Microbes born on Earth are already pre-adapted for journeying through space, living in space, and not just surviving but flourishing in radioactive environments where they are continually exposed to radiation by ions similar to what might be encountered in a nebular cloud.
In 1958, physicists discovered clouds of bacteria, ranging from two million bacteria per cm3 and over 1 billion per quart, thriving in pools of radioactive waste directly exposed to ionizing radiation and radiation levels millions of times greater than could have ever before been experienced on this plane.
The world’s first artificial nuclear reactor was not even built until 1942. Prior to the 1945, poisonous pools of radioactive waste did not even exist on Earth. And yet, over a dozen different species of microbe have inherited the genes which enable them to survive conditions which for the previous 4.5 billion years could have only been experienced in space. (These radiation-loving microbes include Deinococcus radiodurans, D. proteolyticus, D. radiopugnans, D. radiophilus, D. grandis, D. indicus, D. frigens, D. saxicola, D. marmola, D. geothermalis, D. murrayi).
Microbes from Earth are preadapted to surviving conditions which they have not encountered on this planet. Therefore, they must have inherited the genes which made survival in space possible; and this means these genes were acquired from microbes which had lived in space. It is this adaptation which made them the perfect vehicle for spreading the genetic seeds of life throughout the cosmos.
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