We have investigated spatial and spectral associations between mineral species and organic matter in the Tagish Lake meteorite. Synchrotron‐based infrared microspectroscopy allowed us to spatially locate specific organic and inorganic compounds within multiple Tagish Lake grains with high spatial resolution. Generated two‐dimensional infrared maps present strong spatial association between aliphatic C‐H and OH in phyllosilicates in Tagish Lake grains. These observations indicate possible roles of phyllosilicates for the formation, evolution, and preservation of organic matter. Infared spectra of all studied Tagish Lake grains show a strong carbonate band, which also shows a weak but positive correlation with organic matter in some grains. However, intergrain correlation was not observed between carbonates and organics, which is likely due to the difference of carbonate occurrence, e.g., presence of larger grains or intergrowth of carbonates on phyllosilicates. Possible scenarios further explaining the observed associations of organics with phyllosilicates and carbonates are presented.

Synchrotron-based Fourier transform infrared spectroscopy and Raman spectroscopy are applied with submicrometer spatial resolution to multiple grains of Sutter's Mill meteorite, a regolith breccia with CM1 and CM2 lithologies. The Raman and infrared active functional groups reveal the nature and distribution of organic and mineral components and confirm that SM12 reached higher metamorphism temperatures than SM2. The spatial distributions of carbonates and organic matter are negatively correlated. The spatial distributions of aliphatic organic matter and OH relative to the distributions of silicates in SM2 differ from those in SM12, supporting a hypothesis that the parent body of Sutter's Mill is a combination of multiple bodies with different origins. The high aliphatic CH 2 /CH 3 ratios determined from band intensities for SM2 and SM12 grains are similar to those of IDPs and less altered carbonaceous chondrites, and they are significantly higher than those in other CM chondrites and diffuse ISM objects.

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compared to CO3.4-CO3.6 (20 C), which may indicate that the graphitization and structural ordering of carbon reach a critical temperature regime around petrologic type CO3.3.

The Saric ßic ßek howardite meteorite shower consisting of 343 documented stones occurred on September 2, 2015 in Turkey and is the first documented howardite fall. Cosmogenic isotopes show that Saric ßic ßek experienced a complex cosmic-ray exposure history, exposed during~12-14 Ma in a regolith near the surface of a parent asteroid, and that añ 1 m sized meteoroid was launched by an impact 22 AE 2 Ma ago to Earth (as did one-third of all HED meteorites). SIMS dating of zircon and baddeleyite yielded 4550.4 AE 2.5 Ma and 4553 AE 8.8 Ma crystallization ages for the basaltic magma clasts. The apatite U-Pb age of 4525 AE 17 Ma, K-Ar age of~3.9 Ga, and the U,Th-He ages of 1.8 AE 0.7 and 2.6 AE 0.3 Ga are interpreted to represent thermal metamorphic and impact-related resetting ages, respectively. Petrographic; geochemical; and O-, Cr-, and Ti-isotopic studies confirm that Saric ßic ßek belongs to the normal clan of HED meteorites. Petrographic observations and analysis of organic material indicate a small portion of carbonaceous chondrite material in the Saric ßic ßek regolith and organic contamination of the meteorite after a few days on soil. Video observations of the fall show an atmospheric entry at 17.3 AE 0.8 km s À1 from NW; fragmentations at 37, 33, 31, and 27 km altitude; and provide a pre-atmospheric orbit that is the first dynamical link between the normal HED meteorite clan and the inner Main Belt. Spectral data indicate the similarity of Saric ßic ßek with the Vesta asteroid family (V-class) spectra, a group of asteroids stretching to delivery resonances, which includes (4) Vesta. Dynamical modeling of meteoroid delivery to Earth shows that the complete disruption of ã 1 km sized Vesta family asteroid or a~10 km sized impact crater on Vesta is required to provide sufficient meteoroids ≤4 m in size to account for the influx of meteorites from this HED clan. The 16.7 km diameter Antionia impact crater on Vesta was formed on terrain of the same age as given by the 4 He retention age of Saric ßic ßek. Lunar scaling for crater production to crater counts of its ejecta blanket show it was formed~22 Ma ago.A field expedition to the area was conducted by the

