November 21, 2003

Stardust:
Microprobe Analysis of
Pristine Stellar Material

Michael J. Pellin
Group Leader - Senior Scientist
Argonne National Laboratory

The discovery of grains in primitive meteorites that condensed from stellar outflows and survived the interstellar medium has led to a unique new type of astronomy - one that can be done with a microscope rather than a telescope. These refractory grains contain within them a geminate record both of the nucleosynthesis of the star that produced them and of the condensing conditions that led to their formation. This talk will detail their discovery, analysis and point to a few new discoveries based on this new way of studying stars.

Bio Sketch

Dr. Pellin received a B.S. in chemistry from Northwestern University, a Ph.D in physical chemistry from the University of Illinois, and is currently the Associate Division Director responsible for the Materials Chemistry Programs of the Materials Science Division at Argonne National Laboratory. He directs a world class research effort in understanding the surface chemistry of materials that includes operation of the world's most sensitive trace analysis facility. Studies include basic research into the mechanisms of directed energy interactions with surfaces such as sputtering and laser desorption, work to understand optical damage, and the analysis of presolar grains providing insights into stellar nucleosynthesis.

SMSI Minutes
Stardust:Microprobe Analysis of Pristine Stellar Material. 21 Nov. 03

Old friends: Murchisson and Moissanite weren't mentioned in the announcement abstract. SiC Moissanite, the synthetic diamond look alike in 0.5Mn grains was found in Murchison CM2 (1969 fall) which gave a formation history of supernova 92%, and a few percent nova and a 5 stellar mass star. Using Schwarzschild microscopy http://physics.nist.gov/Divisions/Div841/Gp1/schwarzschild.html the Murchisson meteorite. was subjected to One in a Trillion analysis http://chemistry.anl.gov/MSD/One_in_a_trillion.htm. Using one of Michael J. Pellin's home pages http://chemistry.anl.gov./MSD/overview.htm there are links to other aspects of his work and talk.

Respectfully submitted, Stan Schmidt, Recording Secretary