TY - JOUR A1 - Makuch, Martin A1 - Brilliantov, Nikolai V. A1 - Sremcevic, Miodrag A1 - Spahn, Frank A1 - Krivov, Alexander V. T1 - Stochastic circumplanetary dynamics of rotating non-spherical dust particles JF - Planetary and space science N2 - We develop a model of stochastic radiation pressure for rotating non-spherical particles and apply the model to circumplanetary dynamics of dust grains. The stochastic properties of the radiation pressure are related to the ensemble-averaged characteristics of the rotating particles, which are given in terms of the rotational time-correlation function of a grain. We investigate the model analytically and show that an ensemble of particle trajectories demonstrates a diffusion-like behaviour. The analytical results are compared with numerical simulations, performed for the motion of the dusty ejecta from Deimos in orbit around Mars. We find that the theoretical predictions are in a good agreement with the simulation results. The agreement however deteriorates at later time, when the impact of non-linear terms, neglected in the analytic approach, becomes significant. Our results indicate that the stochastic modulation of the radiation pressure can play an important role in the circumplanetary dynamics of dust and may in case of some dusty systems noticeably alter an optical depth. (c) 2006 Elsevier Ltd. All rights reserved. KW - Mars KW - Deimos KW - ejecta KW - stochastics KW - radiation pressure Y1 - 2006 U6 - https://doi.org/10.1016/j.pss.2006.05.006 SN - 0032-0633 VL - 54 IS - 9-10 SP - 855 EP - 870 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - de Vera, Jean-Pierre Paul A1 - Böttger, Ute A1 - de la Torre Nötzel, Rosa A1 - Sanchez, Francisco J. A1 - Grunow, Dana A1 - Schmitz, Nicole A1 - Lange, Caroline A1 - Hübers, Heinz-Wilhelm A1 - Billi, Daniela A1 - Baque, Mickael A1 - Rettberg, Petra A1 - Rabbow, Elke A1 - Reitz, Günther A1 - Berger, Thomas A1 - Möller, Ralf A1 - Bohmeier, Maria A1 - Horneck, Gerda A1 - Westall, Frances A1 - Jänchen, Jochen A1 - Fritz, Jörg A1 - Meyer, Cornelia A1 - Onofri, Silvano A1 - Selbmann, Laura A1 - Zucconi, Laura A1 - Kozyrovska, Natalia A1 - Leya, Thomas A1 - Foing, Bernard A1 - Demets, Rene A1 - Cockell, Charles S. A1 - Bryce, Casey A1 - Wagner, Dirk A1 - Serrano, Paloma A1 - Edwards, Howell G. M. A1 - Joshi, Jasmin Radha A1 - Huwe, Björn A1 - Ehrenfreund, Pascale A1 - Elsaesser, Andreas A1 - Ott, Sieglinde A1 - Meessen, Joachim A1 - Feyh, Nina A1 - Szewzyk, Ulrich A1 - Jaumann, Ralf A1 - Spohn, Tilman T1 - Supporting Mars exploration BIOMEX in Low Earth Orbit and further astrobiological studies on the Moon using Raman and PanCam technology JF - Planetary and space science N2 - The Low Earth Orbit (LEO) experiment Biology and Mars Experiment (BIOMEX) is an interdisciplinary and international space research project selected by ESA. The experiment will be accommodated on the space exposure facility EXPOSE-R2 on the International Space Station (ISS) and is foreseen to be launched in 2013. The prime objective of BIOMEX is to measure to what extent biomolecules, such as pigments and cellular components, are resistant to and able to maintain their stability under space and Mars-like conditions. The results of BIOMEX will be relevant for space proven biosignature definition and for building a biosignature data base (e.g. the proposed creation of an international Raman library). The library will be highly relevant for future space missions such as the search for life on Mars. The secondary scientific objective is to analyze to what extent terrestrial extremophiles are able to survive in space and to determine which interactions between biological samples and selected minerals (including terrestrial, Moon- and Mars analogs) can be observed under space and Mars-like conditions. In this context, the Moon will be an additional platform for performing similar experiments with negligible magnetic shielding and higher solar and galactic irradiation compared to LEO. Using the Moon as an additional astrobiological exposure platform to complement ongoing astrobiological LEO investigations could thus enhance the chances of detecting organic traces of life on Mars. We present a lunar lander mission with two related objectives: a lunar lander equipped with Raman and PanCam instruments which can analyze the lunar surface and survey an astrobiological exposure platform. This dual use of testing mission technology together with geo- and astrobiological analyses will significantly increase the science return, and support the human preparation objectives. It will provide knowledge about the Moon's surface itself and, in addition, monitor the stability of life-markers, such as cells, cell components and pigments, in an extraterrestrial environment with much closer radiation properties to the surface of Mars. The combination of a Raman