PANSPERMIA HYPOTHESIS

The panspermia hypothesis posists that Earth life might have arrived rather than originated here. That life on the Earth came from micro-organisms or chemical precursors of life present in outer space and able to initiate life forms on reaching a suitable environment. Some scientists argue that in the ancient past the Martian environment was more conducive to life's emergence than that of the Earth. And it's not terribly uncommon for the two planets to exchange material in the form of rocks and dirt blasted into space by an asteroid strike. Orbital dynamics dictates that it's much easier for Martian material to reach Earth than the other way around, so we may all be Martians according to this line of thinking. It may even be possible for life-forms to move from one star system to another, some panspermia adherents say. Meteorites and comets are the most discussed methods for transportation. For example hardy microscopic spores could be transported vast distances by stellar radiation pressure or frigid bodies orbiting far from their parent star could come under the gravitational sway of a neighboring star. Extremophile spores are one such example which are hardy enough to survive the extreme condition of space. Panspermia, if it occurs, does not solve the problem of the origin of life but merely relocates that event to somewhere else in the Universe.