Could life have begun in comets? This hypothesis has been advanced for some years by two astronomers, Fred Hoyle of England and Chandra Wickramasinghe of India. This hypothesis is based on the fact that since 1968, through the method of infra-red and radio radiation, many rather complex organic molecules have been found in galactic gas clouds and dust as well as in many types of objects (meteorites, some satellites of the larger outer planets and comets). According to this hypothesis, comets collect all of the organic molecules they encounter during their long voyage in space. These molecules would find themselves in an environment with the elements necessary for life due to the fact that comets contain water (even though a large part consists of ice). These molecules would "wake up" only when the comet passes near the Sun and the temperature rises. At this point, through the right combination of organic material, life would begin with the formation of micro-organisms. These micro-organisms could then be deposited on a planet when the comet passes close by and covers the planet with its tail. Naturally, the planet must be close enough to the Sun, like the Earth, to have the necessary environmental conditions so that the comet still maintains the tail produced by the solar wind. The weak points of this theory are that it has not been demonstrated that comets really contain micro-organisms, and that interstellar clouds, which are full of organic molecules, seem to be beyond the "reach" of comets. Based upon the theory of Oort's cloud, they do not seem to go beyond a short distance (in cosmic terms) from the solar system.
Could life have begun in comets? This hypothesis has been advanced for some years by two astronomers, Fred Hoyle of England and Chandra Wickramasinghe of India. This hypothesis is based on the fact that since 1968, through the method of infra-red and radio radiation, many rather complex organic molecules have been found in galactic gas clouds and dust as well as in many types of objects (meteorites, some satellites of the larger outer planets and comets). According to this hypothesis, comets collect all of the organic molecules they encounter during their long voyage in space. These molecules would find themselves in an environment with the elements necessary for life due to the fact that comets contain water (even though a large part consists of ice). These molecules would "wake up" only when the comet passes near the Sun and the temperature rises. At this point, through the right combination of organic material, life would begin with the formation of micro-organisms. These micro-organisms could then be deposited on a planet when the comet passes close by and covers the planet with its tail. Naturally, the planet must be close enough to the Sun, like the Earth, to have the necessary environmental conditions so that the comet still maintains the tail produced by the solar wind. The weak points of this theory are that it has not been demonstrated that comets really contain micro-organisms, and that interstellar clouds, which are full of organic molecules, seem to be beyond the "reach" of comets. Based upon the theory of Oort's cloud, they do not seem to go beyond a short distance (in cosmic terms) from the solar system.
