Dr. Jamie H. Wallis Profile

Dr. Jamie H. Wallis

SPIE Involvement:

Author

Proceedings Article | 25 September 2015 Paper

Evidence of ancient microbial activity on Mars

Jamie Wallis, N. Wickramasinghe, Daryl Wallis, Nori Miyake, M. Wallis, Richard Hoover

Proceedings Volume 9606, 96060V (2015) https://doi.org/10.1117/12.2186518

KEYWORDS: Pyrite, Arsenic, Iron, Minerals, Veins, Bacteria, Etching, Carbon, Scanning electron microscopy, Oxidation

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Proceedings Article | 22 September 2015 Paper

Chemical and structural composition of organic carbonaceous structures in Tissint: evidence for a biogenetic origin

Jamie Wallis, N. Wickramasinghe, Daryl Wallis, Nori Miyake, M. Wallis, Richard Hoover

Proceedings Volume 9606, 96060L (2015) https://doi.org/10.1117/12.2186515

KEYWORDS: Raman spectroscopy, Carbon, Crystals, Organic materials, Spectroscopy, Pyrite, Chlorine, Gallium, Coating, Scanning electron microscopy

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Proceedings Article | 22 September 2015 Paper

Carbonaceous structures in the Tissint Martian Meteorite: evidence of a biogenetic origin

Jamie Wallis, N. Wickramasinghe, Daryl Wallis, Nori Miyake, M. Wallis, Richard Hoover

Proceedings Volume 9606, 96060K (2015) https://doi.org/10.1117/12.2186507

KEYWORDS: Pyrite, Scanning electron microscopy, Crystals, Carbon, Photomicroscopy, Contamination, X-rays, Calcite, Backscatter, Minerals

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Proceedings Article | 11 September 2015 Paper

Microbiological investigation of two chondrite meteorites: Murchison and Polonnaruwa

Elena Pikuta, Zhe Lyu, William Whitman, Geneviev LaBrake, Jamie Wallis, Keerthi Wickramarathne, N. Chandra Wickramasinghe, Richard Hoover

Proceedings Volume 9606, 96060M (2015) https://doi.org/10.1117/12.2191203

KEYWORDS: Ultraviolet radiation, Minerals, Contamination, Nitrogen, Microscopy, Soil contamination, Microorganisms, Bacteria, Pluto, Hydrogen

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Proceedings Article | 26 September 2013 Paper

Physical, chemical, and mineral properties of the Polonnaruwa stones

Jamie Wallis, N. Wickramasinghe, Daryl Wallis, Nori Miyake, M. Wallis, Richard Hoover, Anil Samaranayake, Keerthi Wickramarathne, Anthony Oldroyd

Proceedings Volume 8865, 886508 (2013) https://doi.org/10.1117/12.2029607

KEYWORDS: Glasses, Silica, Crystals, Quartz, Oxygen, Statistical analysis, Minerals, Scanning electron microscopy, Absorption, Titanium dioxide

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We report on the physical, chemical and mineral properties of a series of stone fragments recovered from the North Central Province of Sri Lanka following a witnessed fireball event on 29 December 2012. The stones exhibit highly porous poikilitic textures comprising of isotropic silica-rich/plagioclase-like hosts. Inclusions range in size and shape from mm-sized to smaller subangular grains frequently more fractured than the surrounding host and include ilmenite, olivine (fayalitic), quartz and accessory zircon. Bulk mineral compositions include accessory cristobalite, hercynite, anorthite, wuestite, albite, anorthoclase and the high pressure olivine polymorph wadsleyite, suggesting previous endurance of a shock pressure of ~20 GPa. Further evidence of shock is confirmed by the conversion of all plagioclase to maskelynite. Here the infrared absorption spectra in the region 580 cm^-1 to 380 cm^-1 due to the Si-O-Si or Si-O-Al absorption band shows a partial shift in the peak at 380 cm^-1 towards 480 cm^-1 indicating an intermediate position between crystalline and amorphous phase. Host matrix chemical compositions vary between samples, but all are rich in SiO₂. Silica-rich melts display a heterogeneous K-enrichment comparable to that reported in a range of non-terrestrial material from rare iron meteorites to LL chondritic breccias and Lunar granites. Bulk chemical compositions of plagioclase-like samples are comparable to reported data e.g. Miller Ranger 05035 (Lunar), while Si-rich samples accord well with mafic and felsic glasses reported in NWA 1664 (Howardite) as well as data for fusion crust present in a variety of meteoritic samples. Triple oxygen isotope results show Δ¹⁷O = -0.335 with δ¹⁸O (‰ rel. SMOW) values of 17.816 ± 0.100 and compare well with those of known CI chondrites and are within the range of CI-like (Meta-C) chondrites. Rare earth elemental abundances show a profound Europium anomaly of between 0.7 and 0.9 ppm while CI normalized REE patterns accord well with those of high potassium and high aluminium glasses found in lunar and 4 Vesta samples. Twoelement discrimination maps of FeO vs SiO₂, FeO vs TiO₂, FeO vs Al₂O₃ and FeO vs Na₂O similarly match those of impact glasses present in lunar samples and remain within relatively close proximity of the KREEP component. Iridium levels of between 1-7ppm, approximately 104 times that of terrestrial crustal rocks, were detected in all samples.

