Recently discovered siderite globules from Upper Cretaceous cavity and fracture fillings in southern Belgium are described and interpreted with emphasis on the still unsolved problem of the carbonates in meteorite ALH84001, which enclose controversal evidence for ancient Martian life. The most interesting aspects of the carbonates described here are 1) their close association with fossil microbiota, 2) their environment, which is 100% sedimentary, subaerial and not hydrothermal and 3) their morphologies, some of which being similar to those in ALH84001. Although the question of the direct biological influence is not critical in this case, the biogenicity for the minerals will be discussed as a strong possibility and is not only inferred from the simple spatial (and temporal) association of the carbonates and the fossil microbiota. Morphological, textural and chemical data will be presented and interpreted as variations in fluid chemistry related to environmental changes. Although they may appear different from those in Martian meteorite and Spitzbergen xenoliths, the Cretaceous globules originated in subsurface environment which left evident traces of life in the form of fossil microbial/fungal mats. They are thus considered as an opportunity to investigate biosignatures in future research using the wide range of available techniques.

During the past six years, we have conducted extensive scanning electron and optical microscopy investigations and x-ray analysis to determine the morphology, life cycle processes, and elemental distributions in living and fossil cyanobacteria, bacteria, archaea, fungi, and algae sampled from terrestrial environments relevant to Astrobiology. Biominerals, pseudomorphs and microfossils have been studied for diverse microbial groups in various states of preservation in many types of rocks (e.g., oil shales, graphites, shungites, bauxites, limestones, pyrites, phosphorites, and hydrothermal vent chimneys). Results of these studies have been applied to the search for biosignatures in carbonaceous chondrites, stony, and nickel iron meteorites. We review important biomarkers found in terrestrial rocks and meteorites and present additional evidence for the existence of indigenous bacterial microfossils in-situ in freshly fractured surfaces of the Murchison, Rainbow and Tagish Lake carbonaceous meteorites. We provide secondary and backscatter electron images and spectral data obtained with Field Emission and Environmental Scanning Electron Microscopes of biominerals and microfossils. We discuss techniques for discriminating indigenous microfossils from recent terrestrial contaminants. Images are provided of framboidal magnetites in oil shales and meteorites and images and 2D x-ray maps are shown of bacterial microfossils embedded in the mineral matrix of the Murchison, Rainbow and Tagish Lake Carbonaceous Meteorites. These microfossils exhibit characteristics that preclude their interpretation as post-arrival contaminants and we interpret them as indigenous biogenic remains.

The performance of the PAW instrumentation on the 60kg Beagle 2 lander for ESA’s 2003 Mars Express mission will be described. Beagle 2 will search for organic material on and below the surface of Mars in addition to a study of the inorganic chemistry and mineralogy of the landing site. The lander will utilize acquisition and preparation tools to obtain samples from below the surface, and both under and inside rocks. In situ analysis will include examination of samples with an optical microscope, Mossbauer and fluorescent X-ray spectrometers. Extracted samples will be returned to the lander for analysis, in particular a search for organics and a measurement of their isotopic composition. The PAW experiment performance data will be described along with the status of the project.

Two key infrared instrument components, high resolution silicon grisms and cryogenic image slicers, are being developed at Penn State under NASA support for potential applications in future Mars missions. These new instrument components are planned to be used in a new kind of instrument called a CUBE Machine for detecting and characterizing possible organic compounds on the martian surface through spectroscopically observing martian rocks, soil, and organic matter in IR wavelengths (1-5 μm). It is a compact, robust and light-weight 3D near-IR imaging spectrometer and takes full advantage of these new instrument components to enable an order of magnitude improvement in spectral resolution and observing efficiency and also large simultaneous wavelength coverage (~1-5 μm). Due to high dispersion (n = 3.4), silicon grisms provide at least 2 times higher spectral dispersion than any commercially made grisms. These silicon grisms will be the key elements for making the instrument compact enough to fit into spacecrafts and simultaneously provide high enough spectral resolution to resolve the weak spectral features from organic materials. The reflective imaging slicers enable us to collect spectral information from the Mars surface in three dimensional form - two spatial dimensions and one spectral dimension. This unique capability obviates the need to make many scans to build up the data cube as traditional instruments such as spot scanned spectrometers, or slit scanned spectrometers, resulting in an order of magnitude increase in observing efficiency. In addition, use of the Cube Machine to produce spectral maps of a target body will result in dramatically reduced operational complexity, data processing complexity, and increased geometric fidelity of the final data. With current available large IR arrays such as 2kx2k HgCdTe arrays this new instrument will provide large simultaneous wavelength coverage at high spectral resolution. We have successfully developed silicon grisms with 1 inch in dimension and 54.7 degree in blaze angle. These grisms can provide a diffraction-limited spectral resolution of R~20,000 at 2 μm, which is already high enough for most astrobiology space mission applications. The grisms have very smooth grating facets, with typical rms roughness of ~9 nm, indicating a total integrated scattered light level less than 1% in the entire IR wavelengths to allow high precision spectroscopy. The optical design of the image slicers has been finished. The optics required to assemble a prototype image slicer is being procured.