The Didim meteorite contains multiple lithologies and clasts of different petrologic types in a single stone. A mixture of H5 clasts in an unequilibrated H3 host was previously observed in Didim, according to the initial characterization reported in the Meteoritical Bulletin Database, providing an opportunity to investigate molecular composition that contains varying degree of equilibrium with varying mineralogy. We have taken a "from large scale to small scale" approach to spectroscopically investigate the chemical content of Didim. Centimeter-scale biconical reflectance spectra show that Didim contains abundant olivine, pyroxene, and other optically active minerals, evident from a strong Band I near 0.93 µm and a weak Band II near 1.75 µm. Micrometer-scale Raman spectroscopic investigations reveal the presence of carbonaceous material in addition to forsteritic olivine, pyroxene (augite and enstatite), feldspars, and opaque phases such as chromite and hematite. 3-D Raman tomographic imaging shows that the carbonaceous material near chondrules extends underneath a large olivine grain, going further down toward the interior, indicating that the observed carbonaceous matter is likely indigenous. Nano-scale infrared measurements reveal that the observed chemical materials in Didim contain spectral, and therefore, molecular, variations at the~20 nm spatial scale. These chemical variations are normally not accessible via conventional infrared techniques, and indicate the presence of different cations in the molecular composition of observed minerals. By taking the "large scale to small scale" approach, we show that these compositional variations can be captured and investigated nondestructively in meteorites to understand formation/evolution of chemical components in the parent body.

Meteorites contain organic matter that may have contributed to the origin of life on Earth. Carbonyl compounds such as aldehydes and carboxylic acids, which occur in meteorites, may be precursors of biologically necessary organic materials in the solar system. Therefore, such organic matter is of astrobiological importance and their detection and characterization can contribute to the understanding of the early solar system as well as the origin of life. Most organic matter is typically sub-micrometer in size, and organic nanoglobules are even smaller (50–300 nm). Novel analytical techniques with nanoscale spatial resolution are required to detect and characterize organic matter within extraterrestrial materials. Most techniques require powdered samples, consume the material, and lose petrographic context of organics. Here, we report the detection of nanoglobular aldehyde and carboxylic acids in a highly primitive carbonaceous chondrite (DOM 08006) with ~ 20 nm spatial resolution using nano-FTIR spectroscopy. Such organic matter is found within the matrix of DOM 08006 and is typically 50–300 nm in size. We also show petrographic context and nanoscale morphologic/topographic features of the organic matter. Our results indicate that prebiotic carbonyl nanoglobules can form in a less aqueous and relatively elevated temperature-environment (220–230 °C) in a carbonaceous parent body.

Relationships between organic molecules and inorganic minerals are investigated in a single 34 lm diameter grain of the CR2 chondrite Northwest Africa 852 (NWA) 852 with submicron spatial resolution using synchrotron-based imaging micro-FTIR spectroscopy. Correlations based on absorption strength for the various constituents are determined using statistical correlation analysis. The silicate band is found to be correlated with the hydration band, and the latter is highly correlated with stretching modes of aliphatic hydrocarbons. Spatial distribution maps show that water+organic combination, silicate, OH, and C-H distributions overlap, suggesting a possible catalytic role of phyllosilicates in the formation of organics. In contrast, the carbonate band is anticorrelated with water+organic combination, however uncorrelated with any other spectral feature. The average ratio of asymmetric CH 2 and CH 3 band strengths (CH 2 /CH 3 = 2.53) for NWA 852 is similar to the average ratio of interplanetary dust particles (~2.40) and Wild 2 cometary dust particles (2.50), but it significantly exceeds that of interstellar medium objects (~1.00) and several aqueously altered carbonaceous chondrites (~1.40). This suggests organics of similar length/ branching, and perhaps similar formation regions, for NWA 852, Wild 2 dust particles, and interplanetary dust particles. The heterogeneous spatial distribution of ratio values indicates the presence of a mixture of aliphatic organic material with different length/branching, and thus a wide range of parent body processes, which occurred before the considered grain was formed.