Richard Hoover published a paper in 2011 claiming to have found extraterrestrial microbes in meteorites.
NASA scientist Richard Hoover published a paper March 4, 2011, claiming to have found fossil evidence for cyanobacteria in carbonaceous meteorites from outer space. Hoover observed slices of meteorites through scanning electron microscopes, and identified filaments and structures that he said resemble the tiny single-celled algae.
Hoover was criticized for publishing his paper in the Journal of Cosmology. Other researchers said the study was conducted thoroughly, but it was too soon to say for sure whether the claim would hold up.