Fossiliferous sandstones of the Upper Ordovician (Lorraine Group) found along the Erie-Ontario Lowlands represent near-shore marine invertebrate communities which dominated the warm shallow sea that existed in this region 450 my ago. Subsequent glacial scouring and breakup of this ancient seabed during the Pleistocene resulted in its being buried under glacial sediments and soil. Then over a period of thousands of years, mild carbonic acid from rainwater mixed with humic acids from soil percolated through the sandstones and dissolved the entombed fossils leaving only dissolution cavities. This same process is how caves and karst features are formed. Rocks imaged by NASA’s Viking 2 lander in 1976 revealed ubiquitous “vesicles” that to this day remain enigmatic because the mineralogy of Martian rocks has not been adequately analyzed to date. Neither a sedimentary nor a volcanic origin for the rocks has been firmly established. Furthermore, proposed theories on the evolution of the Utopia Basin near the Viking 2 landing site include an ancient shallow ocean and glacial scouring. If Mars did indeed have an ocean at one point in its history, then the question must be asked “Did Martian lakes and oceans also have time enough for the development of life and ultimately to the multicellular stage that may have left traces of their existence as dissolution cavities? In this report, attention is drawn to the morphological similarities of biogenic dissolution cavities in terrestrial sandstones and in the near-field rocks at the Viking 2 landing site on Mars. The Beagle 2 astrobiology lander, part of the ESA’s Mars Express mission in 2003, will once again land in the northern plains of Mars not far from the shoreline of the proposed northern ocean basin. A comparison of the rocks from the Beagle 2 landing site to those at Viking 2 may shed further light on whether they are sedimentary or volcanic in origin, and, of greatest interest, whether the vesicles in the Martian rocks constitute analogs to the biologically formed dissolution cavities in the rocks of the Upper Ordovician on Lake Ontario.

The Microarray Assay for Solar System Exploration (MASSE) will use a microarray of antibody tests to search for biomarkers in extraterrestrial environments. In order for this technology to be useful for in situ studies on any given planet, molecules present within the material examined must be extracted and recognizable to the antibodies used in the assays. Experiments are currently being conducted on the immunological detection of agents in environmental samples, including soils and JSC Mars - 1 Martian regolith simulant and progress and results of immunological testing of material containing biomarkers for viable life will be presented and discussed in the context of the development of the MASSE instrument.

Since the 1976 Viking Mission to Mars, follow-on efforts to resolve its controversial life detection results have been thwarted by two heretofore insurmountable difficulties: the huge expense of sterilizing the entire spacecraft to protect the integrity of life detection experiments; and the lack of a practical robotic life detection package that could produce results acceptable as unambiguous by the scientific community. We here present a method that assures sterility and the complete integrity of robotic life detection experiments, all at a negligible cost. Second, we propose a candidate set of integrated, highly sensitive experiments that we believe could produce results acceptable to the vast majority of scientists. In addition to the biology-chemistry issue, the extensively debated oxidative state of the Martian surface and other chemical and physical characteristics of the Martian soil would be determined. We present our concept for a miniaturized instrument that could carry out a number of candidate experiments to achieve the objective.

