Summary

Description

<p>This work will establish ultra-clean chemical purification and isotopic analysis of chromium and manganese in sub-milligram-sized astromaterial samples.  Manganese-chromium isotopic analysis can be used to determine the age of ancient (>4.5 billion year old) dust and rock fragments, as well as for mapping in space and time the distribution of primordial material in the protoplanetary disk, in particular during the early accretion period of asteroids.  This laboratory-based research will be coordinated with our microMill sampling facility and state-of-the art Triton thermal ionization mass spectrometer (TIMS).  This work will develop the high precision analysis processes of ultra small samples of the type that will be returned by robotic and, eventually, human exploration missions to asteroids.  We will also integrate microMill sampling, chemical purification, and TIMS analysis of small targeted regions of larger samples (e.g., core and/or rims of minerals contained in rocks returned from differentiated asteroids, the Moon, and/or possibly ancient rocks from Mars). At the completion of this multi-year project ARES scientists will have well-developed, calibrated, and fully-documented sets of: (1) low blank micro-dissolution vessels and (2) of micro-columns to efficiently purify Mn and Cr from future small returned samples, as well as an ultra-clean workspace to conduct these experiments.  In short, we propose to have all sample procedures and laboratory spaces prepared and tested prior to any future Mission-related sample allocation.  This work will strongly enhance the quality of science results obtained from the tiny particles expected to be returned by robotic, and eventually human, exploration missions.</p>