a load of nearly 200 such tanks.—or 180 tanks and the 2000 ton condenser plant to keep them liquid indefinitely—And the ALDEBARAN 2 has the internal volume to hold them.

         ET Length: 153.8 ft (46.9 m)
·            Diameter: 27.6 ft (8.4 m)
·           Empty Weight: 58,500 lb (26,500 kg)

·           Gross Liftoff Weight: 1,680,000 lb (760,000 kg)

ALDEBARAN  (Cole, 1960)

 The ALDEBARAN 2 can launch more in one mission than ever orbited by all 135 shuttle missions—including the orbiters and ETs themselves, not just the payloads. And do it again next month.
The United States has spent $196 billion on the space shuttle . Wouldn’t the ALDEBARAN 2 have been a better investment? A total of 355 people from 16 countries occupied 852 mission slots on the STS (Space Transportation System). Less than 600 people have EVER been to space in a half century of trying. In an all out evacuation mode the ALDEBARAN 2 could probably shuttle 50,000 people PER SORTIE to a waiting moonbase in case of planetary emergency.  A fleet of 300, flying once a month, could evacuate 180,000,000 people in a year—the population of the USA in 1960.
What is the point of such exuberant scale? Throughput to grow a vast space based civilization—and the ability to amortize staggering expenses.  Every million dollar fee/expense amortized over 10 tons is $100 a kilo. (Rather discouraging to those trying to reduce the cost to orbit under $100 a kilo only to have a launch fee added!) Amortized over 1000 tons is $1 a kilogram surcharge– But if you have 30,000 net ton to orbit shuttle, a million dollar expense is 3 cents a kilo!  


This article will finish the survey of launch systems, combine Dandridge Cole’s Ca. 1960 ideas (ALDEBARAN design in various publications) and Anthony Tate’s baseline engine design (Liberty Ship at the dead website to make a composite craft called the ALDEBARAN 2 for purposes of ‘what if’ scenarios. 

Final Listing of Our Incomplete Large Space System Survey

A few more craft referenced should complete our preliminary (not thorough) survey of early 60’s massive spaceship ideas.  For definitive and massive data on them the best reasonably priced references are in the back issues of Aerospace Projects Review here
And for free there is the wonderful Atomic Rockets website by Winchell Chung here
A nicely inclusive though not necessarily comprehensive source for all kinds of space launch systems is here
And here is a wonderful resource

by Marcus Lindroos 

And of course you can spend all day on the wonderful memory evoking site.
 Take note of the Nexus and Super Nexus,
That’s an early Saturn V at left for scale.
 being a leaky open cycle gas core system, I don’t believe they bring much value to the table—I am going to get enormous doubt from the readers for venturing to predict that closed cycle gas core reactors will be flown ever—but open cycle ones that leak fissioning U-235 would possibly be even more unpopular than nuclear explosions themselves.
I am analyzing why I am getting that reading and basically people have an idea (true in solid core reactors and their holding pools but not in constantly cleaned molten salt and gas core reactors) that enormous amounts of waste are present wherever a reactor is. Leaky flying reactor does not sound too good, especially if it’s designed that way. Makes the designer look cold-blooded, kinda. Thus I am not hot on open cycle gas core reactors.   It is not logical but very little of feeling and emotion is based on logic, it is the human environment we operate in and we have to get used to the reactions.  If a closed cycle engine (new load, no old waste) goes leaky (not boom) by accident once every year (1 failure in 90000 engines over 4 engine-hours each or 1 failure per 360000 flight hours  and dumps 235 in the ocean, that is sad—but uranium in the ocean is a 3 billion ton fact of nature, another 50-80 kilos won’t bring “The Death of The Oceans ™)
  • Nexus class ships with closed cycle engines could lift Sea Dragon class payloads (500 tons) to lunar orbit, not Earth orbit.
  • Dumbo also was a NERVA like solid core nuclear engine that could take off from Earth’s surface. (Unlike NERVA, best considered as riding atop a Saturn V) Solid core but innovative geometry, no chemical booster stage. With a massive scale up it could list thousands of tons with 8-11 km sec exhaust velocity using hydrogen propellant. One can imagine the early versions of ALDEBARAN powered by variants, but at huge cost in lost payload.
  • PDF on Dumbo from Los Alamos via Dunnspace  NICE heat exchange geometry done with primitive equipment in 1957!
  • Also note NBF’s Wang Bullet concept under the name Verne Gun on the Atomic Rockets site.
We have already covered Orion, Super-Orion, and other explosion based systems for achieving high exhaust velocities with energized reaction mass. 
One more system not mentioned yet or indeed anywhere else except in a rocketry book for young people I saw once – is the SCHMOO (named after the Al Capp cartoon character that was big around 1948  and presumably is bulbous and voluminous like that character. I saw one reference in an early 60’s publication for children and have found nothing on the Internet about the SCHMOO but it seems to be one of a family of theoretical spaceship designs that used allegedly contained nuclear explosions. As in, inside the ship nuclear explosions (yes, they left the nozzle, that was the idea).  
 There were a few other INTERNALINTERNAL nuclear explosion designs (implying a small bomb, a large ship, an unfortunate flight crew, or all of the above) with other names, often a huge steel sphere with an arrowhead top propelled by 10-100 ton blasts–the expression put a Tiger in your tank doesn’t quite seem to cover that.
 The most complete account of two of these systems areis covered ably by Scott Lowther in his Up Ship blog. –another project by Dandridge Cole while Orion was still deeply classified, at the private Martin company (Titan I and II missiles) in Denver.  The formula is 10 tons TNT equivalent (2400 energy capsules for only $10,000 1960 dollars each)  + 858 pounds of water equals specific impulse of 931 seconds. That is the Model I design. Model II uses hydrogen for 1150 seconds impulse and 5800 individual $10,000 energy capsules per launch (an open market for which I am sure would please the Dept. of Homeland Security no end 🙂 A ten times larger Model IIa used 100 ton blasts and got 1350 seconds impulse.

