A sidebar notes that controversy remains over the Mars meteorite that crashed into Antarctica about 11,000 years  While scientists have demolished most of the evidence that the meteorite contained living creatures, they cannot explain why the meteorite contains a molecule that on Earth is only produced by biological processes.
( ( A sidebar ) ( ( notes ( that ( controversy ( remains ( over ( ( the ( Mars meteorite ) ) ( that ( ( crashed ( into Antarctica ) ) ( ( ( ( about 11,000 ) years ) ( While ( scientists ( have ( ( demolished ( most ( of ( the evidence ) ) ) ) ( that ( ( the meteorite ) ( contained ( living creatures ) ) ) ) ) ) ) ) ) ( , ( they ( ( can not ) ( explain ( why ( ( the meteorite ) ( contains ( ( a molecule ) ( that ( ( on Earth ) ( ( is only ) ( produced ( by ( biological processes ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
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Scientists ruled out the possibility that the meteorite contained life.
( Scientists ( ( ( ( ruled out ) ( the possibility ) ) ( that ( ( the meteorite ) ( contained life ) ) ) ) . ) )
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