Robert Duncan Enzmann, 1924 – 2020
First published in Planetology and Space Mission Planning, Second Conference, published by the New York Academy of Sciences, 1969.
The First Conference on Planetology and Space Mission Planning was directed toward reviewing the methods of optimizing the costs of space missions in relation to information gain. It was pointed out in the Preface to that symposium that the United States, the Soviet Union, and a consortium of other European counties were engaged in the effort to extend unmanned and manned explorations through and eventually beyond the Solar System. These explorations, it was realized, would consume years, natural resources, and power and would entail economic adjustments approaching and probably exceeding the expenditures needed to conduct the First and Second World Wars.
Authors from the fields of industry, finance, education, and government were brought together to discuss the developments that would be needed in instrumentation, communications, and particularly vehicular technology and propulsion. Then as now, we were concerned about protecting alien and terrestrial environments from the various kinds of contamination that might have to be guarded against as a byproduct of these journeys. None wanted “a figurative spade rushed through the Dead Sea Scrolls’ in a push to ‘get the gold, such as would occur if a biosphere were destroyed or grossly altered. Within these precautionary limits, the First Conference emphasized commensurate information return.
Mission optimization was approached by reviewing environmental classifications, measurement methods, and their classification under signature theory, measurement, and signature valuation. Methods used by radar signature analysts were expanded and suggested as useful for all modes of sensing, measuring, and information gain. For the study of other celestial bodies, an Expanded Theory of Geomorphic Order was suggested. Several approaches to judging the relative values of numerous but limited numbers of measurements by multisensory systems were used to form value hierarchies.
In a post-symposium panel discussion, it was agreed that any generalized approach to planning space missions for optimum information gain must be built around better ways of deciding which measurements are most important. It was suggested in the discussion that a thermodynamic basis would eventually be perfected as a method for judging where and with which features maximum amounts of information re-associated, which measurements would be most valuable, and in what order they should be made. This approach has followed and expanded in the Second Conference.
Both the first and second Monographs have four sections:
- Space Mission Planning
The sections are more comprehensible if their introductions are read first.
In the Second Conference, the principles of spending for information gain have been expanded. It is suggested that they can be used to optimize spending for:
- Energy gains, an example of which would be trade-off studies considering the use of solar cells in a satellite so that the system can gain energy from its solar environment rather than relying exclusively on its internal energy sources.
- Gains in raw materials, cases of which would include trade-off studies considering transportation of liquid air to the Moon for respiration vs. transporting a plant there which would extract oxygen from silicates by the use of solar or nuclear power; and liquefying gasses from the atmosphere of Mars for use with Nerva-type nuclear engines vs. transporting bulk fuel to mars for the return trip.
The option arises of building organic and/or mechanical processing plants where food and components could be manufactured. An example, among many, would be the cost-effectiveness of transporting sheet metal to the Moon for fabrication of buildings and other structures vs. manufacturing right there.
It might be asked here how a massive unmanned and manned space effort could be an economic proposition for any economy, in spite of the fact that portions of it can be made more cost-effective by careful planning. The answer to this is that mankind is on the threshold of the greatest expansion of our ecological niche since life crawled out of the seas. In the writer’s opinion, the space effort in the Solar System should have two great objectives, which even at this time complement each other. The first objective is to make the Earth a better place to live and to do so in the most effective way possible. The second objective is to prepare for manned interstellar colonizing expeditions. The writer would like to indicate very briefly just what benefits have accrued to mankind from space systems and how these economic benefits come from space systems that are positioned ever more remotely from the surface of the Earth:
- Atmospheric probes to measure atmospheric and ionospheric parameters have been used for years and are used because they are convenient and cheap.
- Communications satellites are economical and useful and provide data relays that cannot be supplied by cables. It is doubtful that mankind would be any more willing to part with his communications satellites than he would his weather bureaus.
- Weather satellites have for the first time provided global weather coverage; coverage of this type from the ground would be literally impossible.
- In the immediate future, the use of the following systems can be foreseen:
Direct, synchronous orbit-to-home television relay satellites; ionospheric sounding satellites which would make broadcasting and cable routing and loading easier.
Navigation satellites for used by all ships and aircraft which will be free from almost all-weather interference.
Oceanographic satellites for reporting sea states on a real-time basis, locating plankton and fish concentrations, measuring water temperatures, and even following schools of fish.
Solar satellites to report on flares, thereby easing the burden on wireless, cable, and satellite groups who route communications.
- In the near future, we might expect wireless and television relay stations to be based on the Moon, perhaps with optical telescopes for astronomers.
- In the more distant future, permanent nets of weather, ionospheric, and seismic stations can be expected to be placed on the Moon, Mercury, Venus, and Mars. Observation of these patterns should be helpful in understanding the more complex geospheres of the Earth.
We have developed a viable and very profitable space industry since the first satellite, Sputnik, circled the Earth some years ago, chirping like a tired cricket. Many learned voices told us how useless it was, just as many said that Lindbergh’s flight across the Atlantic was an interesting stunt.
The Second Conference on Planetology and Space Mission Planning was very much underlain by an organic theme that the prime motive of all life – and this includes mankind who often presume to be the measure of all things – is to expand to fill its environment. This postulate should be accompanied by a second, suggesting that when an environment is not suitable, the living forms have the options of perishing, migrating, or changing through genetic or technological development. This should be still further qualified by indicating that life changes continually by mutation and selective survival; often, the mutated groups are able to thrive in environments hostile to their ancestors. The writer does not claim to have originated these ideas. They appear in most introductory biology texts. They are, however, basic to the space effort and are worth indicating here. The space effort is organic, and today, at the beginning of the manned space effort, mankind may really stand at the dawn of history.