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Extreme environment of the Atacama Desert: Geology, Extremophiles, and its connection to Exobiology
Jíra, Stanislav ; Culka, Adam (advisor) ; Vítek, Petr (referee)
Because of the position in the subtropical climate belt, high altitudes, cold Humboldt Current, Andean rain-shadow, and a few other factors, the Atacama Desert is known for its hyper-arid conditions which are persisting here for a few tens of millions of years. That is why this place is called the driest non-polar place in the world. Aridity is present here since Mesozoic. Because of these conditions, Atacama was thought to be completely inhabitable and inappropriate for any life forms. Despite all the limiting factors, microbial life here exists. Microorganisms have created adaptations in the forms of specialized metabolisms, proteins, and most importantly in form of photoprotective pigments. Except for the structural mechanisms, extremophiles can choose a strategy of living evaporitic minerals, which are quite common in Atacama. For understanding these forms of life many scientific methods are used, for example Raman spectroscopy. Methods that are used here are often used also in extraterrestrial conditions, mainly on the planet Mars, which shares with Atacama few similarities (e.g., some evaporitic minerals). The study of adaptations and capabilities of extremophilic microorganisms can help to broaden the knowledge and understanding of how incredibly resilient life is. Keywords: The Atacama...
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Use of portable Raman spectrometers for detection of sulfates: potential application in exobiology
Košek, Filip ; Jehlička, Jan (advisor) ; Němec, Ivan (referee)
The detection of mineral phases under in situ conditions has become a primary but sometimes also challenging task in many fields of geoscience. Raman spectroscopy has been used as a powerful tool for the identification of various minerals and organic compounds. The advantages and the relative simplicity made this method a promising choice in the future planetary exploration missions to Mars. The deposits of aqueous minerals including sulfates have been found on the Martian surface. With the development of miniaturized handheld spectrometers there is a need for evaluation of Raman spectroscopy as a method of identification of sulfate phases in their natural conditions. In the first part of this work a handheld spectrometer equipped with 532 nm excitation laser was tested under laboratory conditions during which the ability to distinguish mineral samples representing sulfates of different chemical composition and different degree of hydration was investigated. In the second part, two handheld Raman spectrometers equipped with 532 and 785 nm excitation lasers were used for the characterization of sulfate phases on sites of their natural occurrence located in the Czech Republic. The quality of the Raman spectra acquired under outdoor conditions by both spectrometers was rather average but sufficient to...
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Application of Raman spectroscopy for the identification of organic inclusions in minerals for the field of exobiology
Osterrothová, Kateřina ; Jehlička, Jan (advisor) ; Němec, Ivan (referee) ; Vandenabeele, Peter (referee)
The multidisciplinary field of astrobiology has grown rapidly in recent years. The major goals of research in the field have been the search for habitable environments both within and outside our solar system, the search for evidence of prebiotic chemistry and life on Mars and other bodies in our solar system, laboratory and field research into the origins and early evolution of life on Earth, and studies of the potential for life to adapt to challenges on Earth and in space. NASA and ESA are heavily focused on a number of upcoming exploratory missions (e.g., the Mars Science Laboratory, with its planned launch in the fall 2011; ExoMars 2018; and the follow-up Mars Sample Return missions beyond 2020). A Raman spectrometer is now being miniaturized for the ExoMars Rover Instrument Suite. This Raman instrument is expected to be used to identify organic compounds and mineral products that could be related to signatures of life, as well as provide a general mineralogical overview, especially those minerals produced by water- related processes. This thesis describes the results of laboratory investigation into the feasibility of Raman spectroscopy to detect different types of biomarkers (pigments, carboxylic acids, and aminoacids) first mixed in the mineral matrices and...
