A Long Term ISU-UNISA Partnership: The SHSSP

Since 2011, the Southern Hemisphere Space Studies Program (SHSSP) has been held six times in Adelaide, Australia. The last program, which ran from January 9 to February 10, 2017, saw the engagement of 39 participants from around the world and over 45 international experts, whose backgrounds encompassed the entire spectrum of disciplines relevant to space exploration, industry and technology. The participants had a broad range of experiences, being represented by undergraduate students all the way to professionals employed in national space agencies, and entrepreneurs. This provided an exciting mix of motivations and abilities, which clearly epitomised the purpose of the program: to expose highly achieving students in training as well as accomplished professionals to a proxy of the multidisciplinary and multifaceted environment typical of space enterprises. The international, intercultural, and interdisciplinary philosophy of the program was reflected in a diversity of lectures, hands-on workshops, public events and team exercises, delivered by experts from Australia, America, Asia and Europe. A capstone project on the small satellite revolution involving participants, faculty and consulting experts, was synthesised in a paper entitled ‘Small Sats Big Shift: Recommendations for the Global South”. The 2017 program was highly successful, and the five week live-in program, complemented by one optional week of intensive English as second language program carried out before the commencement of the SHSSP, is now an established educational offering of the International Space University - University of South Australia (UniSA) consortium, which is presently exploring longer term agreements to continue and expand this productive educational collaboration beyond the next program, to be held at UniSA in January-February 2018

Epidemiology and geographical distribution of enteric protozoan infections in Sydney, Australia

© 2014 S. Fletcher et al., 2014. Results: Frequently detected protozoa were Blastocystis spp. (57%), Giardia intestinalis (27%) and Dientamoeba fragilis (12%). The age distribution showed that the prevalence of protozoa decreased with age up to 24 years but increasing with age from 25 years onwards. The geographic provenance of the patients indicates that the majority of cases of Blastocystis (53.1%) are clustered in and around the Sydney City Business District, while pockets of giardiasis were identified in regional/rural areas. The distribution of cases suggests higher risk of protozoan infection may exist for some communities.Conclusions: These findings provide useful information for policy makers to design and tailor interventions to target high risk communities Follow-up investigation into the risk factors for giardiasis in regional/rural areas is needed.Background: Enteric protozoa are associated with diarrhoeal illnesses in humans; however there are no recent studies on their epidemiology and geographical distribution in Australia. This study describes the epidemiology of enteric protozoa in the state of New South Wales and incorporates spatial analysis to describe their distribution.Design and methods: Laboratory and clinical records from four public hospitals in Sydney for 910 patients, who tested positive for enteric protozoa over the period January 2007 - December 2010, were identified, examined and analysed. We selected 580 cases which had residence post code data available, enabling us to examine the geographic distribution of patients, and reviewed the clinical data of 252 patients to examine possible links between protozoa, demographic and clinical features

An Analysis of MARSIS Radar Flash Memory Data from Lunae Planum, Mars: Searching for Subsurface Structures

Lunae Planum is a Martian plain measuring approximately 1000 km in width and 2000 km in length, centered at coordinates 294°E-11°N. MOLA elevations range from +2500 m to +500 m in the south, gently sloping northward to -500 m. The plain is part of a belt of terrains located between the southern highlands and the northern lowlands, that are transitional in character (e.g., by elevation, age and morphology). These transitional terrains are poorly understood, in part because of their relative lack of major geomorphological features. They record however a very significant part of Mars's geologic history. The most evident features on Lunae Planum's Hesperian surface are regularly spaced, longitudinally striking, wrinkle ridges. These indicate the presence of blind thrust faults cutting through thick stacks of layers of volcanic or sedimentary rocks. The presence of fluidized ejecta craters scattered all over the region suggests also the presence of ice or volatiles in the subsurface. In a preliminary study of Lunae Planum's subsurface we used the Mars Express ground penetrating radar MARSIS dataset [1], in order to detect reflectors that could indicate the presence of fault planes or layering. Standard radargrams however, provided no evidence of changes in value of dielectric constant that could indicate possible geologic discontinuities or stratification of physically diverse materials. We thus started a new investigation based on processing of raw MARSIS data. Here we report on the preliminary results of this study. We searched the MARSIS archive for raw data stored in flash memory. When operating with flash storage, the radar collects 2 frequency bands along-track covering a distance = 100-250 km, depending on the orbiter altitude [2]. We found flash memory data from 24 orbits over the area. We processed the data focusing radar returns in off-nadir directions, to maximize the likelihood of detecting sloping subsurface structures, including those striking parallel to the Mars Express sub-polar orbits. We plan to follow this study by applying a new processor aimed at improving the resolution and signal to noise ratio of the data. [1] Caprarelli et al. (2017), LPSC 48, 1720. [2] Watters et al. (2017), LPSC 48, 1693

