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201.
J. Gómez-Elvira C. Armiens L. Casta?er M. Domínguez M. Genzer F. Gómez R. Haberle A.-M. Harri V. Jiménez H. Kahanp?? L. Kowalski A. Lepinette J. Martín J. Martínez-Frías I. McEwan L. Mora J. Moreno S. Navarro M. A. de Pablo V. Peinado A. Pe?a J. Polkko M. Ramos N. O. Renno J. Ricart M. Richardson J. Rodríguez-Manfredi J. Romeral E. Sebastián J. Serrano M. de?la Torre Juárez J. Torres F. Torrero R. Urquí L. Vázquez T. Velasco J. Verdasca M.-P. Zorzano J. Martín-Torres 《Space Science Reviews》2012,170(1-4):583-640
The Rover Environmental Monitoring Station (REMS) will investigate environmental factors directly tied to current habitability at the Martian surface during the Mars Science Laboratory (MSL) mission. Three major habitability factors are addressed by REMS: the thermal environment, ultraviolet irradiation, and water cycling. The thermal environment is determined by a mixture of processes, chief amongst these being the meteorological. Accordingly, the REMS sensors have been designed to record air and ground temperatures, pressure, relative humidity, wind speed in the horizontal and vertical directions, as well as ultraviolet radiation in different bands. These sensors are distributed over the rover in four places: two booms located on the MSL Remote Sensing Mast, the ultraviolet sensor on the rover deck, and the pressure sensor inside the rover body. Typical daily REMS observations will collect 180 minutes of data from all sensors simultaneously (arranged in 5 minute hourly samples plus 60 additional minutes taken at times to be decided during the course of the mission). REMS will add significantly to the environmental record collected by prior missions through the range of simultaneous observations including water vapor; the ability to take measurements routinely through the night; the intended minimum of one Martian year of observations; and the first measurement of surface UV irradiation. In this paper, we describe the scientific potential of REMS measurements and describe in detail the sensors that constitute REMS and the calibration procedures. 相似文献
202.
Rabbow E Rettberg P Barczyk S Bohmeier M Parpart A Panitz C Horneck G von Heise-Rotenburg R Hoppenbrouwers T Willnecker R Baglioni P Demets R Dettmann J Reitz G 《Astrobiology》2012,12(5):374-386
The multi-user facility EXPOSE-E was designed by the European Space Agency to enable astrobiology research in space (low-Earth orbit). On 7 February 2008, EXPOSE-E was carried to the International Space Station (ISS) on the European Technology Exposure Facility (EuTEF) platform in the cargo bay of Space Shuttle STS-122 Atlantis. The facility was installed at the starboard cone of the Columbus module by extravehicular activity, where it remained in space for 1.5 years. EXPOSE-E was returned to Earth with STS-128 Discovery on 12 September 2009 for subsequent sample analysis. EXPOSE-E provided accommodation in three exposure trays for a variety of astrobiological test samples that were exposed to selected space conditions: either to space vacuum, solar electromagnetic radiation at >110?nm and cosmic radiation (trays 1 and 3) or to simulated martian surface conditions (tray 2). Data on UV radiation, cosmic radiation, and temperature were measured every 10?s and downlinked by telemetry. A parallel mission ground reference (MGR) experiment was performed on ground with a parallel set of hardware and samples under simulated space conditions. EXPOSE-E performed a successful 1.5-year mission in space. 相似文献
203.
Fairén AG Davila AF Lim D Bramall N Bonaccorsi R Zavaleta J Uceda ER Stoker C Wierzchos J Dohm JM Amils R Andersen D McKay CP 《Astrobiology》2010,10(8):821-843
Mars has undergone three main climatic stages throughout its geological history, beginning with a water-rich epoch, followed by a cold and semi-arid era, and transitioning into present-day arid and very cold desert conditions. These global climatic eras also represent three different stages of planetary habitability: an early, potentially habitable stage when the basic requisites for life as we know it were present (liquid water and energy); an intermediate extreme stage, when liquid solutions became scarce or very challenging for life; and the most recent stage during which conditions on the surface have been largely uninhabitable, except perhaps in some isolated niches. Our understanding of the evolution of Mars is now sufficient to assign specific terrestrial environments to each of these periods. Through the study of Mars terrestrial analogues, we have assessed and constrained the habitability conditions for each of these stages, the geochemistry of the surface, and the likelihood for the preservation of organic and inorganic biosignatures. The study of these analog environments provides important information to better understand past and current mission results as well as to support the design and selection of instruments and the planning for future exploratory missions to Mars. 相似文献
204.
