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Outer space, the final frontier, is a hostile and unforgiving place for any form of life as we know it. The unique environment of space allows for a close simulation of Mars surface conditions that cannot be simulated as accurately on the Earth. For this experiment, we tested the resistance of Deinococcus radiodurans to survive exposure to simulated Mars-like conditions in low-Earth orbit for a prolonged period of time as part of the Biology and Mars experiment (BIOMEX) project. Special focus was placed on the integrity of the carotenoid deinoxanthin, which may serve as a potential biomarker to search for remnants of life on other planets. Survival was investigated by evaluating colony forming units, damage inflicted to the 16S rRNA gene by quantitative PCR, and the integrity and detectability of deinoxanthin by Raman spectroscopy. Exposure to space conditions had a strong detrimental effect on the survival of the strains and the 16S rRNA integrity, yet results show that deinoxanthin survives exposure to conditions as they prevail on Mars. Solar radiation is not only strongly detrimental to the survival and 16S rRNA integrity but also to the Raman signal of deinoxanthin. Samples not exposed to solar radiation showed only minuscule signs of deterioration. To test whether deinoxanthin is able to withstand the tested parameters without the protection of the cell, it was extracted from cell homogenate and exposed to high/low temperatures, vacuum, germicidal UV-C radiation, and simulated solar radiation. Results obtained by Raman investigations showed a strong resistance of deinoxanthin against outer space and Mars conditions, with the only exception of the exposure to simulated solar radiation. Therefore, deinoxanthin proved to be a suitable easily detectable biomarker for the search of Earth-like organic pigment-containing life on other planets.

Bidirectional measurements of the downward radiance, degree and plane of polarisation were performed with the high resolution spectrometers OVID and HiRES in the spectral range of 650 nm -830 urn on two different days with meteorologically different conditions. The measurements have shown that the spectral and bidirectional behaviour of the degree of polarisation is different for these two days, especially in the 02A band. It can be assumed that this behaviour is caused either by different aerosol types on these two days or by different height distributions of the aerosol types or by a combination of these two effects. To simulate the measured Stokes vector, first of all aerosol optical thickness and their height distribution were varied and different calculations were performed. . IntroductionAerosols play an important role in climate. To estimate the influence of aerosols on climate it is necessary to describe their global abundance, properties and height distribution. A possibility to retrieve the height distribution of aerosols globally is the use of passive remote sensing techniques in the visible and near infrared spectral region. But the results obtained from radiance measurements are still not satisfactory. A possibility to overcome this problem is the exploitation of the polarising properties of aerosols scattering radiation in the atmosphere. Measurements at Space shuttle in 1985 [1], [2], measurements from ground, balloon and plane with the spectropolarimeter POLDER [3] and theoretical analysis [4] showed the sensibility of polarisation to aerosol characteristics. First investigations of polarisation in the 02A band [51 indicated the dependence of the spectral behaviour of the degree of polarisation on the aerosol height distribution.In this article we present bidirectional and spectral measurements of the Stokes vector of the downward radiation in the spectral range of 650 nm -830 urn. We've analysed these measurements to derive qualitatively aerosol height distribution from the bidirectional and spectral behaviour of the degree of polarisation in the range of the 02A band. An interpretation of this behaviour is given as well as in terms of single scattering as in multiple scattering considerations. It is shown that the stronger change in the spectral behaviour in the 02A band is due to the aerosol height distribution. MeasurementsThe polarisation measurements were performed on May 1 1 ,1994 with the spectrometer OVID and on June 24, 1994 with the spectrometer HiRES on the roof of our institute in Berlin. The spectrometer OVID [6] covers the spectral range of 600 -830nm with a spectral resolution of 2nm if performing polarisation measurements. The field of view is 0.27°. The spectrometer HiRES is measuring in the spectral range of 650 -780nm with an spectral resolution of 0.3nm and a field of 0-81 94-1946-X/95/$6.00 SPIE Vol. 2582 / 13 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/21/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx

The question about the stability of certain biomolecules is directly connected to the life-detection missions aiming to search for past or present life beyond Earth. The extreme conditions experienced on extraterrestrial planet surface (e.g. Mars), characterized by ionizing and non-ionizing radiation, CO2-atmosphere and reactive species, may destroy the hypothetical traces of life. In this context, the study of the biomolecules behaviour after ionizing radiation exposure could provide support for the onboard instrumentation and data interpretation of the life exploration missions on other planets. Here, as a part of STARLIFE campaign, we investigated the effects of gamma rays on two classes of fungal biomolecules–nucleic acids and melanin pigments – considered as promising biosignatures to search for during the ‘in situ life-detection’ missions beyond Earth.

The Japanese MMX sample return mission to Phobos by JAXA will carry a Rover developed by CNES and DLR that will be deployed on Phobos to perform in-situ analysis of the Martian moon's surface properties. Past images of the surface of Phobos show that it is covered by a layer of regolith. However, the mechanical and compositional properties of this regolith are poorly constrained. In particular nothing is known regarding the particle sizes, their chemical composition, the packing density of the regolith as well as other frictional parameters and surface dynamics from current remote images. Understanding the properties and dynamics of the regolith in the low-gravity environment of Phobos is important to trace back its history and surface evolution. Moreover, this information is also important to support the interpretation of data obtained by instruments onboard the main spacecraft and to minimize the risks involved in the sampling by the spacecraft. The instruments onboard the Rover are an infrared radiometer (miniRad), a Raman spectrometer (RAX), two cameras looking forwards for navigation and science purposes (NavCams), and two cameras observing the flow of regolith around the rover wheels (WheelCams). The Rover will be deployed before the sampling of Phobos' surface by MMX spacecraft and will be the first rover driving on a Martian moon and in a low-gravity environment.