Allan Hills 84001: Difference between revisions
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[[File:ALH84001 structures.jpg|thumb|300px|The electron microscope revealed chain structures in meteorite fragment ALH84001]]
Under the [[scanning electron microscope]] structures were revealed that some scientists interpreted as [[fossils]] of [[bacteria]]-like lifeforms. The structures found on ALH84001 are {{Nowrap|20–100 [[nanometre]]s}} in diameter<ref>Allan H. Treiman, [https://www.lpi.usra.edu/lpi/meteorites/life.html Fossil Life in ALH 84001?]</ref>, similar in size to theoretical [[nanobacteria]], but smaller than any [[cellular life]] known at the time of their discovery. If the structures are fossilized lifeforms, as was proposed (the bogenic hyothesis), they are the first solid evidence of the existence of [[extraterrestrial life]]. Terrestrial contamination was unlikely.<ref>{{Cite journal|author=McSween, H. Y.|title=Evidence for life in a martian meteorite?|journal=GSA Today|volume=7|issue=7|pages=1–7|date=1997|pmid=11541665}}</ref>
The announcement of possible [[extraterrestrial life]] caused considerable controversy. When the discovery was announced, many conjectured that the fossils were the first true evidence of extraterrestrial life—making headlines around the world, and even prompting the [[President of the United States]] [[Bill Clinton]] to make a formal televised announcement to mark the event.<ref name="clinton">{{cite web|title=President Clinton Statement Regarding Mars Meteorite Discovery|url=http://www2.jpl.nasa.gov/snc/clinton.html|last=Clinton|first=Bill|publisher=NASA|date=1996-08-07|accessdate=2006-08-07}}</ref>
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