The Mars Australian Remote Virtual Experiment Laboratory (MARVEL): A MARSIS Research Platform Fostering STEM Education Excellence

MARVEL is a planetary research and STEM education virtual laboratory in its proof-of-concept stage. Here we present its underpinning STEM education concepts

Radar Sounding by MARSIS Over Lucus Planum, Mars

Probed by the MARSIS radar sounder, Lucus Planum is found to be laterally inhomogeneous, its central part consisting of denser, more radar-attenuating material

Interpretation of Radar Sounder MARSIS Data from Lucus Planum, Mars: A Complex Geological Setting

Lucus Planum (LP) is a Martian plain located in the central part of the Medusae Fossae Formation (MFF). This geological unit is composed of pyroclastic flows or airfall [1-2], and paleopolar deposits or atmospherically-deposited icy dust [3]. For more than a decade the MFF has been probed by the Mars Express MARSIS and Mars Reconnaissance Orbiter SHARAD synthetic-aperture low-frequency radars, which revealed that the dielectric permittivity of the MFF subsurface is consistent with either a substantial component of water ice or a low-density material [4-5]. Here we report the results of our investigation of Lucus Planum: we processed 238 MARSIS orbits acquired across an area approximately 750,000 km2 in extent, and identified the locations of subsurface reflectors in this plain to unprecedented detail. Our work revealed 97 reflectors, mostly concentrated in the eastern, SW and NW sectors of LP. By estimating the thicknesses of strata laying on top of a theoretical basal surface obtained by interpolation of MOLA elevations around the plain, and correlating them with the apparent depth calculated from the radar pulse return times, we were able to estimate the dielectric constants of subsurface materials in the three sectors. The calculated values of dielectric constant in the eastern and SW sectors were 2.3, suggesting the presence of highly porous material, possibly pyroclastic deposits, in agreement with earlier interpretations [5]. The value of dielectric constant in the NW sector was 4.5, implying the presence of denser materials. In the central area of the plain we obtained only a few strong echoes, related to shallow strata and pedestal craters. The subsurface layers here attenuate the radar pulses, suggesting a material with dielectric characteristics different than those at the margins of LP. Interpretation of these findings is not unique and more investigations are needed to conclusively establish the nature of deposits forming Lucus Planum, but the evidence clearly points to a complex sequence of events, involving different types of geological processes. [1] Tanaka (2000) Icarus, 144, 254-266. [2] Kerber et al (2011) Icarus, 216, 212-220. [3] Schultz & Lutz (1988) Icarus, 73, 91-141. [4] Watters et al (2007) Science, 318, 1125-1128. [5] Carter et al (2009) Icarus, 199, 295-302

The state of planetary science in Australia

A head-count of Australia-based scientists doing research in planetary science was performed in the context of the drafting of the Decadal Plan for Space Sciences [1]. This paper builds on those findings. A search of papers published by Australia-based scientists in the period 2005-2008 was performed. The search returned 91 papers published in international journals by scientists distributed in 7 groups, of which 6 are identified by the affiliations of the researchers, and one, termed Others, is composed of individuals working independently. Correspondence analysis performed on the data returned distinctive associations of the ANU, UNSW and Others groups with the subdisciplines of cosmochemistry, astrobiology and mission data analysis, respectively. These associations are interpreted as indicating clusters of activity that are, or have the potential to grow into, areas of high productivity. A minimalist model to support and organise activity in the potential cluster represented by the Others is presented here

