Tomoko Arai, Recon team, 2nd January 2013, Szabo Bluff
Happy new year to all (^0^)v In contrast to the beautiful weather yesterday and the day before yesterday, it was snowy and windy today. Again, we stayed all day in the tent. Since we only have less than three weeks to go, I hope the weather recovers soon. So far, we (the recon team) have collected thirty three meteorites in total. As a new-year wish for finding more samples, I would like to write a bit about the types of meteorites I am interested in and the reason why. Studies of meteorites have provided basic understanding on extraterrestrial bodies including their origin and evolution, as well as informing ground-based telescopic observations and data from space exploration. Mineralogical, chemical and isotopic data of variable classes of meteorites obtained by laboratory measurements have set a framework for understanding the evolution of the Solar System, although parent bodies for meteorites are generally hard to define except specific meteorite types, such as ones from the Moon and Mars. Accordingly, our current understanding of the Solar System is dependent on the meteorite samples currently available. Yet, the current meteorite collection does not include meteorite types matching the remote sensing data of planetary exploration missions such as those from Venus and Mercury (see the Katie’s blog dated Dec. 27). There are also some meteorites that we have in our collection that originate from small planetary bodies (i.e., proto-planets or asteroids) that experienced melting to form an iron core, a mantle and a crust in a process known as magmatic differentiation, and yet at the present day we cannot well match the particular body from which they were sourced. Additionally there are some other types of meteorites that reveal just one detail of a parent body’s melting and magmatic history, but do not reveal its complete history. These meteorites are known as “ungrouped” or “unclassified” types, because their mineralogy and chemistry do not match any other known type of meteorites – they are unique. Such meteorites are extremely important, providing insights to the diversity of planetary evolution processes in the Solar System. In fact, some of these types of ungrouped meteorites have been found here in the Graves Icefields, i.e., GRA 06128/06129, which were collected during the 2006 ANSMET field season in a locality less than twenty miles away. I do hope that we could possibly encounter such types of ungrouped meteorites, which may lead us to a more complete view of the Solar System history. The picture was taken on the top of Szabo Bluff on December 31st, 2012.