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Sattler B.,University of Innsbruck | Storrie-Lombardi M.C.,Kinohi Institute | Foreman C.M.,Montana State University | Tilg M.,University of Innsbruck | Psenner R.,University of Innsbruck
Annals of Glaciology | Year: 2010

Laser-induced fluorescence emission (LIFE) images were obtained in situ from a 27 cm long ice core at Lake Fryxell, Antarctica. The excitation was accomplished with a simple 532 nm green laser pen light, and the fluorescence images were captured with a small compact digital camera. The targets for the experiment were mm-scale cryoconite assemblages found in the ice covers of this perennially frozen Antarctic lake. The fluorescence response originates from photo-pigments in cyanobacteriadominated cryoconite assemblages with phycoerythrin (PE) exhibiting the optimal target cross section. This inexpensive, low-mass, low-energy method avoids manipulation of the in situ habitat and individual target organisms and does not disturb the microbial community or the surrounding ice matrix. We establish the correlation between fluorescence intensity and PE concentration. We show that cryoconite fluorescence response does not appear to decrease with depth in the ice cover, in agreement with similar findings at Lake Untersee, a perennially ice-covered lake in Dronning Maud Land, Antarctica. Optical reflection and refraction events at the air/ice interface can complicate quantitative estimates of total pigment concentrations. Laser targeting of a single mm-scale cryoconite can result in multiple neighboring excitation events secondary to reflection and refraction phenomena in the multiple air/ice interface of the bubbles surrounding the primary target. Source


Storrie-Lombardi M.C.,Kinohi Institute | Hall A.P.,Harvey Mudd College | Hang S.,Harvey Mudd College | Lyzenga G.A.,Harvey Mudd College | And 5 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

On Earth, the ice of the lakes, glaciers, and caves of the cryosphere (from the ancient Greek word cryos, meaning "cold" or "ice") harbors rich, complex biotic communities. Ice cave habitats have been posited for the Mars cryosphere. Ice in such caves would protect microbes from UV, X-rays, and heavy particle radiation and might be accessible during robotic or astronaut missions. Detection of putative biota-rich ice will require in situ detection of biosignatures in cave walls, floor, and ceiling a few centimeters to tens of meters distant from the investigating rover or astronaut. We describe the development of a prototype for a non-destructive, non-contact device that rapidly generates reflectance and fluorescence images and a midline target profile of 960 reflectance and fluorescence spectra. Spectral Profiling and Imaging (SPI) requires no irreplaceable consumables and can be sufficiently miniaturized to be used by a single astronaut or a small robotic explorer. The current laboratory instrument is designated SPI2 since it generates data sets for two optical phenomena: reflectance and fluorescence. In final form SPI4 will be integrated with an autonomous rover and generate data for four optical phenomena: reflectance, fluorescence, Raman scattering, and circular polarization. SPI4 will be useful for the Remote Evaluation of Life in Ice Caves (R.E.L.I.C.) on planetary bodies whose distance from Earth prohibits real-time mission control. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE). Source


Groemer G.E.,Austrian Space Forum | Storrie-Lombardi M.,Kinohi Institute | Sattler B.,University of Innsbruck
Acta Astronautica | Year: 2011

As part of the "PolAres" research programme, we are investigating techniques to detect and reduce forward contamination of the Mars regolith during human exploration. We report here on the development of a spacesuit simulator-prototype dubbed "Aouda.X," document the inability of current technology to produce a static charge sufficient to minimize dust transport on the suit, and present preliminary results employing laser induced fluorescence emission (L.I.F.E.) techniques to monitor fluorescent microspherules as biological contamination proxies. © 2010 Elsevier Ltd. All rights reserved. Source


Tilg M.,University of Innsbruck | Storrie-Lombardi M.,Kinohi Institute | Kohstall C.,Institute of Quantum Physics | Trenkwalder A.,Institute of Quantum Physics | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

The cryosphere harbours diverse microbial communities which are contributing to the global carbon budget. Various ice ecosystems like ice covers of freshwater lakes, sea ice and supraglacial areas are highly sensitive to temperate rise due to resulting enhanced availability of liquid water which is the prerequisite for life. To assess the overall importance of these communities we require a non-invasive tool which provides high resolution measurements of photosynthetic pigments such as phycoerythrin. Here we present the preliminary calibration processes for L.I.F.E. (laser induced fluorescence emission). © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE). Source


Cousins C.R.,University College London | Cousins C.R.,Birkbeck College | Griffiths A.D.,University College London | Crawford I.A.,University College London | And 8 more authors.
Astrobiology | Year: 2010

The Panoramic Camera (PanCam) instrument will provide visible-near IR multispectral imaging of the ExoMars rover's surroundings to identify regions of interest within the nearby terrain. This multispectral capability is dependant upon the 12 preselected "geological" filters that are integrated into two wide-angle cameras. First devised by the Imager for Mars Pathfinder team to detect iron oxides, this baseline filter set has remained largely unchanged for subsequent missions (Mars Exploration Rovers, Beagle 2, Phoenix) despite the advancing knowledge of the mineralogical diversity on Mars. Therefore, the geological filters for the ExoMars PanCam will be redesigned to accommodate the astrobiology focus of ExoMars, where hydrated mineral terrains (evidence of past liquid water) will be priority targets. Here, we conduct an initial investigation into new filter wavelengths for the ExoMars PanCam and present results from tests performed on Mars analog rocks. Two new filter sets were devised: one with filters spaced every 50nm ("F1-12") and another that utilizes a novel filter selection method based upon hydrated mineral reflectance spectra ("F2-12"). These new filter sets, along with the Beagle 2 filter set (currently the baseline for the ExoMars PanCam), were tested on their ability to identify hydrated minerals and biosignatures present in Mars analog rocks. The filter sets, with varying degrees of ability, detected the spectral features of minerals jarosite, opaline silica, alunite, nontronite, and siderite present in these rock samples. None of the filter sets, however, were able to detect fossilized biomat structures and small (<2mm) mineralogical heterogeneities present in silica sinters. Both new filter sets outperformed the Beagle 2 filters, with F2-12 detecting the most spectral features produced by hydrated minerals and providing the best discrimination between samples. Future work involving more extensive testing on Mars analog samples that exhibit a wider range of mineralogies would be the next step in carefully evaluating the new filter sets. Key Words: Analogue-Biosignatures- Mars-Reflectance spectroscopy-Remote sensing. Astrobiology 10, 933-951. © Mary Ann Liebert, Inc. Source

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