Viability of barley seeds after long-term exposure to outer side of international space station

Barley seeds were exposed to outer space for 13 months in a vented metal container without a climate control system to assess the risk of physiological and genetic mutation during long-term storage in space. The space-stored seeds (S0 generation), with an 82% germination rate in 50 seeds, lost about 20% of their weight after the exposure. The germinated seeds showed normal growth, heading, and ripening. The harvested seeds (S1 generation) also germinated and reproduced (S2 generation) as did the ground-stored seeds. The culm length, ear length, number of seed, grain weight, and fertility of the plants from the space-stored seeds were not significantly different from those of the ground-stored seeds in each of the S0 and S1 generation. Furthermore, the S1 and S2 space-stored seeds respectively showed similar β-glucan content to those of the ground-stored seeds. Amplified fragment length polymorphism analysis with 16 primer combinations showed no specific fragment that appears or disappears significantly in the DNA isolated from the barley grown from the space-stored seeds. Though these data are derived from nine S0 space-stored seeds in a single exposure experiment, the results demonstrate the preservation of barley seeds in outer space for 13 months without phenotypic or genotypic changes and with healthy and vigorous growth in space.     

Exobiological investigations on Russian spacecrafts

To investigate the possibility of prebiotic synthesis of organic molecules in open space, conditions involved irradiating nucleosides and inorganic phosphate during five Earth-orbiting Russian space missions that included Salut-7 (13- and 16-month missions), Mir, Bion-11, and Cosmos-2044. Dry films of samples were exposed from 2 weeks up to 16 months to the entire set of factors encountered in open space during Earth-orbiting missions. After each mission, products synthesized during flight and any compounds that remained undegraded were analyzed. The analyses demonstrated that increased flight duration led to the decay of both synthesized nucleotides and initial nucleosides. Corresponding laboratory experiments indicated that infrared radiation caused the greatest amount of decay to products of prebiotic reactions. Experiments revealed that 5'-mononucleotides were the main chemical products of the major derivatives synthesized of certain nucleosides. Exposure to ultraviolet (UV) C(145) was more effective than UVC(254) in producing a comparatively higher yield of mononucleotides, while the energy flux of the latter was one order of magnitude less (10(-7) as compared with 10(-6) for UVC(145)). In the course of the laboratory simulation experiments the heating of solid samples yielded the greatest production amount (6.34% for adenosine derivatives).     

多层月球模型的自转动力学与着陆探测

着重于寻找月核证据并将月核模型引入月球天平动理论中,探讨如何将多种空间探测技术应用于毫角秒精度的月球天平动观测,进而测定液态和固态月核参量。通过讨论多层月球的月球物理参数、流体核的几何与动力学椭率、松散黏滞的月幔,可获得月球相关详细信息与参量,这些参量对评估多层结构的月球自由天平动很重要。物理天平动的解析理论还可应用于未来多种月球工作中,期望在近代月球科学研究基础上能有进一步发展。     

Project “The Moon – 2012+”: Spin-orbital evolution,geophysics and selenodesy of the Moon

The Russian scientific project “The Moon – 2012+” is directed at solving fundamental problems of celestial mechanics, selenodesy and geophysics of the Moon through the pursuance of theoretical research and computer simulations of the following fields.     

Overview of Differential VLBI Observations of Lunar Orbiters in SELENE (Kaguya) for Precise Orbit Determination and Lunar Gravity Field Study

The Japanese lunar explorer SELENE (Kaguya), which was launched on September 14th, 2007, was the target of VLBI observations over the period November 2007 to June 2009. These observations were made in order to improve the lunar gravity field model, in particular the lower degree coefficients and the model near the limb. Differential VLBI Radio sources, called VRAD instruments, were on-board the subsatellites, Rstar (Okina) and Vstar (Ouna), and the radio signals were observed by the Japanese VERA (VLBI Exploration of Radio Astrometry) network, and an international VLBI network. Multi-frequency and same-beam VLBI techniques were utilized and were essential aspects of the successful observing program. Multi-frequency VLBI was employed in order to improve the accuracy of the orbit determination obtained from the phase delay from the narrow-band satellite signals, while the same-beam VLBI method was used to resolve the cycle ambiguity which is inherent in the multi-frequency VLBI method. The observations were made at three S-band frequencies (2212, 2218 and 2287 MHz), and one X-band frequency (8456 MHz). We have succeeded in correlating the recorded signals from Okina/Ouna, and we obtained phase delays with an accuracy of several pico-seconds at S-band.     

Microbial rock inhabitants survive hypervelocity impacts on Mars-like host planets: first phase of lithopanspermia experimentally tested

The scenario of lithopanspermia describes the viable transport of microorganisms via meteorites. To test the first step of lithopanspermia, i.e., the impact ejection from a planet, systematic shock recovery experiments within a pressure range observed in martian meteorites (5-50 GPa) were performed with dry layers of microorganisms (spores of Bacillus subtilis, cells of the endolithic cyanobacterium Chroococcidiopsis, and thalli and ascocarps of the lichen Xanthoria elegans) sandwiched between gabbro discs (martian analogue rock). Actual shock pressures were determined by refractive index measurements and Raman spectroscopy, and shock temperature profiles were calculated. Pressure-effect curves were constructed for survival of B. subtilis spores and Chroococcidiopsis cells from the number of colony-forming units, and for vitality of the photobiont and mycobiont of Xanthoria elegans from confocal laser scanning microscopy after live/dead staining (FUN-I). A vital launch window for the transport of rock-colonizing microorganisms from a Mars-like planet was inferred, which encompasses shock pressures in the range of 5 to about 40 GPa for the bacterial endospores and the lichens, and a more limited shock pressure range for the cyanobacterium (from 5-10 GPa). The results support concepts of viable impact ejections from Mars-like planets and the possibility of reseeding early Earth after asteroid cataclysms.