THEORY OF PANSPERMIA -
Arrhenius (1908) postulated the cosmic panspermia theory that claims that organisms existed throughout the universe, and their spores, etc., could freely travel through space.
Helmholtz (1864) put forward the meteorite concept and according to this concept, an alive germ came to earth by the support of meteorite particles falling from other planets.
The recent researches disproved the concepts of inter-planetary exchange of viable spores.