M.K. Griffiths V. Fedun R. Erdélyi R. Zheng 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(2):720-737
The solar atmosphere exhibits a diverse range of wave phenomena, where one of the earliest discovered was the five-minute global acoustic oscillation, also referred to as the p-mode. The analysis of wave propagation in the solar atmosphere may be used as a diagnostic tool to estimate accurately the physical characteristics of the Sun’s atmospheric layers.In this paper, we investigate the dynamics and upward propagation of waves which are generated by the solar global eigenmodes. We report on a series of hydrodynamic simulations of a realistically stratified model of the solar atmosphere representing its lower region from the photosphere to low corona. With the objective of modelling atmospheric perturbations, propagating from the photosphere into the chromosphere, transition region and low corona, generated by the photospheric global oscillations the simulations use photospheric drivers mimicking the solar p-modes. The drivers are spatially structured harmonics across the computational box parallel to the solar surface. The drivers perturb the atmosphere at 0.5?Mm above the bottom boundary of the model and are placed coincident with the location of the temperature minimum. A combination of the VALIIIC and McWhirter solar atmospheres are used as the background equilibrium model.We report how synthetic photospheric oscillations may manifest in a magnetic field free model of the quiet Sun. To carry out the simulations, we employed the magnetohydrodynamics code, SMAUG (Sheffield MHD Accelerated Using GPUs).Our results show that the amount of energy propagating into the solar atmosphere is consistent with a model of solar global oscillations described by Taroyan and Erdélyi (2008) using the Klein-Gordon equation. The computed results indicate a power law which is compared to observations reported by Ireland et al. (2015) using data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly. 相似文献
205.
Vladimiro Noce Davide Loreggia Gerardo Capobianco Silvano Fineschi Alessandro Bemporad Marta Casti Steven Buckley Marco Romoli Mauro Focardi Massimiliano Belluso Cédric Thizy Aline Hermans Damien Galano Jorg Versluys 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(11):3807-3818
PROBA-3 is an ESA mission aimed at the demonstration of formation flying performance of two satellites that will form a giant coronagraph in space. The first spacecraft will host a telescope imaging the solar corona in visible light, while the second, the external occulter, will produce an artificial eclipse. This instrument is named ASPIICS (Association of Spacecraft for Polarimetric and Imaging Investigation of the Corona of the Sun). To accomplish the payload's scientific tasks, PROBA-3 will ensure sub-millimeter reciprocal positioning of its two satellites using closed-loop on-board metrology. Several metrology systems will be used and the Shadow Position Sensor (SPS) subsystem senses the penumbra around the instrument aperture and returns the 3-D displacement of the coronagraph satellite, with respect to its nominal position, by running a dedicated algorithm. In this paper, we describe how the SPS works and the choices made to accomplish the mission objectives. 相似文献
206.
G. M. Martínez C. N. Newman A. De Vicente-Retortillo E. Fischer N. O. Renno M. I. Richardson A. G. Fairén M. Genzer S. D. Guzewich R. M. Haberle A.-M. Harri O. Kemppinen M. T. Lemmon M. D. Smith M. de la Torre-Juárez A. R. Vasavada 《Space Science Reviews》2017,212(1-2):295-338
We analyze the complete set of in-situ meteorological data obtained from the Viking landers in the 1970s to today’s Curiosity rover to review our understanding of the modern near-surface climate of Mars, with focus on the dust, CO2 and H2O cycles and their impact on the radiative and thermodynamic conditions near the surface. In particular, we provide values of the highest confidence possible for atmospheric opacity, atmospheric pressure, near-surface air temperature, ground temperature, near-surface wind speed and direction, and near-surface air relative humidity and water vapor content. Then, we study the diurnal, seasonal and interannual variability of these quantities over a span of more than twenty Martian years. Finally, we propose measurements to improve our understanding of the Martian dust and H2O cycles, and discuss the potential for liquid water formation under Mars’ present day conditions and its implications for future Mars missions. Understanding the modern Martian climate is important to determine if Mars could have the conditions to support life and to prepare for future human exploration. 相似文献
207.