Proceedings Article | 26 September 2013 Paper

Fossilized diatoms in meteorites from recent falls in Sri Lanka

Richard Hoover, Jamie Wallis, Keerthi Wickramarathne, Anil Samaranayake, George Williams, Gregory Jerman, D. Wallis, N. Wickramasinghe

Proceedings Volume 8865, 886506 (2013) https://doi.org/10.1117/12.2028605

KEYWORDS: Oceanography, Comets, Water, Ocean optics, Scanning electron microscopy, Silica, Spine, Minerals, Magnetic resonance imaging, Microorganisms

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Proceedings Article | 13 November 2012 Paper

Comets as parent bodies of CI1 carbonaceous meteorites and possible habitats of ice-microbes

N. Chandra Wickramasinghe, Janaki Wickramasinghe, Jamie Wallis, Richard Hoover, Alexei Rozanov

Proceedings Volume 8521, 85210Q (2012) https://doi.org/10.1117/12.975979

KEYWORDS: Comets, Liquids, Minerals, Microorganisms, Molecules, Asteroids, Bacteria, Solar system, Fusion energy, Crystals

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Proceedings Article | 24 October 2012 Paper

Possible biological structures in the Tissint Mars Meteorite

Jamie Wallis, N. Chandra Wickramasinghe, Daryl Wallis, Nori Miyake, Max Wallis, Barry Di Gregorio, Richard Hoover

Proceedings Volume 8521, 85210R (2012) https://doi.org/10.1117/12.2013827

KEYWORDS: Mars, Iron, Scanning electron microscopy, Pyrite, Minerals, Particles, X-rays, Sensors, Carbon, Silicon

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Proceedings Article | 23 September 2011 Paper

Comets as parent bodies of CI1 carbonaceous meteorites and possible habitats of ice-microbes

N. Chandra Wickramasinghe, Janaki Wickramasinghe, Jamie Wallis, Richard Hoover, Alexei Rozanov

Proceedings Volume 8152, 81520Z (2011) https://doi.org/10.1117/12.898586

KEYWORDS: Comets, Minerals, Astrobiology, Current controlled current source, Molecules, Molecular biology, Asteroids, Liquids, Earth's atmosphere, Mode conditioning cables

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Recent studies of comets and cometary dust have confirmed the presence of biologically relevant organic molecules along with clay minerals and water ice. It is also now well established by deuterium/hydrogen ratios that the CI1 carbonaceous meteorites contain indigenous extraterrestrial water. The evidence of extensive aqueous alteration of the minerals in these meteorites led to the hypothesis that water-bearing asteroids or comets represent the parent bodies of the CI1 (and perhaps CM2) carbonaceous meteorites. These meteorites have also been shown to possess a diverse array of complex organics and chiral and morphological biomarkers. Stable isotope studies by numerous independent investigators have conclusively established that the complex organics found in these meteorites are both indigenous and extraterrestrial in nature. Although the origin of these organics is still unknown, some researchers have suggested that they originated by unknown abiotic mechanisms and may have played a role in the delivery of chiral biomolecules and the origin of life on Early Earth. In this paper we review these results and investigate the thermal history of comets. We show that permanent as well as transient domains of liquid water can be maintained on a comet under a plausible set of assumptions. With each perihelion passage of a comet volatiles are preferentially released, and during millions of such passages the comet could shed crustal debris that may survive transit through the Earth's atmosphere as a carbonaceous meteorite. We review the current state of knowledge of comets and carbonaceous meteorites. We also present the results of recent studies on the long-term viability of terrestrial ice-microbiota encased in ancient glacial ice and permafrost. We suggest that the conditions which have been observed to prevail on many comets do not preclude either survivability (or even the active metabolism and growth) of many types of eukaryotic and prokaryotic microbial extremophiles-including algae, cyanobacteria, bacteria and archaea. It is argued that the chemical and morphological biomarkers detected on comets and carbonaceous meteorites can be explained by ancient microbial activity without the need to invoke unknown abiotic production mechanisms.