Ex-News Junkie
Slow Boat versus Hot Rod to the stars
Sat Nov 4, 2017 11:52pm
2001:1970:5c22:6100:240b:7e12:2426:e0fe

Slow BoatHot RodLimiting Factor
okXpropellant
okXshielding
okXrefuel/resupply
okokmaintenance
okokgeometry & structural stability
Xokg-forces
Xokfreedom of movement of passengers and crew


Referring to the above table as a comparison between a "Hot Rod" versus a "Slow Boat" to the stars, one can quickly see the differences. The slow boat has fewer negatives, and they are entirely different:

1. Propellant. Clearly the Hot Rod fails here. The rocket equation would require a positively unachievable amount of fuel to accelerate any sized manned spacecraft to approaching the speed of light. In fact, even in the near-vaccum of interstellar space there is enough gas to result in aerodynamic drag on the Hot Rod, enough drag to balance the thrust from the engines, and likely preventing the Hot Rod from getting anywhere near the speed of light. In contrast, the Slow Boat doesn't try to break any records and gets there eventually, no matter the speed, and minimizes the amount of fuel used during acceleration and deceleration, likely not experiencing any significant drag at all.

2. Shielding. Again the Hot Rod fails. Forget micrometeorite damage - even at 10% of lightspeed a single proton hitting the hull of the ship would result in a shower of gamma rays flooding the interior and killing everything on board. There is no known shielding system that would protect against this hazard. In contrast, the Slow Boat could use a basic Whipple Shield to protect against micrometeorite impacts, and there would be no threat at all from relativistic protons, unless the protons were themselves traveling at relativisitc speed, e.g. cosmic rays. This hazard would be minimized on a Slow Boat starship.

3. Refuel/Resupply. Again the Hot Rod fails. The Hot Rod would have expended such a huge amount of fuel to get up to speed that rendezvous with Oort Cloud objects to refuel or resupply other materials would be impossible while en-route. Presumably there would only be enough fuel to decelerate upon arrival at the ultimate destination. A Slow Boat would not be moving appreciably faster than the average Oort Cloud object and would therefore not have too much problem maneuvering to match speeds, rendezvousing, refueling, then continuing on the voyage. The Slow Boat could likely carry a significant reserve of fuel just for this purpose.

4. Maintenance. Both classes of starship pass this test. The Hot Rod would have all crew able to work at any time. The Slow Boat could manage rotating crew schedules to ensure maintenance is carried out continuously.

5. Geometry & Structural stability. Both classes of starship also pass this test. The Hot Rod would have a necessarily simple, compact geometry that does not fail under thrust. The Slow Boat might be very large, ring shaped, and therefore not compact or simple. However there is no reason to expect it to be unable to maintain structural stability under high efficiency, low thrust propulsion, especially if it has many thrusters that are distributed across its bulk.

6. G-forces. Here the Hot Rod wins over the Slow Boat. The only time the Hot Rod would experience g-forces would be during acceleration and deceleration. The rest of the time it would be zero-g or perhaps minimal rotation. The Slow Boat with its relativistic circular accelerator would generate trillions of gees. The only way to balance these forces is via diamagnetic levitation of all objects in the accelerator, whether passengers & crew, or other supplies. Therefore the Slow Boat would require a speculative system to generate high field magnetism on the order of one million Teslas, or 10000-times more powerful than the current world record.

7. Freedom of movement of passengers and crew. Again the Hot Rod wins as there wouldn't be any inherent reason for the crew to be immobilized. On the Slow Boat relativistic ring however, all objects would have to be immobilized since even small movements can drastically affect the Lorentz factor, or time dilation, experienced by those objects. These effects could amount potentially to many years, and therefore potentially affect the viability of those objects that age faster than intended. Therefore objects would have to be immobilized. Passengers and crew could be immersed in a VR or Augmented Reality environment as a distraction. Therefore, although this isn't a showstopper technically, it might be a showstopper for those who do not accept the limitations to "fundamental" freedoms that come with living in space and traveling to the stars.

Notwithstanding the development of key technologies, the Slow Boat to the stars is the overall winner. It simply has fewer obstacles to making it work.


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