If I am reading Lowther correctly the general concept was examined by Livermore Labs in 1963 and named Project Helios. This should not be confused with the similarly named Kraft Ehricke Project Helios that used the Atlas Missile booster/sustainer architecture to use a conventional booster and a nuclear sustainer for conventional space launch.  That Ehricke work is referenced here Livermore Project Helios may be the source of that arrowhead artwork I ran across; the timing of the book and publication dates in my library make it likely.
Lowther also covers a nuclear pulse jet design in passing (Thrust under 2 Saturn Vs worth so hardly worth mentioning in this article) and comments on the ALDEBARAN design, but without a lot of detail there. “In 1959, Dandridge Cole envisioned craft such as this being the backbone of the space launch industry in the 1980-1990 timeframe. The ALDEBARAN was to be able to carry 60,000,000 pounds of payload into low Earth orbit, or soft-land 45,000,000 pounds on the Moon. Scale is shown by comparing the ALDEBARAN to the liner SS. United States; the helicopter shown loading cargo into the ALDEBARAN also helps show the substantial size envisioned. Clearly, if the vehicle could carry 60 million pounds of payload, it would need a bigger payload loading door than the one shown. Curiously, a secondary cockpit or observation deck is shown on the vertical fin”.
 The survey continues with Paul Birch.
 Anyone who has not investigated the works of Paul Birch is in for a treat. I was saddened to learn of his passing in 2012 when compiling this post. His Wiki Bio
His website lapsed but has a mirror for his amazing tech articles which tend to be less about simple ship designs and more about enabling world girdling civilizational breakouts into space.  Look for the technical PDFs at–
Rounding out the large booster idea survey we come to the wonderful flying machines of the great Phillip Bono 

That’s Phil Bono near the ROMBUS model at upper left.

Phil Bono Spacecraft  Patent assigned to NASA–downloadable PDF there

a SSTO family tree chart relevant to the Phil Bono spaceships mentioned below–

A non nuclear heavy lift idea in the Sea Dragon class (~500 tons up) — the ROMBUS/Ithacus, Sr–a design by Phil Bono
A $125 model kit of the Ithacus launcher
The Douglas Ithacus Senior. might have been another superheavy lifter, (450 tons, the mass of my local 25 x 15 meter (450 cubic meter) swimming pool to orbit—such an orbital tanker could have refueled a lunar lander in Earth orbit to carry perhaps 100 tons net cargo to the lunar surface—vs 18 tons for a Saturn V.) capable of a takeoff at 6400 tons with 450 tons or so delivered to 185 km LEO. 
Or to invade a country a quarter way around the world within half an hour with 1200 troops and light gear.

Ithacus’ 1966 study had art showing 1200 rocket-belt equipped scout troops driving Jeeps off the rocket in what looks like Southern Africa
—after say a 25-35 minute flight from the States—
  I am trying to imagine a repeat of D-Day (160,000 troops) with  134 of these suckers launching simultaneously—but the problem is not starting that war but finishing it—even assuming the enemy has no ABMs, the follow up logistics to a continental size invasion are insane if you actually intend conducting it by rocket.  (At VE Day I think there were 2.5 million US troops in Europe, -2083 rockets worth–supported by 5,300 ships of various sizes and 50,000 vehicles and 11,000 planes.) There is also the non-trivial problem of retrieving the vulnerable ‘empties’ without getting them strafed by the enemy. If you intend seizing a beachhead by rocket and have command of the sea to feed that beachhead—that is another story but in that case why bother with rockets instead of cheaper airplanes? Against a smaller than continental size enemy it might work but what a gamble that would be.
Another more peaceful use of Phil Bono’s single stage to orbit vehicles: New York to Bombay in flight travel time gone down “from 22 hours to only 40 minutes”. Not merely a SST, not a hypersonic transport but a fractional orbit transport. Any city from any direction, only 45 minutes away.
$125 Fantastic Plastic Model of the Ithacus, Sr.

And amazingly, Phil Bono imagined using the Rombus/Ithacus Sr. and related vehicles to make a 1000 man moon base (tour of duty, only 4 months!) in the so called Project Selena }

And amazingly, Phil Bono imagined using the Rombus/Ithacus Sr. and related vehicles to make a 1000 man moon base (tour of duty, only 4 months!) in the so called Project Selena involving massive lunar landing logistics to make a moon base whose goal was to—launch a mission for Mars!  

In other words to build a Cape Canaveral at the Moonbase and use it for Martian launches. 

Alternate from Earth Orbit ROMBUS/Ithacus family Martian mission logistics
The courage shown by those early designers is staggering compared to today’s play it safe worldview.  
Bono’s Project Selena called for the establishment of a 1000-man lunar colony in four successive phases by 1984. The main purpose of the Selena base was to support three unmanned Mars cargo delivery missions by 1986 and about half of the payloads (16,029t by mass) would be dedicated to the “Deimos” Mars follow-on. The total mass of the lunar cargo was a staggering 32,950 metric tons, requiring 1341 ROMBUS launches and 1011 cargo/propellant transfer operations in low Earth orbit over 8.5 years. A fleet of 10-15 ROMBUS vehicles would have to perform 330 lunar landing missions to deliver the crews, cargo and propellant. Bono lists the following design assumptions for Project Selena:

# 40-flight average ROMBUS lifetime.
# Personnel delivered to Moon at 90.7kg/man
# Life support requirement of 4,536g/man/day
# Maximum lunar tour of duty of 4 months
# Lunar refueling base will store liquid oxygen and hydrogen propellants for Mars mission
# Cryogenic propellant stored in cylindrical tanks at permanently shadowed location on Moon
# Reusable Moon-Mars orbit-Earth vehicle lands 21,772kg on Mars (18,143kg useful payload) and consumes 5,343t of propellants per trip. The fourth, manned, Project Deimos mission then departs from Earth orbit in 1986.
Notice that the total landed mass on the lunar surface was a mere, not a staggering, 32,950 metric tons, under 2 ALDEBARAN landing missions, (Not 1341 launches) and you will understand why the existence of ALDEBARAN would revolutionize space logistics.  But so impoverished are we compared to the lost future of 1986 as projected in 1963, that even the Ithacus, Sr. and ROMBUS is science fiction like in capability. 
A modern superheavy plane capable of nearly that class of load is the An-225
Fuel capacity: 300000 kg
Cargo hold – volume 1,300m3, length 43.35m, width 6.4m, height 4.4m
range with maximum payload: 4,000 km (2,500 mi)
Crew: 6
Length: 84 m (275 ft 7 in)
Wingspan: 88.4 m (290 ft 0 in)
Height: 18.1 m (59 ft 5 in)
1300 cubic meters fuel capacity, just for comparison the town where I live has a 25 x 15 meter pool that holds 450 cubic meters or tons of water so you are talking 3 swimming pools worth of fuel to fly 250 tons 4000 kilometers.
On 11 September 2001, carrying 4 main battle tanks[6] at a record load of 253.82 tonnes (279.79 short tons) of cargo,[5] the An-225 flew at an altitude of up to 10,750 m (35,270 ft)[32] over a closed circuit of 1,000 km (620 mi) at a speed of 763.2 km/h (474.2 mph)