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Current exobiology missions to Mars. Importance for geoscience and search of Life beyond Earth
Ovcharenko, Vladyslav ; Jehlička, Jan (advisor) ; Culka, Adam (referee)
The relevance of the topic of the bachelor's thesis "Current exobiology missions to Mars" is associated with the awareness of the similarity of some conditions and processes on Earth and Mars. Compared to other planets of the Solar system, Mars is somehow relatively close to our planet in major characteristics: the inclination of the equatorial plane, relief, the length of the day, some atmospheric processes, temperature conditions, etc. Having studied the processes taking place there now, we can better deal with the past and predict the future evolution not only of Mars, but also of Earth. The aim of this work is to overview the current exobiological missions of NASA and ESA to Mars and the assessment of the importance of the information received for earth sciences and search of life beyond the Earth. The subject of Exobiology consists in studies of potential origin, evolution, spread of life on other planets of the universe. Exobiology includes search for habitable environments both in the Solar system and beyond, detecting biomarkers, search of evidence of prebiotic chemistry, and research on potential possibilities of life in terms of adapting to extreme conditions in space. Based on the foregoing, we can state that the exploration of Mars opens up grandiose prospects for science and technology...
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Application of Raman spectroscopy for detection of sulfates of self-ignited coal heaps
Košek, Filip ; Jehlička, Jan (advisor) ; Němec, Ivan (referee) ; Vandenabeele, Peter (referee)
This Ph.D. thesis was focused on the application of Raman spectroscopy as the main analytical method for the characterization of neo-formed minerals, notably sulfates, from burning coal waste dumps. This environment associated with subsurface fires gives rise to a variety of uncommon and rare minerals. The specific features of these minerals (metastability, hygroscopy, mixed aggregates) causes that the mineralogical investigation is a challenging task using traditional laboratory-based techniques. Advantages such as the non-destructive nature, the sensitivity to the changes in the hydration degree of sulfates, little or none pretreatment, and the option of measurements directly in the field were the main reasons for applying this spectroscopy method. The scarce availability of spectroscopic data of most gas-vent minerals can be considered as the disadvantage. Therefore, artificial prepared samples of six anhydrous sulfates, which are rarely found in nature, were analyzed by Raman laboratory spectroscopy and a miniature a Raman spectrometer, and specific Raman features as well the differences with hydrated counterparts are shown. Laboratory investigation of two natural hydrated aluminum sulfates, alunogen and khademite, were carried out using Raman spectroscopy and other methods in order to obtain...
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Carotenoids of snow algae as biomarkers for exobiology: Raman spectroscopic perspective
Němečková, Kateřina ; Jehlička, Jan (advisor) ; Němec, Ivan (referee)
The major aim of this thesis is critical evaluation of Raman spectroscopy in the detection of carotenoids of extremophiles, namely snow algae. Extremophilic microorganisms play an important role in exobiology since they set hypothetical boundaries for the presence of life on Earth. Raman spectroscopy will be a part of two mission to Mars. Here, a laboratory Raman microspectrometer was used for the analysis of 11 samples of snow algae from different locations over the years 2002-2017. The acquired spectra were compared with HPLC/UV-VIS analysis. The results showed that the ability of Raman spectroscopy to discriminate between structurally slightly differing carotenoid pigments or several carotenoids in an admixture is limited. Contrary, HPLC/UV-VIS permitted to detect various structurally similar carotenoids (and chlorophylls). However, HPLC/UV-VIS worked with overall pigment extracts during which some structural information can be lost. Raman microspectrometer allowed analysis of cells in different life-cycle stages and thus several various spectra could be studied. Raman microspectrometer was therefore more suitable for carotenoid detection in mixtures of various life-stages than HPLC/UV-VIS. Key words carotenoids, snow algae, exobiology, habitability, biomarker, Raman spectroscopy, HPLC/UV-VIS
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Application of Raman spectroscopy for the identification of organic inclusions in minerals for the field of exobiology
Osterrothová, Kateřina ; Jehlička, Jan (advisor) ; Němec, Ivan (referee) ; Vandenabeele, Peter (referee)
The multidisciplinary field of astrobiology has grown rapidly in recent years. The major goals of research in the field have been the search for habitable environments both within and outside our solar system, the search for evidence of prebiotic chemistry and life on Mars and other bodies in our solar system, laboratory and field research into the origins and early evolution of life on Earth, and studies of the potential for life to adapt to challenges on Earth and in space. NASA and ESA are heavily focused on a number of upcoming exploratory missions (e.g., the Mars Science Laboratory, with its planned launch in the fall 2011; ExoMars 2018; and the follow-up Mars Sample Return missions beyond 2020). A Raman spectrometer is now being miniaturized for the ExoMars Rover Instrument Suite. This Raman instrument is expected to be used to identify organic compounds and mineral products that could be related to signatures of life, as well as provide a general mineralogical overview, especially those minerals produced by water- related processes. This thesis describes the results of laboratory investigation into the feasibility of Raman spectroscopy to detect different types of biomarkers (pigments, carboxylic acids, and aminoacids) first mixed in the mineral matrices and...
