SPACE FUTURE SPACE HOTEL TOURISM, AN IDEA OF A SPACE HOTEL IN EARTH ORBIT

1. How to get it in orbit - it must consist of sections, that can be separately launched from Earth and assembled in orbit.
2. A design, that can start small (lower costs), but can be extended later for more passenger accommodation.
3. A design that utilizes all its parts with a function, so it doesn't become bigger than what useful functions require.
4. To provide the comfort of "gravity", without having to build a very large (expensive) rotating wheel-shape.
5. A sufficient energy supply system, that neither is too expensive, nor too large and in the power range of 25 - 100 kW
6. A highly reflective surface against solar radiation, to keep the temperature inside down (think of a termo bottle - same principle)
   and black-body-type cooling radiators, to cool off excessive heat (actually all energy 'used' in the spotel).
   I have described this problematic for settlements on the Moon, where the conditions are even more complicated (largely ignored by the artists-designers).
7. A docking system for safe transfer of (untrained) guests, from-to a space shuttle.
8. To provide guest accommodation, service and entertainment for around a week's stay.
9. Last but not least a safe way to bring people in and out of orbit. I am not a rocket-aviation engineer and must leave that part to the according experts to solve, though I do have some basic ideas they might consider for future developments - have to think more about it. See my calculations on gravitational orbits here

Note: "spotel" is not thought as a trade name (trademark protected already by PanAmSat Corporation), but as a new word for a new object, just like 'motel', 'botel', etc.

I have worked on a design that can do al this, though I may have missed a view criteria, that I am not aware of. If not, the concept is clear as I present it here. A rotating spotel is a must, because a longer stay of several days, a week, would not be 'comfortable' for untrained guests, who want to enjoy themselves. Nevertheless, they would like to experience weightlessness, but not all the time. The center part of the rotating spotel provides the opportunity to experience weightlessness at any convenient time. It's 'natural' to think of a rotating wheel, a torus, but that would not comply with points 2, 3 and 4 above, because it must become very large, like a mile in diameter, to give any idea of a 'flat' floor of say 30 feet length. The 'spokes' of the wheel (several would be needed to give the required mechanical strength), would also become very long and constitute rather useless volumes, as they must be large enough in diameter to convey people and materials from and to the center section, where the docking facility for space-shuttles necessarily must be. So the volume of the torus becomes far too large to start on a small scale with just a few guests - it could accommodate at least a hundred of them. Thus the total initial investment costs would become very large and the pay-off time beyond all economic proportions.

Only in the very remote future, when space tourism has become as common as air traveling is today, one could think of such huge, wheel-shaped spotels, because they have the very big advantage of rotating very slowly, thus giving a more steady view on Earth. In the design that I propose here, the spotel has a largest diameter of around 110 feet, which requires it to rotate with around 6 revolutions per minute (rpm) to generate a gravity effect of 0.5 G (50% from Earth gravity). Of course, less may do and so, at a speed of 3 rpm, the gravity effect would be the same as on the Moon. But that would only be in the outer guest suites, whereas sections closer to the spotel's center would gradually have less gravity. I would say that 5 rpm (0.4 G - Mars' gravity) would be the minimum required speed. Naturally, the 'arm' sections can be made longer for lower rotational speeds, but I tried to keep the total size of the spotel as small as possible, not only for economical reson, but also to keep the mechanical loads on the whole structure down (also something the artists designers don't 'waste' any thoughts on).

Thus, in order to keep the dimensions within limits, the main guests quarters (the living-suites) are positioned perpendicular to the plane of rotation, thus giving a perfectly 'flat floor' experience over their full length. But not over their full width and so they are kept narrow, around 8 feet wide inside, by which only a very slight cross-sloping feeling occurs - one wouldn't notice it in practice.

Initially, as shown in the header picture above, only two guest units are attached to the center unit, each giving accommodation to four guests and two crew members.

When a larger guest capacity is required, a maximum of six more units can be added pair-wise, increasing the total accommodation capacity to 32 guests and 16 crew members (or less crew members, using the extra accommodation for less-paying, second class guests).

Then the fully extended spotel looks like shown in the images on the left and right.

Of course, the living-suite units can be made longer, basically any length, but I have kept them on 40 feet, in order to keep the dimensions down and thus the lowest initial costs for building a basic spotel. With longer suite units, one could double the guest capacity to 8 guests per unit (each containing two suites), thus 64 (first class) guests in the max extended version (more would not be feasible, as follows from the interior drawings on the next pages).

Moreover, larger units have more mass, needing a stronger structural design. Another prohibitor is the life support system, that possibly cannot serve that many people, something I cannot know at this point (but the artist-designer, has no thoughts on such "given" features)

With this basic design concept fixed, we have the actually largest difficulty left to overcome and that is the energy supply system.

1. Solar panels just give too little, as we are looking at an uninterrupted 25 to 100 kW required power availability, possibly more and depending on how many units are in use. Besides, solar panels need to be directed towards the sun and that is quite difficult to do on a rotating platform, half, or part of the time being in the Earth's shadow as well.

2. Fuel cells with the required power capacity would take up a very large volume and would anyway become too expensive. Moreover, they need a constant supply of hydrogen and oxygen, rather difficult to handle and to keep available in due quantities, to say the least. Btw, ever heard of hydrogen as an 'energy source'? Read here, what a bad joke that is. Nevertheless, fuel cells would be the only usable technology available today, apart from....

3. Nuclear power. This would be the only option left, but I haven't heard yet of a nuclear reactor that delivers between 25 and 100 kW in heat power. Even if, how to convert into electricity? The smallest steam turbines range in the Megawatts (cannot be scaled down, due to excessive rotational speeds resulting). Positive displacement expanders would be the only option, but they have a very low efficiency. Furthermore we have the problem of dangerous radioactivity from the reactor. Such a nuclear power system would therefore have to be placed on a large distance from the spotel, because we can't use heavy shielding materials (such as led).

4. My idea is to use the low quality heat, that is produced by the nuclear waste from power plants. As this is low-active material, it could be used within safety-limits, yet placed in a tank on the shown 'mast' of the spotel, on a safe distance from the people inside there. However, there is no conversion technology available for that today, because the low-quality heat from nuclear waste cannot generate the around 900 F steam that is needed for some reasonable conversion efficiency. On analyzis of forgotten experiments, done by nobody less than James Watt around 230 years ago, I found a property of steam that would allow the development of a technology with high enough efficiency - this is what I intend for use in the spotel.

If we cannot do this, than options 2 and 3 are the only one I can imagine and I don't deem it impossible, just much more expensive and complicated. On the next pages you can see the detailed design of this spotel and how it works, but first you may want to look at the one I have launched myself already and filmed from above in my private space shuttle (believe it, or not...).

Click here to see the spotel in action, or go to the description page instead