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There is evidence from the near‐infrared observations of space missions of the presence of carbonates on the surface of several ocean worlds. However, their genesis remains unresolved. We investigate the hypothesis that these carbonates may be in the form of clathrites assuming that clathrate hydrates are stable phases in the crust and ocean of these ocean worlds. In order to support this, we studied a sample of a potential clathrite from the Hydrate Ridge cold seep (Cascadia Subduction Zone), the carbonate rock fossil of clathrate hydrates, as a terrestrial analogue. We characterised the mineralogy and texture of the sample by using a coupled confocal Raman microscope and scanning electron microscopy instrument with the aim of identifying possible geo‐ and biosignatures, which could be relevant for future missions of exploration to ocean worlds and Mars. Our results show that aragonite is the dominant mineral phase in the clathrite sample, but Mg‐calcite and dolomite were also identified. These three carbonates constitute a pattern related to clathrate hydrate formation and dissociation processes. Dolomite was defined as a biosignature of gas hydrate microbiomes because it was integrated within Mg‐calcite grains precipitated after clathrate hydrate dissociation. Nevertheless, no spectral changes were observed in Raman bands of carbonate minerals that would indicate the influence of clathrate hydrates in their genesis. We also observed that Raman band positions of the associated framboidal pyrites are a characteristic signature of the associated framboid‐like texture because its potential as biosignature may only be attributed by biochemical analysis. [ABSTRACT FROM AUTHOR]

JAXA's upcoming MMX (Martian Moons eXploration) mission will deliver a small rover to Phobos, to explore its surface complementary to the MMX orbiter and the sample return lander. On board this rover is a Raman spectrometer, the RAX Instrument (RAman Spectrometer for MMX), a payload to science. RAX has been designed for being capable to analyze the mineral composition of the Phobos' surface, in order to help reveal the nature and distribution of materials on the surface and ultimately the origin and evolution of the moon. Attached to MMX spacecraft, with direct view from the RAX instrument, a polyethylene terephthalate (PET) target will be placed for on‐ground and during cruise, spectral instrument performances verification, before the MMX rover is released and dropped to the Phobos surface for developing its scientific tasks. A novel deuterated PET material was proposed as verification target (VT) to check the spectral instrument performances. INTA‐CAB developed, manufactured and qualified for the MMX‐RAX space mission, 13 mm diameter and 2‐mm thick pellets of this material, which incorporates two relevant improvement characteristics: reduction in fluorescence and additional Raman bands with regard to ordinary PET used with this purpose. The material was selected as RAX VT and delivered to DLR for performance tests and later integration into the MMX rover together with the RAX flight model. The RAX VT will be critical to check the instrument performances during the several months cruise phase after launch and just before its landing on Phobos surface. This paper reports the development and characterization of the deuterated PET. [ABSTRACT FROM AUTHOR]

The Raman Laser Spectrometer (RLS) is one of three key analytical instruments incorporated within the body of the ExoMars 2022 rover. The rover will collect samples from different sites on the Oxia Planum plain, using a drill capable of penetrating the near subsurface and rocky outcrops to a depth of 2 m. Samples are passed to the Analytical Laboratory Drawer (ALD) in the heart of the rover vehicle, where the Sample Preparation and Distribution System (SPDS) processes and transports the crushed material into a refillable container (RC), which is then presented to the analytical instruments for exobiology and geological investigation. The final sample grain distribution of the powder sample following the crushing and flattening processes is a critical aspect of the RLS instrument that has a direct impact on its overall performance, related to its mineral identification and operational capabilities. This paper provides a comparative overview of the performance of a set of Raman instruments, the RLS micro‐Raman Laboratory Equipment, the RLS ExoMars Simulator, and the RLS Engineering and Qualification Model (EQM) using Martian representative crushed samples, along with an evaluation of instrument performance as a function of the operational scenario. The results from the work performed by the RLS team confirm the capability of the RLS instrument performances, by acquiring good‐quality spectra from crushed samples provided by the SPDS, whose science return can be further optimized when improving the RLS instrument operation sequence. [ABSTRACT FROM AUTHOR]

The Raman laser spectrometer (RLS) instrument onboard the Rosalind Franklin rover of the ExoMars 2022 mission will analyze powdered samples on Mars to search for traces of life. To prepare for the mission, the RLS scientific team has developed the RLS ExoMars Simulator (RLS Sim), a flexible model of RLS that operates similarly to the actual instrument, both in laboratory and field conditions, while also emulating the rover operational constraints in terms of sample distribution that are relevant to the Raman analysis. This system can operate autonomously to perform RLS‐representative analysis in one or several samples, making it very useful to perform heavy experimental tasks that would otherwise be impossible using a flight‐representative model of the instrument. In this work, we introduce the current configuration of the RLS Sim that has incorporated new hardware elements such as the RAman Demonstrator 1 (RAD1) spectrometer with the objective of approaching its performance to that of the actual RLS instrument. To evaluate the scientific capability of the RLS Sim, we have compared it with a replica model of RLS, the RLS Flight Spare (FS). Several acquisition aspects have been evaluated based on the analysis of select samples, assessing the performance in terms of spectral range and resolution and also studying several issues related to the evolution of signal‐to‐noise ratio (SNR) with different acquisition parameters, especially the number of accumulations. This performance analysis has shown that the RLS Sim in its updated configuration will be a key model to perform support science for the ExoMars mission and the RLS instrument on the Rosalind Franklin rover. Designed to work intensively, the use of the RLS Sim in combination with the RLS FS will facilitate maximizing the scientific return of the RLS spectrometer during Martian operations. [ABSTRACT FROM AUTHOR]