|
Historical Meteorites |
|
|
|
Historical Meteorites |
|
|
|
|
The Murchison meteorite fell at 10:45 am and was accompanied by a loud detonation and a hissing noise. About 100 kg were collected and the strewn field covers about 33 kilometers. Murchison has a shock stage of S1-2. It is an extremely rare type of meteorite. It's high water content, approximately 10 to 12%, suggests that it is cometary in origin. It is very primitive and has undergone very little, if any, alteration since the formation of the solar system about 4.5 billion years ago. Indeed, analysis of Comet Hyakutake has shown a very similar chemical makeup between it and the Murchison meteorite. Interestingly, more than 92 different amino acids have been identified within the Murchison meteorite but only nineteen of these amino acids are found on Earth; the remaining amino acids have no apparent terrestrial source. Thus, murchison provides evidence that organic materials were either preserved from interstellar processes, or actually produced in the solar nebula. Stable isotope analyses, especially of deuterium, carried out on these organic compounds suggest that they are closely related to the organic compounds observed in interstellar clouds; however, some of the meteorite compounds, such as the amino acids, may have been formed from interstellar precursors after their incorporation into solar system objects. Murchison also contains presolar diamonds in concentrations of 1000 ppm, along with grains of graphite and silicon carbide produced during nucleosynthesis in carbon stars. These presolar grains, along with aluminum oxide, spinel, and silicon nitride, are remnants of the presolar dust cloud from which our solar system was formed.
Murchison is one of the most studied
meteorites and one of the most sought after by collectors! |
