Stardust microcrater residue compositional groups

Compositional groups are defined in residue from Stardust craters (1-9 Dc) by qualitative EDS. These compositional groups are being further studied by a FIB-SEM technique to determine representative residue compositions

Limiting stable currents in bounded electron and ion streams

The classical static analysis of the infinite planar diode has been extended to include the effects of finite transverse beam size. Simple expressions have been found for the increase in maximum stable current density over that of an infinite stream for finite cylindrical and strip streams flowing between plates of infinite diodes. The results are also given in terms of stream perveance. The effect of a nonuniform distribution of current across the stream is shown to be relatively small. Experimental values of maximum stable current agree with those obtained from the analysis. A further extension of the static analysis has been made to include the effects of additional conducting plane boundaries parallel to the stream motion. For length-to-width ratios L/D less than 0.25 the tube is adequately described by the results for the infinite planar diode and for L/D greater than 4, the infinitely-long drift tube theory suffices. At intermediate values of L/D, the maximum amount of current that can be stably passed through the tube is greater than that predicted by either asymptotic theory

Iron Oxide Grains in Stardust Track 121 Grains as Evidence of Comet Wild 2 Hydrothermal Alteration

Stardust Track 121 terminal grains contain Fe-oxide. These are consistent with the presence of hydrothermal alteration on the Comet Wild 2 parent body

Contributions for innovative institutional research quality assessment practices and processes

The urge for the achievement of excellence patterns in research has led higher education institutions to become more and more aware of their role in the process by putting their strategic emphasis on the development of assessment tools towards the monitoring and evaluation of research quality. We intend to review the lessons learned from current research assessment experiences and collect good practices and recommendations using semi-directed interviews with evaluation panel members, institutions’ representatives and researchers involved in the last UK’s Research Assessment Exercise. Our major aim is to present and discuss a set of guidelines as a first input for the design of an evaluation framework to evaluate and monitor the quality of research at an institutional level. We seek to add significantly to our understanding of what can be actually done using strategic planning to look forward in the areas of research engagement/resources and institutional culture, productivity/ performance and innovation, quality/merit and impact and sustainability/ support. Overall, the challenges of promoting research are discussed and strategies for its enhancement are included

Lithium and carbon isotopic fractionations between the alteration assemblages of Nakhla and Lafayette

Nakhla and Lafayette delta 7Li values for samples and extracts (4.1-14.2�) are consistent with brine evaporation. Relatively 13C-poor siderite in Lafayette suggests more than one carbon source was sampled

Revised target co-ordinates for the Beagle 2 lander

The revised, IAU 2000 target co-ordinates of the Mars Beagle 2 lander are 11.6oN, 90.75oE

Designing avionics for lasers & optoelectronics

Unlike imagery-based Earth observation (EO) which has become very widely and cheaply available, gravity sensing EO has not yet emerged from its fundamental science roots. The challenge therefore is to develop gravity sensing instruments that can replicate the success of widespread imagery based EO. There are three main gravity sensing mechanisms under investigation: laser ranging (e.g., GRACE-FO [1]); atom interferometers, which measure gravitation perturbations to the wavefunctions of individual atoms; and ‘relativistic geodesy’ which uses atomic clocks to measure the gravitational curvature of spacetime. All three of these measurement systems use stabilised lasers as their main enabling technology. However traditional laboratory laser systems struggle to meet the robustness, reliability, or low size, weight, and power (SWaP) requirements for use in space. A demonstrator was build that adapted telecommunications industry COTS components, and software radio FPGA/DSP techniques, to develop a new all-fibre space-qualified stabilised laser systems for geodesy that have equivalent performance to laboratory systems. This instrument was used to develop a 780 nm laser system that is stabilised to the Rubidium D2 line - the stabilised laser most commonly required by the quantum and atomic sensing field achieving sufficiently high laser performance for the laser system to be immediately useful for quantum applications (stability: 1-10 kHz, accuracy: 1 MHz); and in an ultra-compact package that has the potential to be used in space (1 litre, 0.5 kg, 10 W) [2]. This paper reports on the current student work that advances the instrument further towards a flight payload – and key avionics design considerations for future researchers. This takes lessons learnt from the ESA ESEO software radio payload in utilising ECSS design practices [3] to fabricate a robust and modular avionics back-end board that can operate with numerous front-end laser or opto-electronics configurations for different quantum applications. The new board consists of a single PCB containing circuitry for TT&C reporting of power supply and voltage conditioning, the current and temperature electronics needed to control a diode laser on orbit, interfaces for photo detectors and opto-electronics, and a high-speed analogue- to-digital conversion network centred around a FPGA. As an example, digital signal processing performed frequency-modulated spectroscopy on a warm Rubidium vapour using an all-fibre optical arrangement