The mineralogy of the surface material of Mars is the key to disclose its present and past life and climates. Clay mineral species, carbonates, and ice (water and CO2) are and/or contain their witnesses. X-ray powder diffraction (XRPD) is the most powerful analytical method to identify and quantitatively characterize minerals in complex mixtures. This paper discusses the development of a working model of an instrument consisting of a reflection mode diffractometer and a transmission mode CCD-XRPD instrument, combined with an XRF module. The CCD-XRD/XRF instrument is analogous to the instrument for Mars missions developed by Sarrazin et al. (1998). This part of the tandem instrument enables "quick and dirty" analysis of powdered (!) matter to monitor semi-quantitatively the presence of clay minerals as a group, carbonates, and ices and yields semi-quantitative chemical information from X-ray fluorescence (XRF). The reflection mode instrument (i) enables in-situ measurements of rocks and soils and quantitative information on the compounds identified, (ii) has a high resolution and reveals large spacings for accurate identification, in particular of clay mineral species, and (iii) the shape of the line profiles observed reveals the kind and approximate amounts of lattice imperfections present. It will be shown that the information obtained with the reflection mode diffractometer is crucial for finding signs of life and changes in the climate on Mars. Obviously this instrument can also be used for other extra-terrestrial research.

Soils and landscapes form the carpet of the earth’s surface which is in permanent geodynamic evolution and almost uninterruptedly be followed over the last 65 million Earth years since the Tertiary. The present geo-morphological traverse is composed of landscapes which over the last 2.4 million years of the Quaternary Epoch developed in harmony with the prevailing climatic belt along the parallels of latitude. Landscapes occur at the boundary of lithosphere and atmosphere and depend from the perennial changing geochemistry of the atmosphere. The sea and the oceans as well as the lakes are part of these landscapes and change also accordingly. Soils form today and formed in the geological past on top of these landscapes and represent an important habitat of life. Red Soils on Earth are bound today to the tropical belt. With changing geochemistry of the atmosphere the red soils covered some 7-10 Million years ago also the surface of the Earth till 73°N and S Latitude in a continuously ambient tropoid environment shaping planation surfaces. Earth from this point of view, was a Red Planet of which relicts are found from Lapland till Antarctica. The red cover occurring on the surface of Mars between the poles may then be a similar stage of the past.

Calculating palaeoclimatic cycles on a wide range of geological parameters of the Earth revealed the absolute dependence of climatic change on planetary and Sun orbital characteristics and resonances. Mars Orbiter Camera (MOC) images MOC2_148 and MOC2_300, taken from huge canyons near the north polar region clearly show a periglacial permafrost sequence of sedimentary layers which are of different repetitive thicknesses. The fact that such layers have been rhythmically deposited inheres the existence of a fossil or palaeo-dynamic sedimentary environment. Since thickness of the sediment layers differs, the relative sedimentation rate (Relative-Sediment-Deposit-Genetic-Rate (RSDGR)) is taken for a standard parameter. Application of two especially for this purpose tested successive AR algorithms (ExSpect-Matlab) reveals the existence of short RSDGR cycles on Mars ranging from 1,000 years through 10,000 and 40,000 years. The short-term cycles (less than 10,000 years) coincide with the small palaeoclimatic changes on Earth, defined by planetary resonances and Sun activity; instead the larger ones correspond with the larger desertification cycles (glacial-interglacial) on Earth, depending on planetary orbital behavior (the so-called Milankovitch cycles). Time span simulations were executed on the Mars sediment series, corresponding to well known Stages of the Quaternary System on Earth (2.4 Million years and less) and on the large Geological Era’s of the Earth (4.6 Billion years and less). It was found that only small cyclicities (400,000 and less) could be calculated on basis of the RSDGR derived from MOC2_148 and MOC2_300 images. No correspondence with known cyclicities on Earth occur when deposition time span is simulated as being longer than 2.4 million years. This fact leads to the assumption that RSDGR events on Mars cover a much shorter time span. Since the sediment series lay on the surface of Mars, the genetic geological dynamics will first be described in detail. Furthermore, it will be investigated by the same method how recent the surface depositional event may be. Calculation results in an approximative age of 125,000 years, called on Earth the “Last Glacial-Last Interglacial Cycle”. Correspondence with Holocene (last 12500 years) cycles on Earth prove that the RSDGR process is active today.

Using organisms from extreme terrestrial environments as models for extraterrestrial life may lead us to underestimate the range of environments that life may inhabit. An alternative approach is to inspect the range of conditions over which crucial biomolecules might function. Recent investigations of enzyme activity suggest that they have the potential to function over a wider range of environmental conditions than expected. Although the upper temperature limit for enzyme stability is unclear, some enzymes are active up to 130°C. The evidence is that the instability of enzymes is a functional requirement, rather then because of any restraint on achieving higher stability. There is no evidence that enzyme activity ceases at low temperatures; it declines in a predictable manner to the lowest temperature at which it has been possible to make measurements, -100°C. It has been generally accepted that dehydration stops enzyme activity but this acceptance may have arisen partly from the technical difficulty of assessing enzyme activity without a fluid medium for diffusion. Experiments using anhydrous organic solvents or gas phase substrates suggest activity occurs in enzymes at very low hydration.

