Scott Messenger

Blue22 Software

We have established analytical procedures for quantitative rare earth element (REE) measurements by NanoSIMS 50L ion microprobe with 2–10 μm spatial resolution. Measurements are performed by multidetection using energy filtering under several static magnetic field settings. Relative sensitivity factors and REE oxide/REE element secondary ion ratios...

We report the chemical and structural analysis of nine presolar silicate grains and one presolar oxide grain from the ungrouped chondrite Acfer 094 and the CR chondrite Queen Alexandra Range 99177. Oxygen isotopic analyses indicate that five of these grains condensed in the outflows of asymptotic giant branch (AGB) stars, four have supernova (SN) o...

An interplanetary dust particle contains a submicrometer crystalline silicate aggregate of probable supernova origin. The grain has a pronounced enrichment in 18O/16O (13 times the solar value) and depletions in 17O/16O (one-third solar) and 29Si/28Si (<0.8 times solar), indicative of formation from a type II supernova. The aggregate contains olivi...

A coordinated TEM and NanoSIMS isotopic imaging study of microtome sections of three anhydrous interplanetary dust particles (IDPs) revealed a diverse collection of primitive materials having disparate origins and histories. Presolar silicate grains that likely originated in asymptotic giant branch (AGB) stars were present in each IDP at abundances...

GEMS (Glass with Embedded Metal and Sulfides) grains found in interplanetary dust particles are considered one of the most primitive materials in the Solar System, yet questions remain on how they formed. It has been suggested that GEMS grains are products of radiation processing and amorphization of sulfide and silicate mineral grains in the inter...

To characterize the ATLO (Assembly, Test, and Launch Operations) environment of the OSIRIS-REx spacecraft, we analyzed 17 aluminum witness foils and two blanks for bacterial, archaeal, fungal, and arthropod DNA. Under NASA's Planetary Protection guidelines, OSIRIS-REx is a Category II outbound, Category V unrestricted sample return mission. As a re...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Projectiles striking the Moon have modified its crust and delivered volatile elements to its interior and surface. Direct evidence of impactor origins is recorded by the rare occurrence of sub-cm sized meteorite fragments identified in Apollo samples and lunar meteorites. The Bench Crater meteorite is a millimetre-sized carbonaceous chondrite colle...

We built a collector to filter interplanetary dust particles (IDPs) larger than 5 μm from the clean air at the Amundsen Scott South Pole station. Our sampling strategy used long duration, continuous dry filtering of near‐surface air in place of short duration, high‐speed impact collection on flags flown in the stratosphere. We filtered ~10⁷ m³ of c...

The abundance and distribution of water within Mars through time plays a fundamental role in constraining its geological evolution and habitability. The isotopic composition of Martian hydrogen provides insights into the interplay between different water reservoirs on Mars. However, D/H (deuterium/hydrogen) ratios of Martian rocks and of the Martia...

We carried out a coordinated mineralogical and isotopic study of a Wark-Lovering (WL) rim on a Ca,Al-rich inclusion (CAI) from the reduced CV3 chondrite Vigarano. The outermost edge of the CAI mantle is mineralogically and texturally distinct compared to the underlying mantle that is composed of coarse, zoned melilite (Åk∼10-60) grains. The mantle...

Novel Applications of Focused Ion Beam Technique for Planetary Sample Analyses - Volume 24 Supplement - Z. Rahman, L. P. Keller, A. N. Nguyen, M. S. Thompson, Scott R. Messenger

Coordinated Microanalysis of Phosphates in High-Titanium Lunar Basalts - Volume 24 Supplement - J. J. Barnes, M. S. Thompson, F. M. McCubbin, J. Y. Howe, Z. Rahman, S. Messenger, T. Zega

The Comet Astrobiology Exploration Sample Return (CAESAR) mission is one of two finalists selected by NASA for Phase A study in the New Frontiers program. CAESAR will acquire a minimum of 80 g of material from the surface of comet 67P/Churuyumov-Gerasimenko and return it to Earth for laboratory analysis. CAESAR preserves much of the science of a cr...

Water-Rock Interactions in Outer Solar System Bodies: Evidence from the Coordinated Analysis of Interplanetary Dust - Volume 24 Supplement - Lindsay P. Keller, Christopher Snead, Scott Messenger, George J. Flynn, Sue Wirick

The δ³⁷Cl from different generations of apatite in martian meteorite Chassigny has a range of ≈10‰ and is almost as great as measurements made on all martian meteorites (≈14‰). This range represents the mixing of distinct Cl isotope reservoirs during the formation of Chassigny: (1) an isotopically light-Cl mantle reservoir (δ³⁷Cl = −4 to −6‰) that...

Asteroid (162173) Ryugu is the target object of Hayabusa2, an asteroid exploration and sample return mission led by Japan Aerospace Exploration Agency (JAXA). Ground-based observations indicate that Ryugu is a C-type near-Earth asteroid with a diameter of less than 1 km, but the knowledge of its detailed properties is still very limited. This paper...

CAESAR will collect at least 80 g of surface sample from the smooth terrain on the nu- cleus of comet 67P/Churyumov-Gerasimenko, and return it to Earth. The system protects both volatile and non-volatile components from con- tamination or alteration that would hamper their scientific analysis.

OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This manuscript describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the O...

We have discovered in a Stardust mission terminal particle a unique mineralogical assemblage of symplectically intergrown pentlandite ((Fe,Ni)9S8) and nanocrystalline maghemite (γ-Fe2O3). Mineralogically similar cosmic symplectites (COS) have only been found in the primitive carbonaceous chondrite Acfer 094 and are believed to have formed by aqueou...

Transmission electron microscope examination of more than 250 fragments, >1 μm from comet Wild 2 and a giant cluster interplanetary dust particle (GCP) of probable cometary origin has revealed four new calcium-aluminum-rich inclusions (CAIs), an amoeboid olivine aggregate (AOA), and an additional AOA or Al-rich chondrule (ARC) object. All of the CA...

In May of 2011, NASA selected the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) asteroid sample return mission as the third mission in the New Frontiers program. The other two New Frontiers missions are New Horizons, which explored Pluto during a flyby in July 2015 and is on its way for a fly...

Corundum-bearing Ca-Al-rich inclusions (CAIs) are a rare class of high-temperature condensates from the inner regions of the protoplanetary disk. Their mineralogy is intermediate between isolated corundum grains and CAIs where corundum has been replaced by lower-temperature phases. These inclusions sample a critical transitional period of the inner...

Chondritic planetesimals are among the first planetary bodies that accreted inside and outside water snow line in the protoplanetary disk. CV3 carbonaceous chondrite parent body accreted relatively small amount of water ice, probably near the snow line, and experienced water-assisted metasomatic alteration that resulted in formation of diverse seco...

Collecting cosmic dust is a tricky business! Despite Earth's surface being showered by thousands of tons of comic dust every year, such dust is quickly lost in a sea of terrestrial particles. Finding the tiny cosmic treasures requires collecting dust from the cleanest environments where the terrestrial particle background is low. The stratosphere c...

Interplanetary dust particles (IDPs) collected in the Earths stratosphere derive from collisions among asteroids and by the disruption and outgassing of short-period comets. Chondritic porous (CP) IDPs are among the most primitive Solar System materials. CP-IDPs have been linked to cometary parent bodies by their mineralogy, textures, C-content, an...

We performed chemical, mineralogical, and isotopic studies of the first interplanetary dust particles (IDPs) collected in the stratosphere without the use of silicone oil. The collection substrate, polyurethane foam, effectively traps impacting particles, but the lack of an embedding medium results in significant particle fragmentation. Two dust pa...

We describe a Ca,Al-rich inclusion in the Vigarano CV3 chondrite that records diverse oxygen isotope compositions.

Na, K-rich around a chondrule in a low petrographic type UOC LEW 86018 (L3.1) is being studied to understand the metamorphism, metasomatism in UOCs.

To evaluate 3D nano structure of GEMS correctly, we performed complete TEM-tomography. Many GEMS grains were observed to be aggregated into clusters.

A 4 × 6 μm terminal particle from Stardust track 130, named Bidi, is composed of a refractory assemblage of Fo97 olivine, Al- and Ti-bearing clinopyroxene and anorthite feldspar (An97). Mineralogically, Bidi resembles a number of components found in primitive chondritic meteorites including Al-rich chondrules, plagioclase-bearing type I ferromagnes...

Carbonaceous matter on the surfaces of black pyroclastic beads, collected from Shorty crater during the Apollo 17 mission, represents the first identification of complex organic material associated with any lunar sample. We report the chemical, physical and isotopic properties of this organic matter that together support a pre-terrestrial origin. W...

We conducted multi-element isotopic analyses of 11 presolar silicate grains from the Acfer 094 meteorite having unusual O isotopic compositions. Eight grains are 18O-rich, one is 16O-rich, and two are extremely 17O-rich. We constrained the grains' stellar sources by measuring their Si and Mg isotopic ratios, and also the 54Fe/56Fe and 57Fe/56Fe rat...

We conducted experiments in space to investigate the aggregation of millimeter- and submillimeter-sized particles in microgravity, an important early step in planet formation. Particulate materials included salt (NaCl), sugar (sucrose), coffee, mica, ice, Bjurböle chondrules, ordinary and carbonaceous chondrite meteorite fragments, and acrylic and...

Chronologically-relevant Mg-isotope data are presented for a chondrule bearing the only known natural occurrences of wassonite, ideally stoichiometric TiS.

We have discovered a unique presolar grain in an IDP consisting of a crystalline spinel core and glassy silicate mantle.

We present results of the first coordinated in situ isotopic and chemical mapping of the Bells meteorite using a newly developed two-step laser mass spectrometer.

NASA's OSIRIS-REx mission will return samples of asteroid Bennu in 2023. We review our approach to unraveling the history of Bennu by returned sample analyses.

Ancient halite grains are found in some H-chondrite meteorites, but these halites are exogenous to H chondrites. The original halite parent body (HaPB) must have been warm, wet, and organic-rich. The dwarf planet Ceres has been proposed as the HaPB.

