As we've said, because of the severe temperatures, it may take millions of years for these molecules to form, thus precluding the possiblity of the activity of life forms as sophisticated as bacteria. Moreover, there is no atmosphere to speak of in comets in residence in the Oort cloud, and only a transient atmosphere in comets making a perihelion passage. Nevertheless, over the age of the solar system, and because comets making a perihelion passage loose a portion of their friable surface, it is thought that comets may have brought some of life's beginnings to the inner solar system where they could better thrive.
Read more about this possibility by reading our life section. Read more about the sort of unsophisticated life forms found on the primordial Earth by taking the Exporatour of Life on Earth.
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