THIS PROPOSAL ADDRESSES THE LARS GOAL OF MAXIMIZING THE STARDUST MISSION SCIENCE RETURN BY DETAILED ANALYSIS OF RETURNED COMET SAMPLES. THE WORK WILL FOCUS ON IMPORTANT SAMPLE ASPECTS REVEALED IN PREVIOUS WORK BUT THAT CLEARLY NEED MORE INTENSIVE STUDY TO PROVIDE CRITICAL DATA ON MATERIALS THAT THAT FORMED COMETS. MOST OF THE WORK WILL BE ANALYSES OF COMET WILD 2 SAMPLES WITH OUR DEDICATED TRANSMISSION ELECTRON MICROSCOPE. A SPECIALTY OF OUR GROUP IS UNIQUE PROCESSING OF AEROGEL TRACKS TO MAXIMIZE THE GRAINS CAN BE FOUND AND EXTRACTED FOR CORRELATED TEM&SIMS COMPOSITIONAL AND ISOTOPIC STUDIES. BECAUSE LARGE PARTICLES AT TRACK ENDS ARE VERY LIMITED WE BELIEVE THAT FUTURE WORK SHOULD EMPHASIZE THE NEARLY UNLIMITED NUMBER OF WELL-PRESERVED SMALL (1-8 M) FRAGMENTS THAT CAN MINED FROM TRACKS. WE HAVE DEMONSTRATED THAT THESE OFTEN OVERLOOKED PARTICLES ARE EXTREMELY VALUABLE AND THEY CAN BE EFFICIENTLY FOUND RECOVERED AND USED FOR HIGH PRECISION OXYGEN ISOTOPE MEASUREMENTS AND TEM STUDIES. WE HAVE WORKED ON>20 WILD 2 TRACKS THAT LED TO MANY SIGNIFICANT DISCOVERIES. THE STUDIES REVEALED IMPORTANT AREAS FOR ADVANCED WORK THAT CAN LARGELY BE DONE WITH SAMPLES IN HAND PLUS A FEW NEW ALLOCATIONS OR INVOLVEMENT IN TRACK CONSORTIA COLLABORATIONS. NEW PROJECTS INCLUDE THE FOLLOWING: A) OLIVINE ORIGIN. WILD 2 OLIVINE IN CHONDRULE FRAGMENTS AND PROBABLE CONDENSATES (MN ENRICHED FO [LIME]&SOLAR-LIKE 16O) ARE COMMON AND WE WILL ESTIMATE THE RATIO OF THESE SOURCES TO CONSTRAIN MODELS FOR THE ORIGIN OF THIS DOMINANT COMETARY MINERAL AND ITS TRANSPORT ACROSS THE NEBULA. EVIDENCE FOR THE IGNEOUS/CONDENSATION RATIO WILL COME FROM STUDIES OF A NUMBER OF PROPERTIES LIKE ADHERING GLASS AND OTHER PHASES ZONING O ISOTOPE COMPOSITION (NOW AT A FEW PERMIL FOR 2 M GRAINS!) METAL INCLUSIONS (INCLUDING PT GROUP NUGGETS) AND MINOR ELEMENT COMPOSITION (CA CR MN AND PERHAPS NI). WE WILL EXPAND OLIVINE O ISOTOPE AND MINOR ELEMENT STUDIES THAT INDICATE WILD 2 OLIVINES WERE DERIVED FROM A BROADER RESERVOIR OF GRAINS THAN FOUND IN SPECIFIC CHONDRITE GROUPS. B) COMET CAIS DIFFER FROM TYPICAL CHONDRITE CAIS. THESE DIFFERENCES WILL BE EXPLORED AND MUCH NEEDED O ISOTOPE DATA WILL BE OBTAINED. NANOPHASE TIN (OFTEN WITH HIGH V) OCCURS IN WILD 2 CAI ANORTHITE&SPINEL AND IDPS BUT NOT IN CHONDRITES IN THE SAME FORM. THEY WILL BE STUDIED IN THE TEM ALONG WITH REFRACTORY PT NUGGETS TO DETERMINE IF THEY ARE EARLY CONDENSATES AND PROVIDE A MEANS OF IDENTIFYING HOST PHASES AS CONDENSATES. TIN IS PREDICTED TO BE A FIRST CONDENSATE WHEN C/O ~ 1. C) WILD 2 OLIVINE CONTAINS LOWER CR THAN 3.00 CHONDRULE OLIVINE. WE WILL DO DETAILED EXAMINATION OF CR IN WILD 2 OLIVINE TO LOOK FOR EITHER EVIDENCE OF METAMORPHIC DIFFUSION OF CR OR THAT THEY FORMED WITH INTRINSICALLY LOWER CR. D) KOSOMOCHLORIC (NA CR-RICH) CLINOPYROXENE +OLIVINE+OTHER PHASES (=KOOL GRAINS) EXIST IN MOST STARDUST TRACKS AND ARE COMMON IN IDPS BUT NOT IN CHONDRITES. SOME ARE ASSOCIATED WITH IGNEOUS MATERIAL BUT THEIR ORIGIN IS A MYSTERY THAT NEEDS TO BE SOLVED PROBABLY BY ASSOCIATION WITH ATTACHED COMPONENTS SUCH AS CHONDRULE FRAGMENTS. E) WE WILL FIND AND STUDY MORE SULFIDE/SILICATE ASSEMBLAGES TO EXPLORE THE PROPOSED IGNEOUS ORIGIN OF SOME OF THEM. F) WE WILL SEARCH THE SMALLEST TRACKS THAT WE BELIEVE ARE OPTIMAL PLACES TO TEST FOR ELEMENTAL ABUNDANCE EVIDENCE OF PRESENCE PRE-IMPACT GEMS (GLASS + NANOMETAL&SULFIDE). STRONG EVIDENCE FOR OR AGAINST GEMS IN COMETS WOULD PROVIDE NEW EVIDENCE FOR GEMS ORIGINS AND WOULD OPEN DISCUSSION ABOUT THE POSSIBILITY OF A HIGHER SURVIVAL RATE OF PRE-SOLAR GRAINS IN WILD 2 PRESENTLY ESTIMATED TO BE ~ 1000 PPM. G) WE FOUND THE ONLY ISOTOPICALLY ANOMALOUS GRAIN IN A STARDUST TRACK AND WILL USE REFINED METHODS TO FIND ENOUGH TO MEASURE THEIR ABUNDANCE AND LINK ISOTOPIC DATA TO TEM ANALYSES. H) WE WILL DO ANALOG STUDIES ON LEAST HEATED GIANT CLUSTER INTERPLANETARY DUST PARTICLES OF PROBABLE COMETARY TO DETERMINE IF WILD 2 COMET IS A REPRESENTATIVE COMET.