The shipping cost on this vehicle seems to be well over a dollar a pound or $2.20 a kilo.
 Now here is the question for people saying how heavy lift rockets are too big for an economical flight model already.  EXPENSIVE big lift rockets, of course. There is such a thing as pricing yourself out of a market, and the Saturn V and Energiya did it.  But suppose there were super-cheap big lift rockets.  Use the analogy of the 747—which can carry even in early models (1970 or so) 55 tons cargo, and nowadays in the heavy cargo version over 120 tons—the payload of the Saturn V, significantly—if the 747 is already too big why does the AN-225 have a market to the extent of being booked up?  The answer is, there is always an outlier cargo. Some cargoes are so big it never occurs to anyone to send them by air until the possibility exists.  Whether you could make a living while the market developed is a different question.
For example, if there was a way to send 20,000 tons by air at $3 a kilo to some remote site —and that is a transport fee of $180 million dollars)— (Say a new nuclear powered South Pole base in one whack, pretested) someone would do it sooner or later.  The trigger point might be for example, the difficulty and danger of relying on integrating a nuclear base under Antarctic conditions—it might actually be cheaper to ship it pretested and pre-crewed and then evacuate the crew by plane at end of life. (The analogy to a working nuclear lunar base is obvious—The ALDEBARAN 2 drops off the lunar base in the middle say of the lunar night with the reactor working already, pre-manned, with the first crew with 25 years of food rations).  Suppose the Soviet Union of an alternate timeline had done so in 1988, and then the Soviet Union fell. Most people don’t know of the Russian Ice Station program  but an exact analogy presents itself—look at the dates between these two stations
October 22, 1988
July 25, 1991
April 25, 2003
March 6, 2004
The Soviet Union collapsed and Russia did not resume the program for 12 years during the post-collapse situation.  Now in this case there was pickup of the crew but if not, that would have been a bad way to go. Think of a lunar analogy to this—you want YEARS of rations prepaid for,  and in place under your physical control and your salary in escrow with a reliable third party BEFORE you go up for a tour of duty just in case something happens. With the ALDEBARAN 2, such mission robustness exists. Without it the baseline plan is to die begging on You Tube for help from Earth that never comes.
This article will now combine Dandridge Cole’s Ca. 1960 ideas (ALDEBARAN design in various publications) and Anthony Tate’s baseline engine design (Liberty Ship at the dead website to make a composite craft called the ALDEBARAN 2 for purposes of ‘what if’ scenarios.
Why the redesign? Because the original ALDEBARAN design was conceptual at best. It was designed to indicate the size of possible ships in the 1980-90 time frame HAD TECHNICAL PROGRESS CONTINUED AT THE BREAKNECK 1945-64 PACE for another 25-35 years. (To illustrate the pace of change back then, remember that the first Mach 2 plane flew in 1953 and in 1963 there were thousands of deployed Mach 2 fighters. In 1945 an atom bomb weighed 5 tons and there were a handful of them, in 1964 there were thousands of nuclear artillery shells that a strong man could heft, etc.)
   The original ALDEBARAN design could have used a wide variety of engines. Indeed the path to ALDEBARAN would start with 50,000 ton chemical boosters, then solid core, then eventually gas core. Each time upping the payload and dropping the reaction mass.  We need hard numbers to work with and that means a detailed conceptual design.
A dream of the late 50s and early 60s, shared by visionaries now passed on, such as Dandridge Cole  ( and Maxwell Hunter, were exhaust velocities on the order of 15-30 km second (achieved using common reaction mass like water, liquid hydrogen, ammonia, methane etc energized by gas-core nuclear reactors) making possible the kind of rocket performance that was featured in the movie 2001: A Space Odyssey.  (And which was in fact the informed opinion of some of the best technical experts of the time.)
 For example, 13.8 kilometer a second delta-v (velocity change increment) to reach the Moon in around 24 hours using the fictional ARIES I-B and return in another 24 hours to a low-Earth orbit space station.  Arthur C. Clarke wrote of a 12 kilometer a second (over the minimum 11.2 km/sec) trajectory that could impact on the Moon in 19 hours.
Building such gas core nuclear reactor (GCNR) engines is not a trivial (nor an impossible) thing.  But the engineering challenges center around one fact:  To achieve exhaust velocities by thermal means you need extreme temperatures, and to fly with such an engine it must be light enough to be accelerated and to make the whole operation economical in a mission planning sense. Indeed a 1968 NASA GCNR study they assumed a thrust to weight ratio just one tenth the Liberty Ship website assumptions.
See the coverage in Winchell Chung’s Project Rho Atomic Rockets website
In summary, a high thrust to weight ratio is needed to take off from Earth’s surface with sufficient acceleration, fuel carriage and payload; in theory this is achievable.  The 1968 NASA design was cautious (A trait I would strongly recommend when working with your first gas core reactors. But eventually if it’s going to fly you have to up the thrust to weight ratio. If it’s never going to fly, however, you can get tenure for doing the same cautious work for generations, which basically is what has happened. ) 
In 1968 had you mentioned to someone in NASA working on nuclear fission gas-core engines that what the future NASA would be working on in 45 years would not be a starship but a politically rigged chemical space launch system replacing the Saturn V class lift vehicle retired in December 1972 by –wait for it—August 2032–60 years later, (as in Wright Flyer to B-70, 60 years later!) with no gigantic increase in reliability, cheapness or capacity you might have met with stunned disbelief.  And no, they still don’t get rid of the segmented boosters, O-rings, or politically favored contractors. Look at the last table entry at the bottom at this link to confirm the latest changes to that 2032 date. 
Another 1972 capability recreated at vaster expense than original after 50 years— Skylab II (had Skylab I been a wet workshop it also could have been sent to a Lagrange orbit, not just LEO.
Gary Hudson’s take on why NASA is change resistant The customer specifies, usually in great detail, the bounds of a solution for a particular engineering problem. Contractors ignore such boundaries at their extreme risk. This stimulus/response conditioning of the contractors effectively suppresses any desire to “stand out from the crowd”, except in the most trivial of ways. Governments are by nature conservative entities. It usually does not pay to propose risky endeavors, when safer, albeit more expensive or less optimal, paths may be traveled. The paymasters of government agencies are not technically learned, so they cannot exert effective oversight With a charter to seek out new technology, it is natural to suppose that all new ideas would receive fair and objective hearings from NASA analysts. As most anyone who has ever suggested a new idea to a NASA center can attest however, such is rarely the case. It is in NASA’s interest to take very small steps toward an ill-defined goal since such a policy can sustain the agency indefinitely. It must be remembered that NASA opposed Kennedy’s plan to go to the moon on a crash basis
*For example, reducing the manpower associated with launches may conflict with the goal of providing high levels of employment in key Congressional districts.
Furthermore, it is easy to find justifications for resistance to change on technical grounds, especially in expensive and risky projects such as launch vehicle development. Any junior engineer can show that it is “easier” to build a two-stage vehicle than a single-stage. In the face of clear incentives not to take risks building a vehicle which offers future payoffs which might not be desirable anyway*, it is easy to see that SSTO, along with many other examples of high risk/high payoff technologies, was not likely to be fostered at NASA.
There is a nice discussion of the problems of gas core reactors here–
5000-7000 s should be achieved, this corresponds to temperature of 50,000-100,000 Kelvin
specific impulses of 3,000–5,000 s (30 to 50 kN·s/kg, effective exhaust velocities 30 to 50 km/s) and thrust which is enough for relatively fast interplanetary travel. Heat transfer to the working fluid (propellant) is by thermal radiation, mostly in the ultraviolet, given off by the fission gas at a working temperature of around 25,000 °C.
Jerry Pournelle, in his book A Step Farther Out (1979, Ace Books) posted the following table: Note it assumes you are exhausting liquid hydrogen (a most inconvenient fuel in terms of handling characteristics, but the lightest conventional matter exhaust possible when plasmified into atoms, and thus the fleetest—)
Pournelle p. 213
Engine Temps & ISP (Specific impulse) (Assumes liquid H2)
                                       50%        70%
                                      Ship fuel  Ship wt.
Particle     Exhaust        Specific   Dv        Fuel. DV
ENERGY       Velocity       Impulse   Possible   Possible
in Degrees   of Propellant  Seconds   Mass       Mass
Kelvin       cm/sec                               Ratio=2   Ratio =5
  1,000 K     4.07 x 10E5     415              2.8       6.6
  5,000 K     9.55 x 10E5     975              6.6      15.4
 10,000 K     1.29 x 10E6    1310            8.9      20.8
 50,000 K     2.88 x 10E6    2950           19.9      46.4
100,000 K     4.07 x 10E6    4150          28.2      65.7
1 million K   1.29 x 10E7   13,100          89.0     208
5 million K   2.88 x 10E7   29,500         199       464

