Review:Population Bomb
Paul R. Ehrlich wrote the revised edition of The Population Bomb which was published in 1971. The importance of the book is that it seems to be the voice of the Zero Population Growth crowd, and their arguments do not seem to have changed much in 45 years. In 1971 the argument was that starvation was imminent and even immediate population control will not be enough to completely prevent famine in several places. The argument has been revised to the extent that it is claimed that population will cause starvation but the date was not well expressed. There is some danger of famine such as happened in Europe in 1848 because of crop failure, but the ZPG crowd fail to take into account the expertise of agricultural producers. Farmers tend to know their market and not invest in extra production that they will not be able to sell. We have not had much shortage of food except where war prevented agriculture and prevented aid to the hungry. There is some shortage of money to buy food but if there were more money in the hands of the hungry, more food could be produced. Salt tolerant crops could be grown on desert land by the ocean if it were irrigated with sea water. Mushrooms could be developed to grow on much wood that currently lies dead in the forest until it provides fuel for a forest fire. New techniques of producing more only need money to be realized.
The big problem with the book is that on page 5 Ehrlich refers to the "logistic problems of moving billions of people off the Earth" as "insurmountable." I describe how these problems could be solved in Eddy Current Brake to Orbit. There is more than one launch technology that could be used, such as Wheel Launch to Orbit. Then this defeatist goes on to write that it would take only about 50 years to populate Venus, Mercury, Mars, the moon and the moons of Jupiter and Saturn to the same population density as the Earth. Here he was using the assumption of a continuing rate of doubling once per 35 years. A person can find a way to fail at anything if they try hard. The proper way to colonize the solar system is not covering the surface of Venus, Mercury, Mars, the moon and the moons of Jupiter and Saturn but rather mining these bodies down to the core and converting them into space habitats.
In the case of Venus this could be done by building a shade at the Venus/Sun L2 point to cause the atmosphere to freeze out and leave the entire planet available to be mined. The shade could be a cone shaped structure with the 90 degree point pointing at the sun and the base turned toward Venus. The cone would be supported by ring structures in planes parallel to the base with the rings containing masses that move similarly to the L2 halo orbit but somewhat faster and constrained to follow a circular path. Each ring would have two sets of masses circling in opposite directions with speed and spacing computer controlled. The rings would be connected in order from smallest to largest fixing there relative positions with perhaps two miles space between each ring and the next. Attached to the rings on stalks would be three mile diameter spinning disks of shiny foil to act as umbrellas, shading the ring structure and shading Venus. The atmosphere of Venus would condense out in a year or so of torrential rains and eventually freeze solid. The structure of the rings and the structures between them would be active truss structures to allow gravitational perturbations from Jupiter to slightly alter the shape of the shade without breaking it.
By mining a number of planets and moons to the core I came up with material enough for 3.8 E 14 space habitats (380 million million) for more than 1.0 E 19 people (10 billion billion) at about 500,000 metric tons of habitat per person.