The bacterial diversity of microbial extremophiles from the meromictic, hypersaline Mono Lake and a small evaporite pool in Owens Lake of California was studied. In spite of these regions had differing mineral background and different concentrations of NaCl in water they contain the same halo- alkaliphiles anaerobic bacterial community. Three new species of bacteria were detected in this community: primary anaerobe, dissipotrophic saccharolytic spirochete Spirochaeta americana strain AspG1^T, primary anaerobe which is proteolytic Tindallia californiensis strain APO^T, and secondary anaerobe, hydrogen using Desulfonatronum thiodismutans strain MLF1^T, which is sulfate- reducer with chemo-litho-autotrophic metabolism. All of these bacteria are obligate alkaliphiles and dependent upon Na⁺ ions and CO₃^2- ions in growth mediums. It is interesting that closest relationships for two of these species were isolates from samples of equatorial African soda Magadi lake: Spirochaeta americana AspG1^T has 99.4% similarity on 16S rDNA- analyses with Spirochaeta alkalica Z- 7491^T, and Tindallia californiensis APO^T has 99.1% similarity with Tindallia magadiensis Z-7934^T. But result of DNA-DNA- hybridization demonstrated less then 50% similarity between Spirochaeta americana AspG1^T and Spirochaeta alkalica Z-7491^T. Percent of homology between Tindallia californiensis APO^T and Tindallia magadiensis Z-7934^T is only 55%. The sulfate-reducer from the alkalic anaerobic community of Magadi lake Desulfonatronovibrio hydrogenovorans Z-7935^T was phylogenetically distant from this sulfate-reducer in Mono lake, but genetically closer (99.7% similarity) to the sulfate-reducer, isolated from Central Asian alkalic lake Khadyn in Siberia Desulfonatronum lacustre Z-7951^T. The study of key enzymes (hydrogenase and CO- hydrogenase) in Tindallia californiensis APO^T and Desulfonatronum thiodismutans MLF1^T showed the presence of high activity of both the enzymes in first and only hydrogenase in second isolate. These results indicate that the athalassic, soda Mono and Owens lakes contain an anaerobic alkaliphilic bacterial community with common ancestors of geographically distant regions, but very same in morphological and functional aspects. As suggested Zavarzin, halo- alkaliphiles may represent relics of microbial life from the early formation of the ancient Earth before the Neoproterozoic period.

The protein synthesis machinery is believed to have largely evolved before the last common ancestor of life on Earth as we know it. Thus, an understanding of ribosomal history will provide insight to the transition period between the last common ancestor and the RNA World. It is argued here that much of this history has been preserved in the primary sequences and three-dimensional structures of the various ribosomal components. In order to understand this history, it is necessary to identify timing insights that can provide clues to the relative age of various aspects of the ribosomal machinery. Such information can be obtained in a variety of ways. Several examples of how such information might be obtained are discussed. Finally, a tentative outline of the order of major events in ribosome history is presented.

The conceptual boundaries of life are rapidly expanding far beyond the confines of our planet to encompass an ever-widening region of the universe. Complex organic molecules in interstellar dust and comets appear most plausibly to be biologically derived, or at least closely related spectroscopically and structurally to such material. A de novo origin of life from non-living material is reckoned to have so minuscule a probability that its occurrence once in the universe can be considered miracle enough. The widespread distribution of similar material (e.g with the characteristics of the diffuse infrared bands and 2175 absorption features) throughout the galaxy and in external galaxies adds weight to the theory of panspermia, where it is supposed that the components of life at a generic level are readily transferred from one place to another. Spectroscopic evidence consistent with life extends to redshifts z=0.83, and from elemental abundance studies alone (e.g, of C, O and metals) in distant galaxies the possibility of cosmic life extends to redshifts as high as z=2.7.

Samples of air removed from the stratosphere, at an altitude of 41km, were previously found to contain viable, but non-cultureable bacteria (cocci and rods). Here, we describe experiments aimed at growing these organisms, together with any others, present in the samples. Two bacteria (Bacillus simplex and Staphylococcus pasteuri) and a single fungus, Engyodontium albus (limber)de Hoog were isolated from the samples. Contamination can never be ruled out when space-derived samples are studied on earth, however, we are confident that the organisms isolated here originated from the stratosphere.