Frances Westall

Frances Westall
CNRS-Orléans · Centre de Biophysique Moléculaire

PhD

About

498
Publications
123,216
Reads
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10,614
Citations
Additional affiliations
January 2002 - present
CNRS Orleans Campus
Position
  • Managing Director
Description
  • I head the Exobiology group: prebiotic chemistry, microbial biosignatures, early life, geological environment of the early Earth, life on Mars (MSL, ExoMars 2018, Mars 2020), International Mars Analogue Rockstore (ISAR: www.isar.cnrs-orleans.fr)
Education
August 1977 - April 1984
University of Cape Town
Field of study
  • Marine geology

Publications

Publications (498)
Article
Two rover missions to Mars aim to detect biomolecules as a sign of extinct or extant life with, among other instruments , Raman spectrometers. However, there are many unknowns about the stability of Raman-detectable bio-molecules in the martian environment, clouding the interpretation of the results. To quantify Raman-detectable biomolecule stabili...
Article
Full-text available
While complexity is observed everywhere in living organisms, it remains an outstanding challenge to establish controlled synthetic approaches allowing one to obtain a high level of programmed organization. Metal–organic frameworks (MOFs) belong to a fascinating family of materials with which it is possible to obtain different levels of structural c...
Article
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The middle Eocene ironstone of the Transylvanian Basin, Romania, provides new insight into the genesis and paleoenvironmental significance of ferruginous ooids. An horizon at the base of the Cȃpus ß Formation in northwestern Romania, well known for the spectacular nummulite banks there exposed, documents a peculiar association of large foraminifera...
Article
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An essential part of the Exomars 2022 payload is the Mars Multispectral Imager for Subsurface Studies (Ma_MISS) experiment hosted by the drill system. Ma_MISS is a visible and near-infrared (0.4–2.3 μ m) miniaturized spectrometer with an optical head inside the drill tip capable of observing the drill borehole with a spatial resolution of 120 μ m....
Article
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The identification of reliable biomarkers, such as amino acids, is key for the search of extraterrestrial life. A large number of microorganisms metabolize, synthesize, take up and excrete amino acids as part of the amino acid metabolism during aerobic and/or anaerobic respiration or in fermentation. In this work, we investigated whether the anaero...
Article
Organic molecules are prime targets in the search for life on other planetary bodies in the Solar System. Understanding their preservation potential and detectability after ionic irradiation, with fluences potentially representing those received for several millions to billions of years at Mars or in interplanetary space, is a crucial goal for astr...
Article
Organic molecules are prime targets in the search for life on other planetary bodies in the Solar System. Understanding their preservation potential and detectability after ionic irradiation, with fluences potentially representing those received for several millions to billions of years at Mars or in interplanetary space, is a crucial goal for astr...
Chapter
EURO—CARES (European Curation of Astromaterials Returned from the Exploration of Space) was a European Commission funded project under the Horizon 2020 Research and Innovation program and ran between January 2015 and December 2017. The core project team was made up of academic and industry experts from 14 different organisations from the United Kin...
Article
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Samples returned from Mars would be placed under quarantine at a Sample Receiving Facility (SRF) until they are considered safe to release to other laboratories for further study. The process of determining whether samples are safe for release, which may involve detailed analysis and/or sterilization, is expected to take several months. However, th...
Article
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The Mars Sample Return Planning Group 2 (MSPG2) was tasked with identifying the steps that encompass all the curation activities that would happen within the MSR Sample Receiving Facility (SRF) and any anticipated curation-related requirements. An area of specific interest is the necessary analytical instrumentation. The SRF would be a Biosafety Le...
Article
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The most important single element of the "ground system" portion of a Mars Sample Return (MSR) Campaign is a facility referred to as the Sample Receiving Facility (SRF), which would need to be designed and equipped to receive the returned spacecraft, extract and open the sealed sample container, extract the samples from the sample tubes, and implem...
Article
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The Mars Sample Return (MSR) Campaign must meet a series of scientific and technical achievements to be successful. While the respective engineering responsibilities to retrieve the samples have been formalized through a Memorandum of Understanding between ESA and NASA, the roles and responsibilities of the scientific elements have yet to be fully...
Article
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Dust transported in the martian atmosphere is of intrinsic scientific interest and has relevance for the planning of human missions in the future. The MSR Campaign, as currently designed, presents an important opportunity to return serendipitous, airfall dust. The tubes containing samples collected by the Perseverance rover would be placed in cache...
Article
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The Mars Sample Return (MSR) Campaign represents one of the most ambitious scientific endeavors ever undertaken. Analyses of the martian samples would offer unique science benefits that cannot be attained through orbital or landed missions that rely only on remote sensing and in situ measurements, respectively. As currently designed, the MSR Campai...
Article
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The NASA/ESA Mars Sample Return (MSR) Campaign seeks to establish whether life on Mars existed where and when environmental conditions allowed. Laboratory measurements on the returned samples are useful if what is measured is evidence of phenomena on Mars rather than of the effects of sterilization conditions. This report establishes that there are...
