High resolution surface analysis of basaltic grains to support transport mode estimation for Martian sediments

Surface micro-morphological features of Mars relevant basaltic grains were surveyed and found some features already known based on quart grains, but also some new ones were identified which might hep to separate fluvial and aeolian transport modes

Mars-Relevant Field Experiences in Morocco: The Importance of Spatial Scales and Subsurface Exploration

During field work at the Ibn Battuta Mars analogue sites, two research questions were analyzed: (1) How do we identify sampling sites using remote and local imaging and (2) what kind of information can be gained from shallow subsurface exploration? While remote images help in targeting field activities in general, the connection between observations at different spatial scales for different rocky desert terrain types is not well established; in this, focused comparison of remote in situ images of well-selected analogues would help a great deal. Dried up lake beds as discerned in remotely acquired data may not show signatures of past water activity, while shallow subsurface exploration could reveal the lacustrine period. Acquisition of several satellite images of the same terrain under different geometries would help to support the planning of such in situ work. The selection of appropriate sampling sites in fluvial settings could be improved by analyzing long, meter-high, open-air outcrops that formed during most recent fluvial episodes. Such settings are abundant on Earth and could be present on Mars but may be just below the resolution of available data. By using 20–30-cm-deep excavations, shallow subsurface exploration could reveal the last period of geological history that would have been unattainable by surface observation alone. Aggregates embedded in the original strata or from heavily pulverized samples could not be identified; only weakly fragmented samples viewed right after acquisition showed aggregates, and thus, the close-up imager (CLUPI) on the ExoMover might provide information on cementation-related aggregation on the observing plate before crushing. The mechanical separation of different size grains (mainly clays and attached minerals) would also support the identification of individual components. To maximize context information during subsurface exploration, rover imaging should be accomplished before crushing; however, currently planned imaging may not be ideal for this

N-Saccharinylmethyl ether

In the title mol­ecule [systematic name: 1,1,1′,1′-tetra­oxo-2,2′-(oxydimethyl­ene)bi(1,2-benzothia­zol-3-one)], C16H12N2O7S2, the benzisothia­zole ring systems are individually planar [maximum deviations of 0.0497 (13) and 0.0195 (19) Å] and their mean planes are inclined at a dihedral angle of 62.76 (4)°. The crystal structure is stabilized by weak inter­molecular C—H⋯O inter­actions. Two O atoms bonded to two S atoms and four aryl H atoms belonging to two symmetry-related mol­ecules lying about an inversion center form a hydrogen-bonded 10-membered ring with graph-set notation R 4 2(10)

2-(2-Oxo-2-phenyl­ethyl)-1,2-benziso­thia­zol-3(2H)-one 1,1-dioxide

In the title compound, C15H11NO4S, the benzothia­zole unit is essentially planar [maximum deviation = 0.0644 (14) Å for the N atom] and forms a dihedral angle 54.43 (6)° with the phenyl ring. In the crystal structure, weak bifurcated C—H⋯O hydrogen bonds involving the carbonyl O atoms as acceptors result in R 2 2(7) ring motifs

2-[2-(3-Chloro­phen­yl)-2-oxoeth­yl]-1,2-benzisothia­zol-3(2H)-one 1,1-dioxide

In the title compound, C15H10ClNO4S, the benzothia­zole ring system is essentially planar [maximum deviation = 0.0382 (13) Å for the N atom] and forms a dihedral angle of 74.43 (6)° with the chloro-substituted benzene ring. In the crystal structure, weak inter­molecular C—H⋯O hydrogen bonds form R 2 2(10) and R 2 2(16) ring motif

Characterization and first results of the planetary borehole-wall imager – methods to develop for in-situ exploration

Prototypes of borehole-wall imager instruments were developed and tested at a desert riverbed in Morocco and at a lake’s salty flat in the Atacama desert, to support the drilling activity of ExoMars rover. The onsite recorded borehole images contain information on the context that are lost during the sample acquisition. Benefits of the borehole-wall imaging is the easier maximal energy estimation of a fluvial flow, the detailed information on sedimentation and layering, especially the former existence of liquid water and its temporal changes, including paleo-flow direction estimation from grain imbrication direction. Benefits of laboratory analysis of the acquired samples are the better identification of mineral types, determination of the level of maturity of granular sediment, and identification of the smallest, wet weathered grains. Based on the lessons learned during the comparison of field and laboratory results, we demonstrate that recording the borehole-wall with optical instrument during/after drilling on Mars supports the paleo-environment reconstruction with such data that would otherwise be lost during the sample acquisition. Because of the lack of plate tectonism and the low geothermal gradient on Mars, even Ga old sediments provide observable features that are especially important for targeting Mars sample return and later crewed Mars missions

Methyl 3-oxo-2,3-dihydro-1,2-benzothia­zole-2-acetate 1,1-dioxide

The title mol­ecule, C10H9NO5S, is composed of two essentially planar units with a dihedral angle of 89.16 (6)° between them. In the crystal structure, there are weak inter­molecular C—H⋯O inter­actions resulting in dimeric pairs of mol­ecules about inversion centres and chains of mol­ecules extended along the a and c axes, thus stabilizing the structure. In addition, benzothia­zole rings lying parallel to each other with centroid–centroid distances of 3.679 (2) and 3.999 (2) Å indicate the existence of π–π stacking inter­actions

2-[(E)-3-Phenyl­prop-2-en­yl]-1,2-benzisothia­zol-3(2H)-one 1,1-dioxide

In the crystal structure of the title compound, C16H13NO3S, the benzisothia­zole group is almost planar (r.m.s. deviation for all non-H atoms excluding the two O atoms bonded to S = 0.009 Å). The dihedral angle between the fused ring and the terminal ring is 13.8 (1)°. In the crystal, mol­ecules are linked through inter­molecular C—H⋯O contacts forming a chain of mol­ecules along b

Wind-snow interactions at the Ojos del Salado region as a potential Mars analogue site in the Altiplano - Atacama desert region

The general characteristics and interactions happening at a unique, potential new Mars analogue site, located in the Altiplano and Atacama Desert region: the Ojos del Salado inactive volcano. The interaction between rare snowing events and strong winds transported large masses of porous volcanic grains there could produce decimeter - meter thick buried snow masses fast, shielded against sublimation for extended periods (years). Subsurface temperature logging suggests that water ice melting is rare and surface modification is dominated by desiccation of the cryosphere and wind activity – just like on Mars. The site contains decameter scale megaripples, which are unusual for Earth and also support the understanding of resemble features on Mars. The shallow subsurface analysis with Mars relevance is supported here by drilled cores of evaporitic sediments