ABSTRACT
In this paper we present the concept of a robotic instrument for in situ luminescence dating of near-surface sediments on Mars. The scientific objectives and advantages to be gained from the development of such an instrument are described, and the challenges presented by the Mars surface environment to the design and operation of the instrument are outlined.
Subject(s)
Geologic Sediments/analysis , Luminescence , Mars , Robotics , Space Flight/instrumentation , Cosmic Radiation , Equipment Design , Evolution, Planetary , Extraterrestrial Environment , Protons , Solar Activity , Spacecraft/instrumentation , Specimen HandlingABSTRACT
Monolayer networks, obtained from murine spinal cord tissue and grown on a matrix of 64 photo-etched, indium-tin oxide (ITO) microelectrodes, can be electrically stimulated through such thin-film recording electrodes. Multichannel coordinated network activity can be evoked and spontaneous network activity can be modified by generation of additional, multichannel bursting. Although single pulses through 1 electrode may trigger network responses, networks generally react best to short trains of pulses. Response thresholds approximate standard physiological strength/duration relationships. Repetitive stimulation trains often generate network activity patterns akin to epileptiform activity. The ITO conductors remain stable for recording under warm saline for long periods of time (maximum test period: 8 months). However, most electrodes show a reduction in impedance after several thousand stimulus pulses. Electrode breakdown in the form of ITO oxidation and loss of light transmittance occurs before hydrolysis is observed but requires a combination of voltage levels and pulse lengths beyond that needed for effective network stimulation.