We analyzed carbonaceous materials in the two main morphological types of Stardust tracks (A, and B). We analyzed 71 particles (∼1–10 μm in size) distributed along these tracks with transmission electron microscopy (TEM) and found carbon associated with 16 of them. The carbonaceous materials occur in five distinct morphologies: graphitic, smooth, d...

CM chondrite Bench Crater meteorite was found in Apollo 12 regolith. We report H, C and N isotope data, and discuss implications for delivery of volatiles to the Moon.

Here we present oxygen isotope results for the core and Wark-Lovering rim of a mass dependently fractionated CAI.

A Wark-Lovering rim shows a multi-stage formation history with nebular reservoirs.

We investigate the hypothesis that halites in the H chondrites Zag and Monahans originate from Ceres. Evidence includes mineralogy of the halites and orbital simularities between 1 Ceres and the purported H chondrite parent body 6 Hebe.

This report focuses on coordinated analyses of indigenous crystalline and amorphous/melt Wild-2 materials along the aerogel track walls, their interaction with aerogel during collection and comparisons with their terminal particles.

We report C/N ratios, and other properties of two chondritic porous IDPs and a Concordia fluffy micrometeorite.

We report in situ analyses of organic nanoglobules in the Sutter’s Mill meteorite using UV fluorescence imaging, FTIR, STEM, NanoSIMS, and uL2MS.

TEM analysis of a presolar AGB silicate from QUE 99177 reveals a small nanocrystalline enstatite core surrounded by an amorphous Fe-bearing pyroxene-like shell.

We conduct an extensive search for large presolar silicates to enable multi-element isotopic analyses and mineralogical studies of single grains. This will greatly constrain the stellar origins, condensation conditions, and nucleosynthetic processes.

Using a laser microprobe instrument equipped with a new vacuum ultraviolet laser ionization source we have been able to map in situ the distribution of organic matter in fresh fracture surfaces of carbonaceous chondrites.

We present coordinated transmission electron microscopy and nitrogen isotopic measurements of the carbonaceous material in an IDP collected without the use of silicone oil.

Here we present petrography and isotopic data for ultrarefractory CAIs, including a rare example of a hibonite core with corundum rim - the reverse of the mineral sequence predicted for condensation from a cooling gas of solar composition.

We report the mineralogy and oxygen isotope compositions of two hydrated, carbon-rich interplanetary dust particles.

We are exploring the nature of mineral-organic associations through coordinated analyses of their chemistry, mineralogy, spectroscopy and isotopic characteristics. Here we report our mineralogical observations.

of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Amorphous silicates in CR 3.0 chondrites and Acfer 094 are compared and contrasted with GEMS grains in IDPs. Parent body oxidation and hydration reactions have modified the meteoritic amorphous silicates.

We report initial mineralogical and chemical studies of interplanetary dust particles collected in the stratosphere using a polyurethane foam substrate, without the use of silicone oil.

We report the mineralogical characterization by transmission electron microscopy (TEM) of two presolar O-rich grains that have different stellar origins.

Microprobe two-step laser mass spectrometry utilizing a novel vacuum UV photoionization source has been applied to mapping the spatial distribution of organic species in carbonaceous chondrite matrices at micron spatial resolutions.

Abstract– Coordinated in situ transmission electron microscopy and isotopic measurements of carbonaceous phases in interplanetary dust particles were performed to determine their origins. Five different types of carbonaceous materials were identified based on their morphology and texture, observed by transmission electron microscopy: globular, vesi...

Analyses of samples returned from Comet 81P/Wild-2 by the Stardust spacecraft have resulted in a number of surprising findings that show the origins of comets are more complex than previously suspected. However, these samples pose new experimental challenges because they are diverse and suffered fragmentation, thermal alteration, and fine scale mix...

Wassonite, ideally stoichiometric TiS, is a titanium monosulfide not previously observed in nature, that was discovered within the Yamato 691 EH3 enstatite chondrite. Twelve Ti-S phase grains were identified in a rare barred olivine (BO) chondrule; three of the grains were extracted by the focused ion beam technique. Because of the submicrometer si...

Introduction: Most achondrites experienced secondary processes after their formation such as shock and thermal meta-morphism, brecciation, melting, and metasomatism. These secondary events hamper the understanding of geologic history of the parent body. Thus, it is important to understand the mechanism of secondary disturbance of textures, bulk che...

The Comment by Bradley challenges our chemical and isotopic measurements of GEMS grains, arguing that pervasive infiltration of silicone oil and sample heating undermine our comparisons with equally uncertain interstellar grain compositions. However, we have already shown that such effects are negligible and cannot account for the extraordinary che...

Abstract– We have developed new sample preparation and analytical techniques tailored for entire aerogel tracks of Wild 2 sample analyses both on “carrot” and “bulbous” tracks. We have successfully ultramicrotomed an entire track along its axis while preserving its original shape. This innovation allowed us to examine the distribution of fragments...

Abstract– Recent spacecraft missions to comets have reopened a long-standing debate about the histories and origins of cometary materials. Comets contain mixtures of anhydrous minerals and ices seemingly unaffected by planetary processes, yet there are indications of a hydrated silicate component. We have performed aqueous alteration experiments on...