SOLID3: a multiplex antibody microarray-based optical sensor instrument for in situ life detection in planetary exploration

The search for unequivocal signs of life on other planetary bodies is one of the major challenges for astrobiology. The failure to detect organic molecules on the surface of Mars by measuring volatile compounds after sample heating, together with the new knowledge of martian soil chemistry, has prompted the astrobiological community to develop new methods and technologies. Based on protein microarray technology, we have designed and built a series of instruments called SOLID (for "Signs Of LIfe Detector") for automatic in situ detection and identification of substances or analytes from liquid and solid samples (soil, sediments, or powder). Here, we present the SOLID3 instrument, which is able to perform both sandwich and competitive immunoassays and consists of two separate functional units: a Sample Preparation Unit (SPU) for 10 different extractions by ultrasonication and a Sample Analysis Unit (SAU) for fluorescent immunoassays. The SAU consists of five different flow cells, with an antibody microarray in each one (2000 spots). It is also equipped with an exclusive optical package and a charge-coupled device (CCD) for fluorescent detection. We demonstrated the performance of SOLID3 in the detection of a broad range of molecular-sized compounds, which range from peptides and proteins to whole cells and spores, with sensitivities at 1-2?ppb (ng?mL?1) for biomolecules and 10? to 103 spores per milliliter. We report its application in the detection of acidophilic microorganisms in the Río Tinto Mars analogue and report the absence of substantial negative effects on the immunoassay in the presence of 50?mM perchlorate (20 times higher than that found at the Phoenix landing site). Our SOLID instrument concept is an excellent option with which to detect biomolecules because it avoids the high-temperature treatments that may destroy organic matter in the presence of martian oxidants.     

On the origin of the grooves on Phobos

L-grooves are the consequence of layered structure of Phobos, which are made up of parallel layers of different composition or hardness.     

Cosmogony as an extrapolation of magnetospheric research

A theory of the origin and evolution of the Solar System (Alfvén and Arrhenius, 1975, 1976) which considered electromagnetic forces and plasma effects is revised in the light of new information supplied by space research. In situ measurements in the magnetospheres and solar wind have changed our views of basic properties of cosmic plasmas. These results can be extrapolated both outwards in space, to interstellar clouds, and backwards in time, to the formation of the solar system. The first extrapolation leads to a revision of some cloud properties which are essential for the early phases in the formation of stars and solar nebulae. The latter extrapolation makes possible to approach the cosmogonic processes by extrapolation of (rather) well-known magnetospheric phenomena.Pioneer-Voyager observations of the Saturnian rings indicate that essential parts of their structure are fossils from cosmogonic times. By using detailed information from these space missions, it seems possible to reconstruct certain events 4–5 billion years ago with an accuracy of a few percent. This will cause a change in our views of the evolution of the solar system.     

The Freja Hot Plasma Experiment—Instrument and first results

The Hot Plasma Experiment, F3H, on boardFreja is designed to measure auroral particle distribution functions with very high temporal and spatial resolution. The experiment consists of three different units; an electron spectrometer that measures angular and energy distributions simultaneously, a positive ion spectrometer that is using the spacecraft spin for three-dimensional measurements, and a data processing unit. The main scientific objective is to study positive ion heating perpendicular to the magnetic field lines in the auroral region. The high resolution measurements of different positive ion species and electrons have already provided important information on this process as well as on other processes at high latitudes. This includes for example high resolution observations of auroral particle precipitation features and source regions of positive ions during magnetic disturbances. TheFreja orbit with an inclination of 63° allows us to make detailed measurements in the nightside auroral oval during all disturbance levels. In the dayside, the cusp region is covered during magnetic disturbances. We will here present the instrument in some detail and some outstanding features in the particle data obtained during the first months of operation at altitudes around 1700 km in the northern hemisphere auroral region.     

Mental representation of spatial cues in microgravity: Writing and drawing tests

Humans have mental representation of their environment based on sensory information and experience. A series of experiments has been designed to allow the identification of disturbances in the mental representation of three-dimensional space during space flight as a consequence of the absence of the gravitational frame of reference. This NASA/ESA-funded research effort includes motor tests complemented by psychophysics measurements, designed to distinguish the effects of cognitive versus perceptual-motor changes due to microgravity exposure. Preliminary results have been obtained during the microgravity phase of parabolic flight. These results indicate that the vertical height of handwritten characters and drawn objects is reduced in microgravity compared to normal gravity, suggesting that the mental representation of the height of objects and the environment change during short-term microgravity. Identifying lasting abnormalities in the mental representation of spatial cues will establish the scientific and technical foundation for development of preflight and in-flight training and rehabilitative schemes, enhancing astronaut performance of perceptual-motor tasks, for example, interaction with robotic systems during exploration-class missions.     

How to evidence Primitive Life on an exo-Planet? — The DARWIN project

We report the concept of an IR observatory, with interferometric rejection, to search for Primitive Life on an extra-Solar Planet which has been proposed to the European Space Agency.     

Theories and Observations of Ion Energization and Outflow in the High Latitude Magnetosphere

A review is given of several mechanisms causing outflow at high latitudes of ionospheric ions to the terrestrial magnetosphere. The upward ion motion along the geomaagnetic field can be divided into several categories, including polar wind, bulk ion outflow in the auroral region, upwelling ions and ion conics and beams. More than one ion energization mechanism can be operating within each category, and a combination of categories is important for the total ion outflow.