Ancient plant fragments preserved by meteorite impact glass

Meteorites have the potential to cause widespread ecological damage. But a new study suggests that "impact glass" from an asteroid collision can also help preserve ecological history -- trapping bits of organic material and offering geologists a snapshot of ancient plant life. A team of researchers at Brown University have located fragments of leaves and organic compounds preserved inside the impact glass from several ancient meteorite collision sites in Argentina. Impact glass is the rock formed via shock metamorphism, a result of the extreme heat and high pressure of impact events. The scientists involved on the study say their findings are counterintuitive, as one would expect plant material to be carbonized at such high temperatures. But when attempting to replicate shock metamorphism in the lab, researchers were able to show that traces of plant material are preserved when rocks are formed at above 1,500 degrees Celsius. "I was surprised to find the amount of plant matter preserved," Dr. Kathie Thomas-Keprta -- a researcher at NASA's Johnson Space Center in Houston -- told BBC News. The researchers, who published their findings in the journal Geology this week, say their discovery demonstrates how meteorite fragments could hold the key to finding evidence of alien life. "Next we need to evaluate if microbes can also be preserved by this mechanism," Dr. Thomas-Keptra said. "Then, we need to collect the appropriate samples on Mars."