Article
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Powdered rocks are commonly present at the surface of extraterrestrial bodies and are widely analysed by in situ space probes. Moreover, a number of rovers exploring the surface of Mars are equipped with drills enabling them to access unaltered material and collect samples. During drilling operations, a cone of powder made of the drilled materials...
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In this work, we address the difficulty of reliably identifying traces of life on Mars. Several independent lines of evidence are required to build a compelling body of proof. In particular, we underline the importance of correctly interpreting the geological and mineralogical context of the sites to be explored for the presence of biosignatures. W...
Article
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Optical microscopy analyses using thin sections is one of the most standard techniques in geology. It permits identification of most rock-forming minerals and it is essential for micropaleontology since observation in transmitted light is the only way to observe individual, or colonies of, microfossils in their mineralogical and textural context. T...
Chapter
Sample return missions are among the most exciting space missions, providing both scientifically unique information and an unparalleled mechanism for the inspiring the public. Returned samples allow us to make critical ground truth measurements that can calibrate remote sensing measurements from spacecraft. Some scientific studies can only be done...
Article
Full-text available
The exclusive presence of β -D-ribofuranose in nucleic acids is still a conundrum in prebiotic chemistry, given that pyranose species are substantially more stable at equilibrium. However, a precise characterisation of the relative furanose/pyranose fraction at temperatures higher than about 50 °C is still lacking. Here, we employ a combination of...
Article
Full-text available
The Kaapvaal and Zimbabwe cratons host some of the earliest evidence for life. When compared to the contemporaneous East Pilbara craton, cherts and other metasedimentary horizons in southern Africa preserve traces of life with far greater morphological and geochemical fidelity. In spite of this, most fossiliferous horizons of southern Africa have r...
Article
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Astrobiology is often regarded as the study of life beyond Earth, but here we consider life on Earth through an astrobiological lens. Microbiology has historically focused on various anthropocentric sub‐fields (such as fermented foods or commensals and pathogens of crop plants, livestock, and humans), but addressing key biological questions via ast...
Article
Europa is the closest and probably the most promising target to search for extant life in the Solar System, based on complementary evidence that it may fulfil the key criteria for habitability: the Galileo discovery of a sub-surface ocean; the many indications that the ice shell is active and may be partly permeable to transfer of chemical species,...
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Background Extreme terrestrial, analogue environments are widely used models to study the limits of life and to infer habitability of extraterrestrial settings. In contrast to Earth’s ecosystems, potential extraterrestrial biotopes are usually characterized by a lack of oxygen. Methods In the MASE project (Mars Analogues for Space Exploration), we...
Article
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The practical limitations inherent to human and robotic planetary exploration necessitate the development of specific protocols and methods. This non-standard approach requires testing and validation phases in order to optimize instrumental setups and improve data interpretation; this can occur prior to, during, or even after a mission. Flight inst...
Article
Executive Summary In this White Paper we propose that NASA works with ESA and other potentially interested international partners to design and fly jointly an ambitious and exciting planetary mission to characterize Europa’s habitability and search for bio-signatures in the environment of Europa (surface, subsurface and exosphere). By choosing the...
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Alteration of organic remains during the transition from the bio- to lithosphere is afected strongly by biotic processes of microbes infuencing the potential of dead matter to become fossilized or vanish ultimately. If fossilized, bones, cartilage, and tooth dentine often display traces of bioerosion caused by destructive microbes. The causal agent...
Article
Full-text available
Alteration of organic remains during the transition from the bio-to lithosphere is affected strongly by biotic processes of microbes influencing the potential of dead matter to become fossilized or vanish ultimately. If fossilized, bones, cartilage, and tooth dentine often display traces of bioerosion caused by destructive microbes. The causal agen...
Preprint
The exclusive presence of $\beta$-D-ribofuranose in nucleic acids is still a conundrum in prebiotic chemistry, given that pyranose species are substantially more stable at equilibrium. However, a precise characterisation of the relative furanose/pyranose fraction at temperatures higher than about 50$^{\,\rm o}$C is still lacking. Here, we employ a...
Article
Full-text available
Limited taxonomic classification is possible for Archaean microbial mats and this is a fundamental limitation in constraining early ecosystems. Applying Fourier transform infrared spectroscopy (FTIR), a powerful tool for identifying vibrational motions attributable to specific functional groups, we characterized fossilized biopolymers in 3.5-3.3 Ga...
Article
Europa is the closest and probably the most promising target to search for extant life in the Solar System, based on complementary evidence that it may fulfil the key criteria for habitability: the Galileo discovery of a sub-surface ocean; the many indications that the ice shell is active and may be partly permeable to transfer of chemical species,...
Article
Full-text available
