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Paris: The slightly altered, slightly metamorphosed CM that bridges the gap between CMs and Cos
A fresh, 1.3 kilo stone was found in Paris. It is a CM chondrite with metal, Fe-sulfide, FeS-rich PCPs and relict mesostasis and is ~3.0 ± 0.1. Petrographic and oxygen isotope evidence indicates that it has affinities with the CO chondrites
Light noble gas composition of different solar wind regimes: results from genesis
The Genesis mission provided samples of solar wind
(SW) from different regions on the Sun. These SW regime samples are
important in understanding fractionation processes upon formation and
acceleration of the SW to ultimately deduce solar composition from SW
values. We present He and Ne isotopic and elemental compositions of the
bulk SW (SW of entire collection period) and the 3 major SW regimes: slow
(from the ecliptic plane, emanating from above streamers), fast (emanating
from coronal holes), and coronal mass ejections (CME). At the conference
we will also present Ar data
Mass-fractionation induced by the Genesis solar wind concentrator: Analysis of neon isotopes by UV laser ablation
The solar wind (SW) concentrator, a key instrument onboard the
Genesis mission, was designed to provide larger fluences of implanted SW
for precise isotope analyses of oxygen and nitrogen [1]. SW ions in the mass
range 4–28 amu were accelerated and focused on a “concentrator target” by
an electrostatic mirror. This concentration process caused some instrumental
mass fractionation of the implanted SW ions as function of the radial position
on the target. Correction of this fractionation will be based on a combination
of the measured radial fractionation of Ne isotopes with results of simulations
of the implantation process using the actual performance of the concentrator
and the SW conditions during exposure. Here we present He and Ne
abundance and Ne isotopic composition data along one arm of the gold cross
that framed the 4 concentrator subtargets
Solar neon released from Genesis aluminum collector duriung stepped uv-laser extraction and step-wise pyrolysis
Earlier this year we reported results of UV-laser stepped raster extractions of Ne and He from Genesis' Al-collector [l]. Since then, using pyrolysis of a 0.005 cm^2 fragment of this material left from the earlier study, we have estimated the efficiency of the UV-laser extraction to be at least 95%. We also analyzed Ne released from the Al-collector by means of stepped pyrolysis. Here we compare these new data with stepped UV-laser extraction and the CSSE results [2]. Figure 1 shows the ^(20)Ne/^(22)Ne ratio extracted from Genesis collectors using these three techniques
Argon and neon in Genesis aluminum-coated sapphire collectors from regime arrays
Here we report Ar results from the aluminum on sapphire (AloS) bulk regime samples, from which Ne results were obtained [1]. Ar measurements from other regimes are in progress
Byrd ice core debris constrains the sediment provenance signature of central West Antarctica
Provenance records from sediments deposited offshore of the West Antarctic Ice Sheet (WAIS) can help identify past major ice retreat, thus constraining ice-sheet models projecting future sea-level rise. Interpretations from such records are, however, hampered by the ice obscuring Antarctica's geology. Here, we explore central West Antarctica's subglacial geology using basal debris from within the Byrd ice core, drilled to the bed in 1968. Sand grain microtextures and a high kaolinite content (∼38–42%) reveal the debris consists predominantly of eroded sedimentary detritus, likely deposited initially in a warm, pre-Oligocene, subaerial environment. Detrital hornblende 40Ar/39Ar ages suggest proximal late Cenozoic subglacial volcanism. The debris has a distinct provenance signature, with: common Permian-Early Jurassic mineral grains; absent early Ross Orogeny grains; a high kaolinite content; and high 143Nd/144Nd and low 87Sr/86Sr ratios. Detecting this “fingerprint” in Antarctic sedimentary records could imply major WAIS retreat, revealing the WAIS's sensitivity to future warming
ANALOGUE SAMPLES IN AN EUROPEAN SAMPLE CURATION FACILITY - THE EURO-CARES PROJECT.
The objective of the H2020-funded EURO-CARES project (grant agreement n° 640190) was
to create a roadmap for the implementation of a European Extraterrestrial Sample Curation
Facility (ESCF) that would be suitable for the curation of samples from all possible return
missions likely over the next few decades, i.e. from the Moon, asteroids and Mars.
The return of extraterrestrial samples brought to Earth will require specific storage conditions
and handling procedures, in particular for those coming from Mars. For practical reasons
and sterility concerns it might be necessary for such a facility to have its own collection of
analogue samples permitting the testing of storage conditions, and to develop protocols for
sample prepartion and analyses. Within the framework of the EURO-CARES project, we havecreated a list of the different types of samples that would be relevant for such a curation facility.
The facility will be used for receiving and opening of the returned sample canisters, as well as for
handling and preparation of the returned samples. Furthermore, it will provide some analysis
of the returned samples, i.e. early sample characterisation, and is expected to provide longterm storage of the returned samples. Each of these basic functions requires special equipment.
Equipment, handling protocols and long-term storage conditions will strongly depend on the
characteristics of the materials, and on whether returned samples are from the Moon, Mars or
an asteroidal body. Therefore the different types and aspects of analogue samples one need to
be considered, i.e. the nature of the materials, which analogues are needed for what purpose,
what mass is needed, and how should the analogue samples be stored within the facility.
We distinguished five different types of anologue samples: analogue (s.s.), witness plate, voucher
specimen, reference sample, and standard. Analogues are materials that have one or more physical or chemical properties similar to Earth-returned extraterrestrial samples. Reference samples
are well-characterised materials with known physical and chemical properties used for testing.
They may not necessarily be the same materials as the analogues defined above. Standards are
internationally recognised, homogeneous materials with known physical and chemical properties
that are used for calibration. They can also be used as reference samples in certain circumstances. They may be made of natural materials but are often produced artificially. A voucher
specimen is a duplicate of materials used at any stage during sample acquisition, storage, transport, treatment etc., e.g. spacecraft materials (including solar panels), lubricants, glues, gloves,
saws, drills, and others. In addition, Earth landing site samples (from the touch down site)
would be necessary in case of doubtful analysis, even if normally this type of contamination
is not expected. Finally, a witness plate is defined as material left in an area where work is
being done to detect any biological, particulate, chemical, and/or organic contamination. It is
a spatial and temporal document of what happens in the work area.
Analogue materials could be solids (including ices), liquids or gases. These could contain
biological (extant and/or exinct) and/or organic components. They could be natural materials,
e.g. rocks or minerals, or could be manufactured, such as mixtures of different components,
which may be biologically and/or organically doped. Analogues with appropriate sample size
and nature will be well-suited for testing and training of sample handling procedures, and
for transport protocols. The training of science and curation teams also requires reference
samples and standards. Long-term storage needs special witness plates and voucher specimes.
Developing and testing sample preparation protocols needs all sample types
CI chondrites - Piralla
This provides the SIMS files related to the paper entitled "Primordial water and dust of the Solar System:
Insights from in-situ oxygen measurements of CI chondrites" by Maxime Piralla, Yves Marrocchi, Maximilien J. Verdier-Paoletti, Lionel G. Vacher, Johan Villeneuve, Laurette Piani, David V. Bekaert and Matthieu Gounelle
CI chondrites - Piralla
This provides the SIMS files related to the paper entitled "Primordial water and dust of the Solar System:
Insights from in-situ oxygen measurements of CI chondrites" by Maxime Piralla, Yves Marrocchi, Maximilien J. Verdier-Paoletti, Lionel G. Vacher, Johan Villeneuve, Laurette Piani, David V. Bekaert and Matthieu Gounelle
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