data base of these data together with data from LEO and space simulation experiments, will lead to further progress on the analysis and interpretation of data that we will obtain from future Moon and Mars exploration missions. KW - Moon KW - Mars KW - Low Earth Orbit KW - Astrobiology KW - Instrumentation KW - Spectroscopy KW - Biosignature Y1 - 2012 U6 - https://doi.org/10.1016/j.pss.2012.06.010 SN - 0032-0633 VL - 74 IS - 1 SP - 103 EP - 110 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Schirmack, Janosch A1 - Boehm, Michael A1 - Brauer, Chris A1 - Löhmannsröben, Hans-Gerd A1 - de Vera, Jean-Pierre Paul A1 - Moehlmann, Diedrich A1 - Wagner, Dirk T1 - Laser spectroscopic real time measurements of methanogenic activity under simulated Martian subsurface analog conditions JF - Planetary and space science N2 - On Earth, chemolithoautothrophic and anaerobic microorganisms such as methanogenic archaea are regarded as model organisms for possible subsurface life on Mars. For this reason, the methanogenic strain Methanosarcina soligelidi (formerly called Methanosarcina spec. SMA-21), isolated from permafrost-affected soil in northeast Siberia, has been tested under Martian thermo-physical conditions. In previous studies under simulated Martian conditions, high survival rates of these microorganisms were observed. In our study we present a method to measure methane production as a first attempt to study metabolic activity of methanogenic archaea during simulated conditions approaching conditions of Mars-like environments. To determine methanogenic activity, a measurement technique which is capable to measure the produced methane concentration with high precision and with high temporal resolution is needed. Although there are several methods to detect methane, only a few fulfill all the needed requirements to work within simulated extraterrestrial environments. We have chosen laser spectroscopy, which is a non-destructive technique that measures the methane concentration without sample taking and also can be run continuously. In our simulation, we detected methane production at temperatures down to -5 degrees C, which would be found on Mars either temporarily in the shallow subsurface or continually in the deep subsurface. The pressure of 50 kPa which we used in our experiments, corresponds to the expected pressure in the Martian near subsurface. Our new device proved to be fully functional and the results indicate that the possible existence of methanogenic archaea in Martian subsurface habitats cannot be ruled out. (C) 2013 Published by Elsevier Ltd. KW - Mars KW - Methanogens KW - Methane KW - Sub-zero temperature (Celsius) KW - Wavelength modulation spectroscopy (laser spectroscopy) Y1 - 2014 U6 - https://doi.org/10.1016/j.pss.2013.08.019 SN - 0032-0633 VL - 98 SP - 198 EP - 204 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Knapmeyer-Endrun, Brigitte A1 - Golombek, Matthew P. A1 - Ohrnberger, Matthias T1 - Rayleigh Wave Ellipticity Modeling and Inversion for Shallow Structure at the Proposed InSight Landing Site in Elysium Planitia, Mars JF - Space science reviews N2 - The SEIS (Seismic Experiment for Interior Structure) instrument onboard the InSight mission will be the first seismometer directly deployed on the surface of Mars. From studies on the Earth and the Moon, it is well known that site amplification in low-velocity sediments on top of more competent rocks has a strong influence on seismic signals, but can also be used to constrain the subsurface structure. Here we simulate ambient vibration wavefields in a model of the shallow sub-surface at the InSight landing site in Elysium Planitia and demonstrate how the high-frequency Rayleigh wave ellipticity can be extracted from these data and inverted for shallow structure. We find that, depending on model parameters, higher mode ellipticity information can be extracted from single-station data, which significantly reduces uncertainties in inversion. Though the data are most sensitive to properties of the upper-most layer and show a strong trade-off between layer depth and velocity, it is possible to estimate the velocity and thickness of the sub-regolith layer by using reasonable constraints on regolith properties. Model parameters are best constrained if either higher mode data can be used or additional constraints on regolith properties from seismic analysis of the hammer strokes of InSight’s heat flow probe HP3 are available. In addition, the Rayleigh wave ellipticity can distinguish between models with a constant regolith velocity and models with a velocity increase in the regolith, information which is difficult to obtain otherwise. KW - Mars KW - Interior KW - Seismology KW - Regoliths Y1 - 2017 U6 - https://doi.org/10.1007/s11214-016-0300-1 SN - 0038-6308 SN - 1572-9672 VL - 211 SP - 339 EP - 382 