Precambrian cellular remains frequently have simple morphologies, micrometric dimensions and are poorly preserved, imposing severe analytical and interpretational challenges, especially for irrefutable attestations of biogenicity. The 1.88 Ga Gunflint biota is a Precambrian microfossil assemblage with different types and qualities of preservation a...
Chapter
Full-text available
Five bacterial (facultatively) anaerobic strains, namely Buttiauxella sp. MASE-IM-9, Clostridium sp. MASE-IM-4, Halanaerobium sp. MASE-BB-1, Trichococcus sp. MASE-IM-5, and Yersinia intermedia MASE-LG-1 isolated from different extreme natural environments were subjected to Mars relevant environmental stress factors in the laboratory under controlle...
Article
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Modern biological dependency on trace elements is proposed to be a consequence of their enrichment in the habitats of early life together with Earth's evolving physicochemical conditions; the resulting metallic biological complement is termed the metallome. Herein, we detail a protocol for describing metallomes in deep time, with applications to th...
Article
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Palaeoarchaean cherts preserve the most ancient direct traces of life, but this palaeobiological testament is rarely assimilated into ecosystem or biome models. Trace and rare earth element plus yttrium (REE+Y) compositions reliably decode the palaeodepositional settings of these cherts, and thus constrain the environments within which early microb...
Article
Five bacterial (facultatively) anaerobic strains, namely Buttiauxella sp. MASE-IM-9, Clostridium sp. MASE-IM-4, Halanaerobium sp. MASE-BB-1, Trichococcus sp. MASE-IM-5, and Yersinia intermedia MASE-LG-1 isolated from different extreme natural environments were subjected to Mars relevant environmental stress factors in the laboratory under controlle...
Article
Full-text available
The aim of this article is to provide the reader with an overview of the different possible scenarios for the emergence of life, to critically assess them and, according to the conclusions we reach, to analyze whether similar processes could have been conducive to independent origins of life on the several icy moons of the Solar System. Instead of...
Article
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We propose an innovative method based on photography and image processing of interdisciplinary relevance, permitting the uncomplicated and inexpensive evaluation of material properties. This method—CaliPhoto—consists of using a dedicated colour plate with a specific design, placed in the field of view of a photograph of the material to be character...
Article
Full-text available
One of the main objectives for astrobiology is to unravel and explore the habitability of environments beyond Earth, paying special attention to Mars. If the combined environmental stress factors on Mars are compatible with life or if they were less harsh in the past, to investigate the traces of past or present life is critical to understand its p...
Article
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The ExoMars 2020 mission will characterise a Martian locality with potential former habitability – Oxia Planum – and attempt to identify preserved morphological and chemical biosignatures. The payload will include a drill retrieving cores from the subsurface (up to 2m depth), which will be imaged at high resolution by two instruments: the Panoramic...
Article
Full-text available
Morphologically diverse organo-sedimentary structures (including microbial mats and stromatolites) provide a palaeobiological record through more than three billion years of Earth history. Since understanding much of the Archaean fossil record is contingent upon proving the biogenicity of such structures, mechanistic interpretations of well-preserv...
Article
Jurassic siliceous hot-spring (sinter) deposits from Argentine Patagonia were evaluated to determine the distribution and preservation quality of their entombed microbial fabrics. Detailed study showed that the Claudia palaeo-geothermal field hosts the best-preserved sinter apron in the Deseado Massif geological province, where we also found hot-sp...
Conference Paper
Full-text available
EURO-CARES (European Curation of Astromaterials Returned from the Exploration of Space) was a three-year multinational project (2015–2017) funded by the European Commission's Horizon 2020 research programme. The objective of EURO-CARES was to create a roadmap for the implementation of a European Extra-terrestrial Sample Curation Facility (ESCF). Th...
Article
Electron paramagnetic resonance (EPR) analysis of carbonaceous, volcanic, tidal sediments from the 3.33 Ga-old Josefsdal Chert (Kromberg Formation, Barberton Greenstone Belt), documents the presence of two types of insoluble organic matter (IOM): (1) IOM similar to that previously found in Archean cherts from numerous other sedimentary rocks in the...
Article
Full-text available
Return of samples from the surface of Mars has been a goal of the international Mars science community for many years. Strategies for the collection of such samples have ranged from “grab and go” acquisition from the surface, to dust collection in the atmosphere, to scientific selection by geologically capable rovers. As comprehension of the comple...
Article
Full-text available
Return of samples from the surface of Mars has been a goal of the international Mars science community for many years. Affirmation by NASA and ESA of the importance of Mars exploration led the agencies to establish the international MSR Objectives and Samples Team (iMOST). The purpose of the team is to re‐evaluate and update the sample‐related scie...
Article
Full-text available
This report requested by the International Mars Exploration Working Group (IMEWG). Return of samples from the surface of Mars has been a goal of the international Mars science community for many years. Affirmation by NASA and ESA of the importance of Mars exploration led the agencies to establish the international MSR Objectives and Samples Team (i...
Conference Paper
EURO-CARES (European Curation of Astromaterials Returned from the Exploration of Space) was a three-year multinational project (2015-2017) funded by the European Commission's Horizon 2020 research programme. The objective of EURO-CARES was to create a roadmap for the implementation of a European Extra-terrestrial Sample Curation Facility (ESCF). Th...