FIRST STEPS TOWARD SPACE - Smithsonian Institution Libraries

30 SMITHSONIAN ANNALS OF FLIGHT
In all the preceding sections we have only considered the theoretical possibility
for a body with special properties to travel between the earth and the moon. This is
a problem of pure mechanics which does not really answer the question of whether
man will be or will never be able to leave his world to explore others.
The complete study of the question will lead to the study of the physiological conditions
that must be fulfilled so that life will be possible under such conditions.
The progress made in submarines can already make us consider as quite feasible
in the future the regeneration of an atmosphere which has been confined for some
hundred hours.
The question of temperature deserves being particularly considered. It is often
said that the interplanetary spaces have an almost absolute zero temperature. The
author believes it is false.
The concept of temperature is only related to material bodies and therefore a
vacuum cannot have any.
If the amount of heat absorbed per unit time by our vehicle is less than the quantity of
heat that it radiates, its temperature will decrease. If the amount of heat received and
absorbed is greater than the amount that is radiated, the temperature will increase.
It would therefore be possible to construct a vehicle in such a way that one half of
its surface would be of a polished metal and the inside insulated. The other half of
the surface, for example, would be covered of copper oxide to give a black surface.
If the polished face would face the sun, the temperature would decrease. In the
opposite position, the temperature would increase.
All the difficulties that we have just considered do not seem to be theoretically
impossible. But a new difficulty will arise which although a mechanical solution
offers itself, will nevertheless complicate further the problem.
In fact, in the calculations related to the vehicle's journey from the earth to the
moon, we have considered that we were applying an acceleration
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and this up to a distance of 5780 km from the earth's surface. During all this phase
of the voyage, the travellers would therefore have the impression of weighing ^}/{Q
of their weight.
One may hope that as unpleasant as this sensation may be it will not cause any
disturbance to a human organism. But what is most alarming is what will happen
at the instant of sudden stoppage of propulsion. At this moment, the traveller would
suddenly cease to have any weight and he would have the sensation that both he and
his vehicle were falling in a void.
If the human organism cannot go through such vicissitudes, we would have to
replace the absence of a gravitational field by creating constant artificial acceleration
produced by the motor. If this acceleration is made equal to gravity, the traveller
will constantly feel he is weighing his normal weight, without any consideration of
the fact that he may or may not be in the gravitational field of a planet.
It is obvious that this kind of a process would introduce a very important difficulty
with regard to the amount of energy which would become necessary, and would