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Directed panspermia concerns the deliberate transport of microorganisms in space to be used as introduced species on lifeless planets. Directed panspermia may have been sent to Earth to start life here, or may be sent from Earth to seed exoplanets with life. Historically, Shklovskii and Sagan (1966) and Crick and Orgel (1973) hypothesized that life on Earth may have been seeded deliberately by other civilizations. Conversely, Mautner and Matloff (1979) and Mautner (1995, 1997) proposed that we ourselves should seed new planetary systems, protoplanetary discs or star-forming clouds with microorganisms, to secure and expand our organic gene/protein life-form. To avoid interference with local life, the targets may be young planetary systems where local life is unlikely. Directed panspermia can be motivated by biotic ethics that value the basic patterns of organic gene/protein life with its unique complexity and unity, and its drive for self-propagation. Belonging to life then implies panbiotic ethics with a purpose to propagate and expand life in space. Directed panspermia for this purpose is becoming possible due to developments in solar sails, precise astrometry, the discovery of extrasolar planets, extremophiles and microbial genetic engineering. Cosmological projections suggests that life in space can then have an immense future. == History and motivation == An early example of the idea of directed panspermia dates to the early science fiction work ''Last and First Men'' by Olaf Stapledon, first published in 1930. It details the manner in which the last humans, upon discovering that the Solar System will soon be destroyed, send microscopic "seeds of a new humanity" towards potentially habitable areas of the universe. In 1966 Shklovskii and Sagan proposed that life on Earth may have been seeded through directed panspermia by other civilisations. and 1973 Crick and Orgel also discussed Conversely, Mautner and Matloff proposed in 1979, and Mautner examined in detail in 1995 and 1997 the technology and motivation to secure and expand our organic gene/protein life-form by directed panspermia missions to new planetary systems, protoplanetary discs and star-forming clouds.〔 Technological aspects include propulsion by solar sails, deceleration by radiation pressure or viscous drag at the target, and capture of the colonizing micro-organisms by planets. A possible objection is potential interference with local life at the targets, but targeting young planetary systems where local life, especially advanced life, could not have started yet, avoids this problem.〔 Directed panspermia may be motivated by the desire to perpetuate the common genetic heritage of all terrestrial life. This motivation was formulated as biotic ethics that value the common gene/protein patterns of our family of organic life, and as panbiotic ethics that aim to secure and expand life in the universe.〔〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「directed panspermia」の詳細全文を読む スポンサード リンク
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