February 16, 2010
Scientists Find Organic Molecules In Meteorite
Experts said a meteorite that crashed into Earth 40 years ago contains millions of different carbon-containing, or organic, molecules, BBC News reported.
Scientists say that such organic compounds are life's building blocks, and are a sign of conditions in the early Solar System, yet they are not necessarily a sign of life.
The Murchison meteorite could even be older than the Sun, according to the research published in the Proceedings of the National Academy of Sciences.
Philippe Schmitt-Kopplin, lead researcher on the study from the Institute for Ecological Chemistry in Neuherberg, Germany, said they were really excited about the discovery.
"When I first studied it and saw the complexity I was so amazed. Having this information means you can tell what was happening during the birth of the Solar System," said Dr. Schmitt-Kopplin.
He explained that meteorites are like some kind of fossil, in that when you try to understand them you are looking back in time.
The identification of many different chemicals shows the primordial Solar System probably had a higher molecular diversity than Earth, the experts said.
The meteorite landed in Murchison, Australia in 1969 and has been examined before by scientists looking for specific compounds. However, this is the first non-targeted analysis that has confirmed a huge variety of carbon-based chemicals.
The team was able to identify 14,000 different compounds during a study using high-resolution analytical tools, including spectroscopy. The team extrapolated the number on the basis of previous analyses done on natural organic matter.
The ultra-high-resolution mass spectrometry used showed only a fraction of the compounds that exist in the meteorite while it was being analyzed. But the prior studies allow them to make a good estimate of the total number of compounds.
"We were very conservative in our calculations and interpolation. We have to crush a few milligrams from the core of the meteorite to enable the extractions with solvents and thus we only see the extractable fraction," said Dr. Schmitt-Kopplin.
The Murchison meteorite could have originated before the Sun was formed over 4.65 billion years ago. It probably passed through primordial clouds in the early Solar System, picking up organic chemicals, the researchers said.
The findings might contribute to the debate over how life on Earth originated, according to Schmitt-Kopplin.
He added: "I guess many people working in these fields with access to this knowledge will have some further hypothesis and will possibly be having some of their hypotheses confirmed."
"Where did we come from and what happened before? We all have that question inside us."
Image Caption: Fragment of the Murchison meteorite (at right) and isolated individual particles (shown in the test tube). Courtesy United States Department of Energy
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