What is panspermia theory and why is this idea didiscarded

HI NIHALA

ACCORDING TO THIS THEORY IT IS SAID THEM LIFE CAME ON EARTH FROM OTHER PLANETS IN FORM OF SPORES. IT MEANS THAT SPORES COME FROM ANY OTHER PLANET WHIICH FURTHER DEVELOPED TO FORM OTHER LIFE FORMS.

THIS THEORY FAILS BECAUSE THE ARGUMENT IS FROM WHERE THESE SPORES CAME AND HOW LIFE ORIGINATES ON THAT PLANETS

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