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Use of portable Raman spectrometers for detection of sulfates: potential application in exobiology
Košek, Filip ; Jehlička, Jan (advisor) ; Němec, Ivan (referee)
The detection of mineral phases under in situ conditions has become a primary but sometimes also challenging task in many fields of geoscience. Raman spectroscopy has been used as a powerful tool for the identification of various minerals and organic compounds. The advantages and the relative simplicity made this method a promising choice in the future planetary exploration missions to Mars. The deposits of aqueous minerals including sulfates have been found on the Martian surface. With the development of miniaturized handheld spectrometers there is a need for evaluation of Raman spectroscopy as a method of identification of sulfate phases in their natural conditions. In the first part of this work a handheld spectrometer equipped with 532 nm excitation laser was tested under laboratory conditions during which the ability to distinguish mineral samples representing sulfates of different chemical composition and different degree of hydration was investigated. In the second part, two handheld Raman spectrometers equipped with 532 and 785 nm excitation lasers were used for the characterization of sulfate phases on sites of their natural occurrence located in the Czech Republic. The quality of the Raman spectra acquired under outdoor conditions by both spectrometers was rather average but sufficient to...
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Europa and its importance for exobiology - life in ice
Suchánek, Vladimír ; Jehlička, Jan (advisor) ; Culka, Adam (referee)
Generally we can say, that for life similar to the life on the Earth it is necessary to meet three basic prerequisites. On the surface or below the surface of the planet or the moon there must be liquid water, basic biogenic elements and no less important source of energy. If these requirements are at least partially met, the given place in the universe can be described as a potential source of life. This scientific work is dealing with the possible origins of life on one of Jupiter's moons, named Europa. The thesis is divided into four chapters, where the first three chapters deal with Europa as a place suitable for life. The fourth chapter is focused on the future research of the moon. This work is based on the data obtained from satellites Pioneer 10, Pioneer 11, Voyager 1, Voyager 2 and Galileo. Powered by TCPDF (www.tcpdf.org)
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Estimation of Raman spectrometric instruments (785 nm excitation) for detection of dark minerals
Šimon, Jan ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
Summary: Raman spectroscopy is a widely used method in geoscience fields. Using a portable Raman spectrometer is possible to identify different materials, Raman spectrometer will participate in the survey the Martian surface. Its use is widely applied in mineralogy. There was measured a set of dark, green and some bright minerals of different mineralogical system groups that have been assessed the applicability of the chosen detector excitation at 785 nm mainly off-road equipment. The obtained spectra were measured off-road equipment ahura at excitation 785 nm and laboratory equipment InVia Renishaw and there were used lasers at excitaion of 785 nm and 514 nm. It was set of these minerals: Prehnite, Sulphur, Tyrkenit (howlit), Pyroxene (diopside), Libethenite, Toutmaline (verdelite), Dioptas, Klinoklas, Langit, Jadeit, Pseudomalachit (ehlit), Actinolite, Epidote, Augite. Results are composed of field measurement device Ahura, with excitation 785 nm and laboratory apparatus Invite Renishaw excitations with 785 nm and 514 nm. Measured values are arranged in tables, where the measurements are compared with each other, including literature and reference graphically demonstrated in the form of spectra. Subsequently evaluated their measurability. Keywords: Raman spektroscopy, portable Raman spectrometer,...
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