So around 50000K is the energy range of interest for us– 2950 seconds impulse with hydrogen.
Note that in the above Pournelle quote we energize liquid hydrogen to 13 to 29 to 41 kilometers a second exhaust velocity, gives us about ten times the current exhaust velocities of –in order—
·           simple buildable amateur rockets (1.3 km/s),
·           professionally made solid boosters, (2.9km/s),
·           and the hydrogen-oxygen liquid fuel engines of space superpowers, (~4.1 km/s),   respectively. 
About double that temperature is needed if water is the propellant.
The ratio of exhaust velocities appears to be, 1 for liquid hydrogen, .78 for methane (CH4) .63 for ammonia (NH3) .5 for water, .4 for CO2, .32 for N2 or CO. This is a rough calculation, not from a published reference.
Rough confirmation from another source:

Cheap and simple water is comfortably dense,and delivers about half the V_e of H2 for a given temperature. And look at that! Half the V_e (15km/s) is exactly what we need!

The exhaust wants to be very massive, very hot and very light in molecular weight—ideally hydrogen plasma. At 2500K hydrogen exhaust exceeds earth orbital velocity, 4000 K  exhaust velocity of hydrogen exceeds  earth escape velocity
Liquid hydrogen is expensive, in mass quantities of the kind needed here it would probably be around $7000 a ton given amortization.   That would be $735,000,000 a maximum ALDEBARAN load. Vs. 50c a ton for water if fresh water. ($52,500) You can see why I like using water for reaction mass.
In reality, rather than use liquid hydrogen we would probably use water (even a million tons can be obtained cheaply and stored long-term). Liquid methane or ammonia possibly with chemicals and organics mixed in for absorption-line purposes. Some mix both pumpable and logistically friendly. We would obtain a lower exhaust velocity for the same energy,  (probably get the equivalent of only about two thirds to one third of the specific impulse of hydrogen) but you cannot obtain more than a few thousand tons of liquid hydrogen simultaneously in today’s market without heroic logistics including subsidizing new plants and storage facilities. (look up the ortho and para states and the need to convert ortho to para If orthohydrogen is not removed from liquid hydrogen, the heat released during its decay can boil off as much as 50% of the original liquid.)  Water is available by simply turning a valve.
On the other hand, U-235 ain’t free either, it costs energy to heat water. If it’s $50,000 a kilogram for U-235 and you pop 300 kilos a shot, you are talking $15 million to heat the propellant. Suppose you need 16 times the heat for water as liquid hydrogen that is 240 million dollars vs 735. And the logistics are a lot easier.

On the other other hand—when you are just getting the ALDEBARAN going you will probably have a learning curve of lower to higher exhaust velocities such as 8 km/sec 11km/sec and 15 km/sec in place of 20  km/sec and 30 km/sec so very tricky to handle liquid hydrogen may tempt designers early on—and much later on, if we ever try to reach a good fraction of the speed of light.
 Confirming that last comment, the early ALDEBARAN ‘started off’ in Cole’s projections with less performance.  But as the defunct Liberty ship site pointed out half the joy of 30 km/sec is the ability to centrifuge your nuclear waste (separating it out and concentrating it)  and retro it directly to the Sun from Earth orbit  –the exhaust velocity, if vectored correctly, is high enough to retro the gas and any waste entrained therein into a solar infall trajectory. Details here:

the exhaust of this nuclear spaceship shoots out at a whopping fast 30 kilometers per second. If you add this 30 kilometers per second to the 8.5 kilometers per second the whole rocket is moving while in orbit, and you point your rocket in just the right direction, you can literally shoot the exhaust right away from the planet so fast that it never comes back. You can then aim it to drop into the Sun without too much trouble. 
Link on calculation of specific impulse.