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Schulze-Makuch, Dirk A1 - Wagner, Dirk A1 - Kounaves, Samuel P. A1 - Mangelsdorf, Kai A1 - Devine, Kevin G. A1 - de Vera, Jean-Pierre A1 - Schmitt-Kopplin, Philippe A1 - Grossart, Hans-Peter A1 - Parro, Victor A1 - Kaupenjohann, Martin A1 - Galy, Albert A1 - Schneider, Beate A1 - Airo, Alessandro A1 - Froesler, Jan A1 - Davila, Alfonso F. A1 - Arens, Felix L. A1 - Caceres, Luis A1 - Cornejo, Francisco Solis A1 - Carrizo, Daniel A1 - Dartnell, Lewis A1 - DiRuggiero, Jocelyne A1 - Flury, Markus A1 - Ganzert, Lars A1 - Gessner, Mark O. A1 - Grathwohl, Peter A1 - Guan, Lisa A1 - Heinz, Jacob A1 - Hess, Matthias A1 - Keppler, Frank A1 - Maus, Deborah A1 - McKay, Christopher P. A1 - Meckenstock, Rainer U. A1 - Montgomery, Wren A1 - Oberlin, Elizabeth A. A1 - Probst, Alexander J. A1 - Saenz, Johan S. A1 - Sattler, Tobias A1 - Schirmack, Janosch A1 - Sephton, Mark A. A1 - Schloter, Michael A1 - Uhl, Jenny A1 - Valenzuela, Bernardita A1 - Vestergaard, Gisle A1 - Woermer, Lars A1 - Zamorano, Pedro T1 - Transitory microbial habitat in the hyperarid Atacama Desert JF - Proceedings of the National Academy of Sciences of the United States of America KW - habitat KW - aridity KW - microbial activity KW - biomarker KW - Mars Y1 - 2018 U6 - https://doi.org/10.1073/pnas.1714341115 SN - 0027-8424 VL - 115 IS - 11 SP - 2670 EP - 2675 PB - National Acad. of Sciences CY - Washington ER - TY - GEN A1 - de Vera, Jean-Pierre Paul A1 - Alawi, Mashal A1 - Backhaus, Theresa A1 - Baque, Mickael A1 - Billi, Daniela A1 - Boettger, Ute A1 - Berger, Thomas A1 - Bohmeier, Maria A1 - Cockell, Charles A1 - Demets, Rene A1 - de la Torre Noetzel, Rosa A1 - Edwards, Howell A1 - Elsaesser, Andreas A1 - Fagliarone, Claudia A1 - Fiedler, Annelie A1 - Foing, Bernard A1 - Foucher, Frederic A1 - Fritz, Jörg A1 - Hanke, Franziska A1 - Herzog, Thomas A1 - Horneck, Gerda A1 - Hübers, Heinz-Wilhelm A1 - Huwe, Björn A1 - Joshi, Jasmin Radha A1 - Kozyrovska, Natalia A1 - Kruchten, Martha A1 - Lasch, Peter A1 - Lee, Natuschka A1 - Leuko, Stefan A1 - Leya, Thomas A1 - Lorek, Andreas A1 - Martinez-Frias, Jesus A1 - Meessen, Joachim A1 - Moritz, Sophie A1 - Moeller, Ralf A1 - Olsson-Francis, Karen A1 - Onofri, Silvano A1 - Ott, Sieglinde A1 - Pacelli, Claudia A1 - Podolich, Olga A1 - Rabbow, Elke A1 - Reitz, Günther A1 - Rettberg, Petra A1 - Reva, Oleg A1 - Rothschild, Lynn A1 - Garcia Sancho, Leo A1 - Schulze-Makuch, Dirk A1 - Selbmann, Laura A1 - Serrano, Paloma A1 - Szewzyk, Ulrich A1 - Verseux, Cyprien A1 - Wadsworth, Jennifer A1 - Wagner, Dirk A1 - Westall, Frances A1 - Wolter, David A1 - Zucconi, Laura T1 - Limits of life and the habitability of Mars BT - the ESA space experiment BIOMEX on the ISS T2 - Astrobiology N2 - BIOMEX (BIOlogy and Mars EXperiment) is an ESA/Roscosmos space exposure experiment housed within the exposure facility EXPOSE-R2 outside the Zvezda module on the International Space Station (ISS). The design of the multiuser facility supports-among others-the BIOMEX investigations into the stability and level of degradation of space-exposed biosignatures such as pigments, secondary metabolites, and cell surfaces in contact with a terrestrial and Mars analog mineral environment. In parallel, analysis on the viability of the investigated organisms has provided relevant data for evaluation of the habitability of Mars, for the limits of life, and for the likelihood of an interplanetary transfer of life (theory of lithopanspermia). In this project, lichens, archaea, bacteria, cyanobacteria, snow/permafrost algae, meristematic black fungi, and bryophytes from alpine and polar habitats were embedded, grown, and cultured on a mixture of martian and lunar regolith analogs or other terrestrial minerals. The organisms and regolith analogs and terrestrial mineral mixtures were then exposed to space and to simulated Mars-like conditions by way of the EXPOSE-R2 facility. In this special issue, we present the first set of data obtained in reference to our investigation into the habitability of Mars and limits of life. This project was initiated and implemented by the BIOMEX group, an international and interdisciplinary consortium of 30 institutes in 12 countries on 3 continents. Preflight tests for sample selection, results from ground-based simulation experiments, and the space experiments themselves are presented and include a complete overview of the scientific processes required for this space experiment and postflight analysis. The presented BIOMEX concept could be scaled up to future exposure experiments on the Moon and will serve as a pretest in low Earth orbit. KW - EXPOSE-R2 KW - BIOMEX KW - Habitability KW - Limits of life KW - Extremophiles KW - Mars Y1 - 2019 U6 - https://doi.org/10.1089/ast.2018.1897 SN - 1531-1074 SN - 1557-8070 VL - 19 IS - 2 SP - 145 EP - 157 PB - Liebert CY - New Rochelle ER -