The PPOSS (Planetary Protection of Outer Solar System bodies) project, coordinated by
the European Science Foundation was selected by the European Commission in August 2015
following the Horizon 2020 call `Space-Competitiveness of the European Space Sector-2015'.
In addition to the European Science Foundation, DLR, COSPAR, Imperial College London,
EUROSPACE, INAF and Space Technology Ireland Ltd. are also part of the project consortium
and PPOSS also has several international partners and observers.
PPOSS will run for three years (2016-2018) and has for main objectives to provide an interna-
tional forum to consider and approach the specificity of Planetary Protection (biological and
organic contamination) for outer Solar system bodies, including icy worlds and small bodies,
in the general context of Planetary Protection regulation.
While significant effort has been, and is being provided to address planetary protection in the
context of the exploration of inner Solar System bodies, and in particular Mars, PPOSS would
allow to tackle the scientific, technological and policy-making specificity of Planetary Protection
of outer solar system bodies. Project findings will be considered in the general context of the
international planetary protection landscape and presented to COSPAR PPP...
How complex carbonaceous molecules in space are, what their abundance is and on what timescales they form are crucial questions within cosmochemistry. Despite the large heterogeneity of galactic and interstellar regions the organic chemistry in the universe seems to follow common pathways. The largest fraction of carbon in the universe is incorporated into aromatic molecules (gaseous polycyclic aromatic hydrocarbon as well as solid macromolecular aromatic structures). Macromolecular carbon constitutes more than half of the interstellar carbon, approximately ∼80% of the carbon in meteorites, and is likely to be present in comets. Molecules of high astrobiological relevance such as N-heterocycles, amino acids and pre-sugars have all been identified in trace quantities (ppb) in extracts of carbonaceous meteorites. Their presence in inter- and circumstellar regions is either unknown or contentious. In any event such fragile species are easily destroyed by UV radiation, shocks and thermal processing and are unlikely to survive incorporation into Solar System material without some degradation. The more refractory material, in particular macromolecular carbon may retain an interstellar heritage more faithfully. We present laboratory measurements on the photostability of organic compounds and discuss their survival in regions with elevated UV radiation. We also show recent observations of diffuse interstellar bands indicating the presence of fullerenes. We investigate the link between the carbon chemistry in interstellar space and in the Solar System by analyzing the carbonaceous fraction of meteorites and by reviewing stable isotopic data. It also seems evident that both volatile and refractory material from carbonaceous meteoritic has been substantially altered owing to thermal and aqueous processing within the Solar System.
Past life on Mars will have generated organic remains that may be preserved in present day Mars rocks. The most recent period in the history of Mars that retained widespread surface waters was the late Noachian and early Hesperian and thus possessed the potential to sustain the most evolved and widely distributed martian life. Guidance for investigating late Noachian and early Hesperian rocks is provided by studies of analogous acidic and sulfur-rich environments on Earth. Here we report organic responses for an acid stream containing acidophilic organisms whose post-mortem remains are entombed in iron sulphates and iron oxides. We find that, if life was present in the Hesperian, martian organic records will comprise microbial lipids. Lipids are a potential sizeable reservoir of fossil carbon on Mars, and can be used to distinguish between different domains of life. Concentrations of lipids, and particularly alkanoic or “fatty” acids, are highest in goethite layers that reflect high water-to-rock ratios and thus a greater potential for habitability. Goethite can dehydrate to hematite, which is widespread on Mars. Mars missions should seek to detect fatty acids or their diagenetic products in the oxides and hydroxides of iron associated with sulphur-rich environments.
In order to estimate the ability of biochar to sequester carbon as part of greenhouse gas removal technology, there is a need for rapid and accessible estimations of biochar stability. This study employs a novel method using Fourier transform infrared spectroscopy (FTIR) to predict common stability indicators, namely H:C and O:C molar ratios. Biochars derived from barley straw were produced at temperatures from 150 to 700 °C. The greatest compositional changes of the biochars occurred between 200 and 400 °C. All biochars produced at ≥400 °C achieved H:C < 0.7 and O:C < 0.4, indicative of biochars suitable for soil application. Regression models were built using FTIR data to predict H:C and O:C molar ratios. The H:C model produced a coefficient of determination (
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