These exhaust velocities allow science fiction like performance, but you would need equally science fictional materials to build such reusable engines, because no regular nozzle thin enough to fly can contain gas this hot—but there may be ways around this trap.
  • Boundary layer and opacity tricks
  • Sacrificial layers
  • Condensed nuclear matter insulation.
(Note that I do not claim that that last is likely, merely saying that if it existed it would be awfully convenient.  With gram amounts of AB-Matter spread thinly in a radiation barrier, for example, engineering a 5 million K gas core engine capable of 6-month trips to Pluto would be almost certainly possible within a decade. Without it, good luck. 150000-300000 K would be a good temperature range to accelerate dense propellants (not liquid hydrogen) to 30 km/s+ exhaust velocities if it could be achieved.
AB Matter links–
Whatever the trick used to make a working gas core engine—and I have to gloss over this key difficulty because of article length considerations (a book would not be too long to list the difficulties—indeed we easily could get working fusion drives before perfect gas core drives—and you really don’t want to fly with a far-less- than-perfect gas core drive)—let us assume it can be solved.
In the first installment of this series that surveys the extreme heavy lift field
 we introduced the ALDEBARAN, conceived by Dandridge Cole, around 1960, as a 1980 (!)-1990-era space freighter capable of:
60 million pounds (30000 tons to LEO or 45 million pounds 22,500 tons to lunar surface)
3000 isp (specific impulse) 29419.9 m/sec gas core reactor exhaust velocity
Could also be 22500 tons to a Near Earth Asteroid, (at the day of closest encounter) since many of them have less delta-v than the 6-6.3 kilometers per second from Low Earth orbit to the Moon’s surface and the surface of Mars.
In other words, the ability to unload an entire prechecked, pre-crewed, pre-stocked and provisioned industrial plant –not specially engineered for weight reduction–complete with crew and years to decades of supplies at a (nearby) offworld location. Exactly what has NOT been tried yet in the 60 years of trying to fly small loads more cheaply and assemble them in space with astronaut time that has not gotten much cheaper than $100,000 a man-hour.
In the second installment We discussed the uses of private space stations costing say $5- $15 million or less that are functionally the equivalent of the $100,000 million International Space Station  (not all the fancy one of a kind equipment, for sure, since nearly all that cost is engineering and custom labor of some kind of another, plus huge overhead).  But something of say 3x-6x the mass, same cubic, (~850 m3) same functionality but in cruder ways (vacuum proofed marine yard construction welded commercially) and all in one go. A company no bigger than Space-X is now could have their own space station, not a coalition of nations.
 If 2000 tons for such a crude station, in low Earth orbit (half water reaction mass) the ALDEBARAN 2 could drop of 15 of them per sortie. Like smallsats today. Cost for transport, if $5 a kilogram, would be  $10 million. The station itself should be buildable for $5 million.
 The first ones should be very crude but there would be a learning curve of progress. For an analog, see the Mars 500 facility— or Sealab

Or submarine construction as an analogy to pacecraft with no weight limitation–The Submariners 1967 (Nuclear attack sub)
In summary (go to to see the full treatment) it is astonishing that after nearly 60 years of the Space Age we still have not done various amazingly simple experiments because experimenters are weight limited and no one wanted to risk a one of a kind ‘national asset’ on even marginally risky experiments such as:
  • A cutting frame and furnace to melt down upper stages and try metal shop tricks with the obtained metal. Like making sheet metal. Like density separation of alloys and then distilling to pure metals and making new alloy combinations.  In vacuum and microgravity. Have to be tried someday, why not now? Then ion tug experiments or solar sail loom experiments to bring some of the 5000 tons of space junk to the furnace. Building the experience base in space salvage and amassing a stockpile of mass in orbit.
  • (Homesteading tanks and other space junk. Experiments in same. One reason they have not done this is the extreme cost of low orbital maintenance at today’s prices. Another way of saying, prices going lower will enable all kinds of things not tried yet in orbit.  This and operational concerns were reasons they never retrieved ONE of the 135 space shuttle missions’ external tank, let alone the approximately 3000 tons of them they could have orbited. They did not regard it as amassing wealth in orbit but as taking unnecessary risk.  Enough space to house 30,000 people in space—but of course if you can hardly support an 8 man space station with a 20 ton capacity shuttle you are not going to be taking any extra burdens on.)
  • A workshop using vacuum deposit 3d printing to try to rebuild upper stage engines for reuse in space. (My nominee for the Space-X stationJ)
  • The behavior of matter under extreme evaporation in vacuum. Opacity studies of great interest to say developing of Gas-Core Nuclear Reactor engines, explosive driven designs, and more.
  • A centrifuge like this cancelled one
 to ACTUALLY FIND OUT IF MARTIAN OR LUNAR OR ASTEROIDAL GRAVITY WORKS FOR PEOPLE or kills them (say, through auto-immune deficiency effects as some have suggested).  Or, as Heinlein has suggested, prevents them from coming back to Earth. Or is say Lunar gravity just enough to keep you return-capable, but say asteroidal gravity not?  Or is even a thousandth normal gravity enough to provide some inner cue to the system that microgravity does not? 
Yes, a centrifuge module would have been a weighty module but literally half of the station could have been designed this way.  (Oh, I forgot, the complications that rotating joint might introduce might endanger a ‘national asset.’) This lack of space centrifuge testing is an amazing omission when one reads the official goals of the space bureaucracies to explore the cosmos. (And presumably keeping humans healthy when doing so.)  It is not so amazing when you consider that their real, this year, goal is to keep their appropriation at least what it was last year. Everything else can be postponed, and has been, for half a century.
 If we KNEW we could live in Martian gravity (.38 of Earth) we could also settle Mercury (.35) —and if we could live in Lunar, gravity (.16) we could also settle the major moons of Jupiter and Saturn (if we could get to them safely). If we could live in asteroidal gravity (say 1-4%) many more small bodies would be safe to live on. Radiation shielding would be as simple as digging a maze of tunnels.  KNOWING this in advance could cut decades off a colonization timetable—but since they have no real intentions in that regard, no sweat off their nose.  But still, KNOWING it was safe would, one thinks, make the ethical burden of sending astronauts to Mars a lot lighter. It would still be dangerous, but one unknown removed from the equation can make an equation solvable.
A general discussion of the problem is here
Prototype farm module pdf for the ISS
  • A ceramics workshop for making and annealing behind a mylar sunshade structural shapes of lunar basalt. Then testing by retroing, for example, reentry designs made of lunar basalt.  You think that might be important to a settlement on the Moon that wants to sustain itself through exports to Earth someday? Pretested designs are cool things to have.
  • Don Petit’s spare-time experiments  in one DVD quality video

