Krafft Arnold Ehricke

Krafft Arnold Ehricke (March 24, 1917 – December 11, 1984) was a rocket-propulsion engineer and advocate for space colonization.

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 * Humanity faces the most complex task of its history so far. Stated in a solution-oriented way, it is necessary gradually to reorganize this planet at two levels. One must deal with the competing necessities of biosphere and mankind with all their environmental and climatic consequences. On the other level, it is necessary to resolve the demands of competing nations and worlds within mankind's hierarchy of socioeconomic developmental levels and the "Christmas tree" of sociopolitical, ideological, and military consequences.
 * The Extraterrestrial Imperative (1978)


 * The economic function of space industrialization is to generate jobs on Earth, not in space.
 * The Extraterrestrial Imperative (1978)


 * If God wanted man to become a spacefaring species, he would have given man a moon.
 * Lunar Bases and Space Activities of the 21st Century (1985)