Parro V Fernández-Remolar D Rodríguez-Manfredi JA Cruz-Gil P Rivas LA Ruiz-Bermejo M Moreno-Paz M García-Villadangos M Gómez-Ortiz D Blanco-López Y Menor-Salván C Prieto-Ballesteros O Gómez-Elvira J 《Astrobiology》2011,11(1):29-44
The particular mineralogy formed in the acidic conditions of the Río Tinto has proven to be a first-order analogue for the acid-sulfate aqueous environments of Mars. Therefore, studies about the formation and preservation of biosignatures in the Río Tinto will provide insights into equivalent processes on Mars. We characterized the biomolecular patterns recorded in samples of modern and old fluvial sediments along a segment of the river by means of an antibody microarray containing more than 200 antibodies (LDCHIP200, for Life Detector Chip) against whole microorganisms, universal biomolecules, or environmental extracts. Samples containing 0.3-0.5?g of solid material were automatically analyzed in situ by the Signs Of LIfe Detector instrument (SOLID2), and the results were corroborated by extensive analysis in the laboratory. Positive antigen-antibody reactions indicated the presence of microbial strains or high-molecular-weight biopolymers that originated from them. The LDCHIP200 results were quantified and subjected to a multivariate analysis for immunoprofiling. We associated similar immunopatterns, and biomolecular markers, to samples with similar sedimentary age. Phyllosilicate-rich samples from modern fluvial sediments gave strong positive reactions with antibodies against bacteria of the genus Acidithiobacillus and against biochemical extracts from Río Tinto sediments and biofilms. These samples contained high amounts of sugars (mostly polysaccharides) with monosaccharides like glucose, rhamnose, fucose, and so on. By contrast, the older deposits, which are a mix of clastic sands and evaporites, showed only a few positives with LDCHIP200, consistent with lower protein and sugar content. We conclude that LDCHIP200 results can establish a correlation between microenvironments, diagenetic stages, and age with the biomarker profile associated with a sample. Our results would help in the search for putative martian biomarkers in acidic deposits with similar diagenetic maturity. Our LDCHIP200 and SOLID-like instruments may be excellent tools for the search for molecular biomarkers on Mars or other planets. 相似文献
208.
Isotopic ratios in comets provide keys for the understanding of the origin of cometary material, and the physical and chemical
conditions in the early Solar Nebula. We review here measurements acquired on the D/H, 12C/13C, 16O/18O, 14N/15N, 32S/34S ratios in dust and gases, and discuss their cosmogonic implications. The prospects for future measurements from cometary
space missions and remote sensing observations at millimeter and submillimeter wavelengths are presented.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
209.
J.-P. Bibring P. Lamy Y. Langevin A. Soufflot M. Berthé J. Borg F. Poulet S. Mottola 《Space Science Reviews》2007,128(1-4):397-412
CIVA (Comet Infrared and Visible Analyser) is an integrated set of imaging instruments, designed to characterize the 360∘ panorama (CIVA-P) as seen from the Rosetta Lander Philae, and to study surface and subsurface samples (CIVA-M). CIVA-P is
a panoramic stereo camera, while CIVA-M is an optical microscope coupled to a near infrared microscopic hyperspectral imager.
CIVA shares a common Imaging Main Electronics (IME) with ROLIS. CIVA-P will characterize the landing site, with an angular
sampling (IFOV) of 1.1 mrad: each pixel will image a 1 mm size feature at the distance of the landing legs, and a few metres
at the local horizon. The panorama will be mapped by 6 identical miniaturized micro-cameras covering contiguous FOV, with
their optical axis 60∘ apart. Stereoscopic capability will be provided by an additional micro-camera, identical to and co-aligned with one of the
panoramic micro-camera, with its optical axis displaced by 10 cm. CIVA-M combines two ultra-compact and miniaturised microscopes,
one operating in the visible and one constituting an IR hyperspectral imaging spectrometer: they will characterize, by non-destructive
analyses, the texture, the albedo, the molecular and the mineralogical composition of each of the samples provided by the
Sample Drill and Distribution (SD2) system. For the optical microscope, the spatial sampling is 7 μm; for the IR, the spectral range (1–4 μm) and the spectral sampling (5 nm) have been chosen to allow identification of most minerals, ices and organics, on each
pixel, 40 μm in size. After being studied by CIVA, the sample could be analysed by a subsequent experiment (PTOLEMY and/or COSAC). The
process would be repeated for each sample obtained at different depths and/or locations. 相似文献
210.
Thér‘se Encrenaz 《Space Science Reviews》2005,116(1-2):99-119
Measurements of the chemical composition of the giant planets provide clues of their formation and evolution processes. According
to the currently accepted nucleation model, giant planets formed from the initial accretion of an icy core and the capture
of the protosolar gas, mosly composed of hydrogen and helium. In the case of Jupiter and Saturn (the gaseous giants), this
gaseous component dominates the composition of the planet, while for Uranus and Neptune (the icy giants) it is only a small
fraction of the total mass. The measurement of elemental and isotopic ratios in the giant planets provides key diagnostics
of this model, as it implies an enrichment in heavy elements (as well as deuterium) with respect to the cosmic composition.
Neutral atmospheric constituents in the giant planets have three possible sources: (1) internal (fromthe bulk composition
of the planet), (2) photochemical (fromthe photolysis ofmethane) and(3) external (from meteoritic impacts, of local or interplanetary
origin). This paper reviews our present knowledge about the atmospheric composition in the giant planets, and their elemental
and istopic composition. Measurements concerning key parameters, like C/H, D/H or rare gases in Jupiter, are analysed in detail.
The conclusion addresses open questions and observations to be performed in the future. 相似文献