that probed the actual behavior of water and other substances in space.  This is very basic stuff that is the essence of spontaneous scientific curiosity—and yet he had to do it on his own time.  (He made no major new scientific discoveries but did some things that probably were never done that exact way before)  With hundreds of stations, and thousands to tens of thousands of experiments, there would be incredible discoveries. Some very practical. Shaped water could be frozen and used for depositation molds at low temperatures. Who knows what else.
An intelligent group of high school shop students who are also space geeks could make up a list pages long of stuff to try; heck, a comments page that was FOLLOWED by an intelligent and empowered moderator on the scheduling staff could make a good list of experiments to try, but with a ‘priceless national resource’ any such enthusiast suggestions will line up centuries behind impeccably arcane ‘peer-reviewed’ studies that really make no difference because any results are not going to be followed up anyway.
 The decay state of a space bureaucracy (not the vigorous youth that everyone remembers) is that everyone important gets a place in line, once, and half of the proposed experiments might actually fly after years of whittling down the dream and shoehorning more researchers onto a paper that already has thirty co-authors. The idea of rapid nimble follow up studies is a sick joke in such an academic/bureaucratic mill. 
But with hundreds of private stations, any reasonably good idea might be able to get a hearing, and more importantly a trial. And hundreds and then thousands of space productivity tricks would be learned that would make first possible and then practical economically self-sustaining space settlement.
The key, of course, is hugely less cost to orbit than now.  Not $5,000 a kilo but something more like $5 a kilo.
Now I am going to construct my own model of the ALDEBARAN, which I dub the ALDEBARAN 2, based on the data from both Dandridge Cole and Anthony Tate’s former Liberty Ship Website.
  • My model of the ALDEBARAN 2
  • Up to .7 propellant fraction (many missions don’t require fill up)
  • 22.5 kt landed on moon, 30 kt  to low earth orbit, (Notice the huge difference between  the .75 ratio between lunar landing and LEO boost and say the 8:1 ratio with conventional propellants)
  • say 15 kt structure (10 kt is possible)
  • Maximum propellent load  105 kt
  • 45 maximum non-propellant load
  • maximum takeoff weight 150 KT probable thrust  up to 180 kilotons (throttlable)
  • 180 million kg thrust
  • Ship Cost, est., $22.5 billion each
Cole’s design had one huge engine. Tate’s design had 7 engines for emergency safety shutdown (and to enable flushing nuclear waste to solar infall velocity)
and for redundancy. The ALDEBARAN 2 has 300 gas core reactor engines, shielded against accidents in neighbor engines like in the Space X designs, which if oriented correctly will make lunar landings much more plausible than 1 huge engine.  You don’t really need 300, I just did that to work with the Liberty Ship engine specs–
  • Liberty Ship engine specs-
  • 60 tons each mass
  • thrust to weight ratio 10:1 Note: NASA 1968 study engine only yielded a little over 1 to 1
  • 600 tons thrust each
  • Thermal output of approximately 80 gigawatts.
  • 25,000C exhaust temperature. 
  • addition and removal of fuel “on the fly.” 
  • Closed cycle (contained fissionables)
  • exhaust velocity of 30,000 meters per second, Isp of 3060 seconds.
  • three pumps move 178 kilos of liquid hydrogen per second combined
  • Guess 50-80 kilograms of U-235 per engine
  • 0.9664 gram U235 second burned (needs full critical mass to function) derived from Atomic Rockets website  table below
1000 MW burn
202.5 MeV
83.14 TJ/kg
0.01208 gram/sec
197.9 MeV
81.95 TJ/kg
0.01220 gram/sec
207.1 MeV
83.61 TJ/kg
0.01196 gram/sec
Now for the ALDEBARAN 2 we need 300 of these engines.
·        60 tons each – 18000 tons of GCNR engines
·        ~300 grams second U-235 consumption (4.8 Kilotons TNT equivalent per second) so if 1000 seconds boost 300 kg U-235 fissioned (4800 KT TNT equivalent per flight)
·        Guess 50-80 kilograms of U-235 per engine so 15-24 tons U-235 needed per ship. If $50,000 a kilogram for U-235 , $50 million a ton, fuel loading is $700-$1200 million per ship. Ship Cost, est, $22.5 billion each, so initial fuel loading is ~ 5% cost. Flight U-235 cost (300 kg—1 kg per engine) $15 million.
·        Thermal output 80 gigawatts each, total 24,000 gigawatts (24 terawatts vs. ~16 terawatts world civilization constant energy consumption)
For a projected fleet of 300 ALDEBARAN 2s:
15-24 tons each so 4500-7200 tons U-235 needed or ~1 million tons of natural Uranium (over many years)—comparable to Cold War U235 buildup of HEU for bombs—Russian stockpile was around 1500 metric tons.
Total fleet power output 7200 terawatts during launch (once month per ship for 10 minutes—total fleet flight minutes, 3000)
720 hours month, so 43200 minutes
If all other things were equal these 300 ALDEBARAN 2s would boost world power output by 7 percent for the few minutes powered time per month.
Total U-235 fissioned over 20 year life of 300 ALDEBARAN 2s –72000 sorties, 21600 tons. (equivalent released energy around 16 megatons per ton U-235 or 345600 megatons TNT equivalent—if no accidents during all that time, zero release to the environment (even negative since is literally capable of shooting its waste to the sun, as Anthony Tate has written:)
        After a projection by Max Hunter, if AB Matter engine surfaces were possible, and 200,000 Fahrenheit temperatures were possible, 111,366.483 Kelvin,  800 gigawatts of waste heat could radiate away from 1 square foot (less than a tenth square meter) of engine surface. But because of the blackbody fourth power law,  if the operating temperature were only 30000 F or 16922.039 K, the radiated heat would be a mere 431 megawatts per square foot radiating surface. (That fourth power can be your best friend or your worst enemy, depending on how much you have to radiate and where.)
Cost of the ALDEBARAN 2 to the Moon
One estimate on mining lunar helium 3, which will be covered in more detail in the last section of this series, assumed  $40 million a ton freight fees to the lunar surface in quantity. The estimated He-3 mining equipment weighed half a million tons,
moon, meaning $20 trillion dollars hauling fees,  which is a laughable ain’t going to happen number. (With today’s non-economy of scale, the cost per ton would probably be around $100 million a ton to the lunar surface or even more)
But suppose instead of 100 million the cost was $100,000 a ton– $100 a kilo to the lunar surface. Then half a million tons going up—500,000 tons or 500 million kilograms—becomes a ‘mere’ $50 billion—which might take a consortium of British Petroleum sized companies but at least is congruent to the world we live in now.
