Chariots of the Gods Read Free

big as a present-day ocean liner and would therefore have a launching weight of about 100,000 tons with a fuel load of 99,800 tons, i.e. an effective pay load of less than 200 tons.
    Impossible?
    Already we could assemble a space-ship piece by piece while in orbit round a planet. Yet even this assembly work will become unnecessary in less than two decades, because it will be possible to prepare the giant space-ship for launching on the moon. Besides, the basic research for the rocket propulsion of tomorrow is in full swing. Future rocket motors will mainly be powered by nuclear fusion and travel at nearly the speed of light. A bold new method, the feasibility of which has already been shown by physical experiments on individual elementary particles, will be the photon rocket. The fuel carried on board the photon rocket enables the rocket's velocity to approach so close to the speed of light that the effects of relativity, especially the time dilation between launching site and space-ship, can operate to the full. The fuel supplies will be transformed into electro-magnetic radiation and ejected as a clustered propulsive jet with the speed of light. Theoretically a spaceship equipped with photon propulsion can reach 99 per cent of the speed of light. At this speed the boundaries of our solar system would be blasted open!
    An idea that really makes the mind reel. But we who are on the threshold of a new age should remember that the giant strides in technology which our grandfathers experienced were just as staggering in their day: the railways, electricity, telegraphy, the first car, the first aeroplane. We ourselves heard music in the air for the first time; we see colour TV; we saw the first launching of space-ships and we get news and pictures from satellites that revolve around the earth. Our children's children will go on interstellar journeys and carry out cosmic research at technical faculties in the universities.
    Let us follow the journey of our imaginary space-ship, whose goal is a distant fixed star. It would certainly be amusing to try to imagine what the crew of the space-ship did to kill time on their journey. Because however vast the distances they covered and however slowly time might crawl along for those left behind on earth, Einstein's theory of relativity still holds good. It may sound incredible, but time on board the space-ship travelling barely below the speed of light actually passes more slowly than on the earth.
    If the space-ship travels at 99 per cent of the speed of light, only 14-1 years pass for our crew on their flight in the universe, whereas 100 years go by for those who stay at home. The difference in time between the space travellers and the people on earth can be calculated by the following formula, given by the Lorentz transformations:
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    (t = spacet-travellers' time, T=time on earth, v= speed of flight, c= speed of light).
    The speed of the space-ship's flight can be calculated by the bask rocket equation worked out by Professor Ackeret:
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    (v — velocity, w = speed of jet, c = speed of light, t = fuel load at launching).
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    At the moment when our space-ship is approaching the star which is its target, the crew will undoubtedly examine planets, fix their position, undertake spectral analyses, measure forces of gravity and calculate orbits. Lastly they will choose as landing-place the planet whose conditions come closest to those of our earth. If our space-ship consists solely of its pay load after a journey of shall we say eighty light years, because all the energy supplies have been used up, the crew will have to replenish the tanks of their space-craft with fissionable material at their goal.
    Let us assume, then, that the planet chosen to land on is similar to the earth. I have already said that this assumption is by no means impossible. Let us also venture the supposition that the civilisation of the planet visited is in about the same state