Neon and Helium in the Surface of Stardust Cell C2028

Previous studies of light noble gases in Stardust aerogel samples detected a variety of isotopically non-terrestrial He and Ne compositions. However, with one exception, in none of these samples was there visible evidence for the presence of particles that could have hosted the gases. The exception is materials keystoned from track 41, cell C2044, which contained observable fragments of the impacting Wild 2 comet coma grain. Here we report noble gas data from a second aerogel sample in which grains are observed, cut from the surface of a cell (C2028) riddled with tiny tracks and particles that are thought to be secondary in origin, ejected toward the cell when a parent grain collided with the spacecraft structure and fragmented. Interestingly, measured 20Ne/22Ne ratios in the track 41 and C2028 samples are similar, and within error of the meteoritic "Q-phase" Ne composition

Anatomy of a cluster IDP. Part 2: Noble gas abundances, trace element geochemistry, isotopic abundances, and trace organic chemistry of several fragments from L2008#5

The topics discussed include the following: noble gas content and release temperatures; trace element abundances; heating summary of cluster fragments; isotopic measurements; and trace organic chemistry

Light Element Isotopic Compositions of Cometary Matter Returned by the STARDUST Mission

Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild2 particle fragments, however extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Non-terrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is {sup 16}O-enriched like refractory inclusions in meteorites, suggesting formation in the hot inner solar nebula and large-scale radial transport prior to comet accretion in the outer solar system

A Preliminary Light Noble Gas Investigation of Stardust Samples

We have measured the concentrations and isotopic compositions of helium and neon by stepwise pyrolysis in four different Stardust sample types: (a) melted aerogel with embedded particle fragments from the track 41 wall; (b) aerogel adjacent to track 41 without visible particle fragments; (c) individual terminal particles extracted from track 108; (d) “blank” surface aerogel from cell 41. Presented at the 72nd Annual Meeting of the Meteoritical Society, abstract number 5319

Radiation History of Giant Cluster Particle U2-20GCA, a Probable Cometary IDP

Spallation Ne in the giant U2-20GCA cluster IDP suggests exposure to radiation near the early Sun. Mineral chemistry links it to Comet Wild 2 coma grains

Helium and Neon in Stardust Aerogel Samples from Cell 2044 Adjacent to Track 41

We have measured the concentrations and isotopic compositions of He and Ne by stepwise pyrolysis in \u3e20 Stardust cell 2044 aerogel samples adjacent to track 41 and without visible particle fragments. Presented at the 73rd Annual Meeting of the Meteoritical Society, Abstract number 5332

Helium and Neon in Blank STARDUST Aerogel Samples

Helium and neon concentrations and compositions were measured in 49 samples of “blank” aerogel from Stardust cell C2044. Five samples show interesting compositions that if related to the Track 41 impactor indicate a complicated parent particle

Q-Gases in an Unusual IDP: A Noble Gas Link to Carriers in Stardust Track 41

Helium- and neon-isotope ratios in a large amorphous particle extracted from a cluster IDP closely match compositions measured in the meteoritic Q-phase

A Light Noble Gas Inventory of Stardust Cell C2044

Helium and neon concentrations and isotopic compositions from Stardust cell C2044 track 41 and aerogel samples