 And with a full scale ALDEBARAN fleet the cost of transport up—by which I mean to the lunar surface– would be probably below $5 a kilogram.
If an ALDEBARAN cost $ 22.5 billion to build, could lift 270 million kilograms a year to the lunar surface and did this for 20 years, that is 5400 million kilograms delivered per ship—5.4 megatons delivered— amortized just for ship cost that is $4167 a ton, or about $2 a kilogram. Call it $5 a kilogram including operations and engineering costs and delivering half a million tons to the Moon becomes a mere $ 2.5 billion project—plus of course acquisitions and engineering. Certainly it should be doable for under $10 billion, and a single ALDEBARAN could set up 10 such vast mining operations during a single 20-year career. With 3000 such equivalent plants—massing 1.5 billion tons of equipment brought up—the nucleus of a new solar system civilization could be put in place, in high orbit and on the Moon.
But a note on costs, and yes, $5 a kilogram sounds incredibly cheap and it is—BUT it is not free.
Suppose for example you wanted about half a million tons of co2 gas on the Moon.  If transport was $5 a ton the smart choice would be to mine limestone gravel for say $5 a ton transport it up for another $5 a ton and heat it in a lunar solar furnace. You would get around 440,000 tons of co2 gas per megaton of limestone. The rest would be calcium and oxygen waste.
But at $5 a kilo, not a ton it pays to send up oil coal or butane gas, heat it with lunar iron oxide and get carbon dioxide gas (and water vapor and iron as valuable byproducts) to save on hauling the calcium and oxygen in limestone and just haul the carbon and hydrogen. So cheap isn’t free. But we are so used to hideously expensive in space that cheap is great by comparison
With the ALDEBARAN’s actual costs in this model– $5 a kilogram we can speculate for example of importing neutral argon gas to the moon to foam titanium for export. In a vacuum a little foaming agent makes a LOT of foam, just as a tiny capsule can inflate a huge balloon: There is no outside countervailing pressure to speak of.
If 1 ton of argon would foam 4540 tons of titanium in a ratio of at least 90% pore space, it would be floatable, light enough to probably withstand direct entry and literally could be hurled to the oceans to make corrosion proof thin floating islands and breakwaters for seasteads. The argon transport cost (not counting acquisition cost or operations cost) would be under $1 a ton for such titanium floaters.
The path to Aldebaran is not so impossible as it seems. The fact that it should seem so exotic recalls Jerry Pournelle’s definition of  a dark age—not that you have merely forgotten how to do something but that you have forgotten that it ever could have been done, or in this case, thought quite capable of being done in one more generation.
Remember that in 1960 when proposed no man had yet flown into space unless you count X-15 pilots. If it takes nerve to propose such a huge ship now, what kind of nerve did it take then?
By 1962 we were orbiting a 1.5 ton Mercury capsule. (The empty Atlas sustainer stage weighed considerably more) The Russians were orbiting a heavier ship, the Vostok.
By 1969 We were orbiting well over 150 tons if you count the fuel in the Saturn V third stage as well as the moonship  as payload.
By the early 80s Werner von Braun  projected in a essay (the World in 1984 edited by Nigel Calder) ships of tens of thousands of tons that launched and landed and were refueled only at sea.
Once we had 50-100,000-ton class spaceships, it would have been natural to start considering using first solid core nuclear reactors, then possibly liquid core, then perhaps gas core.  Once you have a low performance 50000 ton gas core reactor, maybe 20 years will see you on the curve to a high performance 50,000 ton gas core reactor. And the Aldebaran, or something like it, would become reality
Consider that now there are over 10,000 major ocean going ships. Commercial vessels, nearly 35,000 in number, carried 7.4 billion tons of cargo in 2007. Total number of ships(with IMO number) as of 2011 is about 104,304.
Consider, that say an Aldebaran flight a month would mean 360,000 tons of cargo in orbit, or 270,000 tons to the lunar surface PER ALDEBARAN PER YEAR. Assume 30 of these things flying, and you get 10.8 million tons to orbit or 8.1 million tons to the lunar surface. Assume 300 Aldebarans in the fleet, and you get 108 million tons to orbit or 81 million tons to the lunar surface per year.
This is several hundred times the lift capacity of the imaginary world of 2001: A Space Odyssey
What could we do with such a capability?
This is the question that a lot of space aficionados stop the analysis at and either go into Star Wars Universe like unlimited fantasy or snap back hard to current NASA limited mindset and experience a quailing of the spirit. But remember, I am not asking you to think, how would YOU get there, I am asking, IF WE WERE ALREADY THERE, how would you use the capability?
Well, what do we use massive transport capability for on Earth? Supporting industry, which in the end, supports reinvestment and personal consumption.
If a 300 Aldebaran vehicle fleet existed, it would be used for nothing less than the industrialization of the Solar System and the settlement of large numbers of people from Earth to offworld dwellings.
.  (And to serve as tugs to propel assembled orbital industrial complexes to escape velocity, to be transferred around the solar system. For example, one can imagine a going out of service ALDEBARAN used to retro a hurled industrial complex into capture orbit around an asteroid, to help colonize that asteroid.)
In 1981 when the Space Shuttle came out, I drew the following hopeful progression—1961, 1 ton capsules to suborbit (Project Mercury) 1981, 100 ton spaceship to orbit.  2001 should by linear trend projection see a —~10,000 ton spaceship to orbit?  By that rate the Aldebaran sized ~ 100,000 ton class ship with 20,000 ton payloads landed on the moon would be due by 2020. 
Never in my wildest science fiction imagination did I imagine that the Space Shuttle would serve for 30 years and be retired with elegiac celebrations of ‘the end of an era’ (instead of ‘we blew 30 years on a socialist space program dead end’) and the next step would be a flashback to a private Project Gemini mass Apollo CM equivalent (the Space X Dragon with room for 7 crammed astronauts) 
In that same year, the 1981 movie Outland
came out starring Sean Connery, and in it was a vision of the required scale of space development of the future. 
The miniature work by such luminaries as Martin J. Bower
In Outland, there was what looked like an elevated offshore platform on the Jovian moon of Io. It had 2144 personnel—1250 labor, 714 support and 180 administrative. It appeared to be about 300 by x 200 meters in size and about 100 meters high on another 100 meters of pole supports and with deep mining elevators with pillar supports going down almost a kilometer into a chasm.