Introducing and discussing a novel diagrammatic representation of impact crater dimensions

Impact craters on the surface of Mars are degraded by erosion and infilling due to combinations of geological processes. These result in modifications of relative crater dimensions, including diameter increase and reduction of rim-floor depths. In principle, the longer a crater is exposed to geological processes, the more pronounced the modifications. Visualization and analysis of these effects are achieved by plotting the measured depths (M) of impact craters vs the corresponding theoretical depths (predicted: P) calculated from the crater diameters using depth/. Diameter power laws. This type of diagram is referred to as MPD (measured depth vs predicted depth diagram). The advantage of using the MPD representation consists in the fact that the data plot along linear regressions, more easily interpreted than standard depth vs diameter diagrams.As an example of application of the method, the MPD was used to discriminate different generations of impact craters in Terra Sabaea into four groups: T0 (fresh craters), T1, T2 and T3 (from younger to older), all located on the most ancient geological unit in the area (Npld). Other units in the area are Hpl3 and Hr, impacted only by craters belonging to group T0, suggesting that these units are stratigraphically correlated. The data of 5 craters in superposition relationships with the eastern reaches of Evros Vallis, one of the major valley networks in the area, were plotted in the diagram and assigned each to a regression depending on the location of their data points in relation to the prediction bands of the regressions. The craters superposed to the valley all belonged to T0, indicating that Evros Vallis has the same relative age of units Hpl3 and Hr.A conceptual discussion of the results demonstrates that MPD statistics (a) are unaffected by the procedures used to acquire depths and diameters of impact craters and by the power laws used, and (b) can be interpreted irrespective of the sequence or combination of processes leading to modification of the crater morphometric data. These properties make the diagram a powerful statistical tool. © 2014 Elsevier Inc

A clinopyroxene-basalt geothermobarometry perspective of Columbia Plateau (NW-USA) Miocene magmatism

The origin of NW-USA Columbia River Basalt Group Miocene magmatism and its relation to tectonism has been widely debated and is still open to study. We investigated the pre-eruptive evolution of the magmas, to constrain pressures and temperatures of the ascending magmas, and plumbing conditions. We determined major element concentrations of 17-6 Ma tholeiites, and applied clinopyroxene - liquid geothermobarometry to calculate pre-eruptive pressures and temperatures. These ranged from 0 to 0.66 GPa and 1120 to 1222 °C, respectively, defining two age-related parallel trends in a P-T diagram. This indicates a consistent crustal evolution of the magmas, and records at least two distinct initial temperatures. Using clinopyroxene interdiffusion coefficients we estimated magma ascent speeds ≥ 0.6 km yr-1. Possible geological explanations for the calculated parameters are: lower-crust magma chamber processes; magmatism amd tectonism feedback consistent with an extensional environment. © 2005 Blackwell Publishing Ltd

Physical evolution of Grande Ronde Basalt magmas, Columbia River Basalt Group, north-western USA

In this paper we present what is, to the best of our knowledge, the first comprehensive study of clinopyroxenes and plagioclases contained in the flows of the Grande Ronde Basalt member of the Columbia River Basalt Group (northwestern USA). The rocks have MgO (wt%) <6, and trace amounts of Cr and Ni. About 56% of extracted solid containing normative clinopyroxene and plagioclase explains the liquid line of descent from the more mafic sample (MgO=5.89wt%) to the most evolved. The most ubiquitous phases in the basalts; are plagioclase and augite. Ilmenite and magnetite are accessories in all rocks. Olivine is present in small amount only in one sample (RT 89-7). Based on principles of Ca-Na plagioclase-liquid exchange, estimates of preeruptive magmatic water are <2.4wt%. From clinopyroxene-liquid equilibria, calculated pressures and temperatures of ascending magmas are between I atm and 0.617 GPa, and 1068°C and 1166°C, respectively. Compositions of magnetite-ilmenite pairs and olivine-clinopyroxene-oxide assemblages yield post-eruptive oxygen fugacities of △NNO =-1.923, and one pre-eruptive value of △NNO =-2.455. A simple model of asthenospheric melting and magma pending in the lower crust fits the physical parameters. © Springer-Verlag 2004