 They used nuclear mining charges in the movie (mentioned in the script, none were shown onscreen.). Although with many weaknesses in design, the scale is of interest here as a realistic sized offworld installation that could get a lot done. The ore to be mined (Titanium) was laughable, the Moon is quite rich in it around the sea of Tranquility. I could believe Lithium, especially in a deuterium tritium fusion powered world (Lithium can breed tritium) that also needed huge masses of lithium batteries. On Io, volcanic moon of Jupiter, there should be a certain amount of magmatic concentration variations of various elements.

 Implied were dozens of other mining operations in deep space. Also laughable were some movie script motivated design flaws such as gigantic single pressurized greenhouse windows JUST PERFECT for an assassin to blow out with a single bullet. But modularized, dispersed greenhouses (with 25:1 solar concentrators given Jupiter’s solar distance) are not only conceivable but also recommended.
What would be the mass of Outland Station? If we say 60,000 square meters in area per ‘floor’ (not continuous but like a stacked piles of offshore platforms, 30 stories high, which can be modeled as 1.8 million square meters. (The portrayed installation had lots of industrial towers, was not blocky office building like, but we are trying for a mass range to do calculations with). Say a reasonable effort to keep things light, as in an aluminum marine vessel, and we might get by with a ton a square meter.
 Say 1.8 megatons for that one mining station and even if constructed 98% of asteroidal processed metals and materials that needs 36,000 tons of more complicated stuff hauled up from Earth in a large traffic, early settlement scenario.
Yeah, I know, it’s just a movie, but that is the scale of mining that would pay if only shipping stuff both up and down was cheap enough.
Remember how deadly the outside environment is to unshielded humans and it will be obvious that you want as robust and massive a containment as you can afford plus many modules to escape from a single point failure. You want massive communities that can rescue people. You want robustness. And you want ensured productivity and safety while working. You also want lots of supplies available on YOUR side of the airlock. One can imagine a century in the future where the 19 hour Moon-Earth trip makes casual resupply a Fed-X kind of thing (Where do you think Space-X’s name inspiration comes from? 🙂 But distant solar installations need years to be able to schedule a major resupply. Huge inventories in redundant storages are a very good idea, and that implies huge installations.
.Consider that Walmart’s logistical chain is 20000 + suppliers  with several hundred thousand line items. That is a big list but for example the list for D-Day was 750,000 line items.
There are huge advantages to having a lot of volume in a station, yes, you have to supply more air but if there is a leak you have more than a few seconds to stop it before you lose consciousness. In Gerard O’Neill’s largest Island Three space colony design a single window blow out would take YEARS to leak out all the air. Plenty of time for repairs—particularly if more than one thing is happening at a time, as often does in ‘unforseeable’ fatal accidents.  What if the choice is between putting out a fire and stopping a leak? That is a choice between breathing poison gas and vacuum dessication in a small module, not so much in a big one that can (in addition) be evacuated. Big installations are a bigger target, and vulnerable in other ways, but they tend to be more robust. And if well designed there is always more than one way to escape to safety.
Interesting spiral grown moonbase pattern from 2001 and ‘Space 1999’—a logical way of expanding in multiple directions from a single point. Note multiple opportunities for escape at any point but the furthest extremities.
As long as we are committing the cardinal sin of drawing engineering proofs from movies, how about the freighter NOSTROMO in Ridley Scott’s 1979 movie ALIEN, which tug towed a refinery with 20 million tons of ore INTERSTELLAR, not just interplanetary.   
The Nostromo was a commercial towing vessel, property of the Weyland-Yutani Corporation. It was hauling an enormous (some 1.5 miles in length) ore refinery and 20 million tons of raw ore, weighing many times the mass of the ship. The ship itself is still substantial, over 60,000 metric tons and almost 245 meters (800 feet) long, including three decks, four holds, stores, engines, and lots of pipes and ducts…
Ah, those pipes and ducts…
OK, given the hitchhiking problem they experienced I can understand not basing a post on that ship, but really that is the scale we need to be talking about, not 1 to 7 man capsules. Not far from 60 years into the Space Age, that is the scale we need to be talking about, but historians may mark an abundance of commercially available 7 man capsules as the beginning of the Second Space Age. But if we want to get a lot done in space, we eventually will need to build and haul a lot. Supersized ships can help in that if they are cheap enough.
As ALDEBARAN 2s reach the end of their service life they may be tasked to final tug duty—a ‘young’ ALDEBARAN 2 may push to escape velocity, a stripped down ‘old’ one may retro in the target system and retire there. One can imagine easily 300 location opportunities for major colonization/industrial/scientific initiatives.
  • Venus orbital station
  • Venus direct retro atmosphere floater colonies (Oxygen balloons float in CO2)
  • Mars moons orbital stations
  • Mars synchronous orbit
  • Mars surface mineral deposit mining colonies
  • Titan direct retro atmosphere floater colonies (well insulated)
  • Europa/Ganymede/Callisto retro land and ice melter colonies.
  • Vast lunar geriatric colonies (less danger from falls, brittle bones)
  • Asteroidal mining colonies
  • Uranus/Neptune floater colonies (nearly unlimited deuterium and helium 3—if an incoming comet had Earth in the cross hairs we could not defend against it today but 4-12 ALDEBARAN 2 stationed in the Outer System with a 13 kiloton mass deuterium bomb could yield a teraton (million megaton) deflection charge against any such intruder)
  • Vast solar power farms and antimatter production (If so, bye-bye gas core as the most important space launch engine)
  • Jupiter Trojan Asteroid Colonies at the Jovian-Solar L4 and L5 points
  • A manned scientific submarine with 100 km cable lowering instrument packages and independent floater robots to probe the Europan ocean for organics and subsea volcanic mineral vents. Mass about like a Typhoon sub today. But well insulated and heated with nuclear power. Who knows what we will find?
  • A 100,000 km linear or ring accelerator in the asteroid belt.
  • Centimeter scale mapping of every worldlet bigger than say 100 km inside the Kuiper Belt. Makes landing a lot safer for first timers to know where the big rocks are.
  • Gigantic gravity focus telescopes for high-resolution studies of the 1000 most likely extrasolar planets after a survey of millions. If we find worlds with oxygen in the atmosphere and can chart alien oceans, our view of the universe will change.
  • Sufficient resettlement to the Kuiper Belt and beyond even the Oort Cloud so that no one disaster can destroy the human race.
This concludes Part 3 of In Praise of Large Payloads.  Part 4 will discuss the scale of massive extraterrestrial industry and the likely products and the practicalities of getting them to market both offworld and on Earth.