81 research outputs found
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MoonLITE – Technological feasibility of the penetrator concept
Introduction: While the surface missions to the Moon of the 1960s and 1970s achieved a great deal, scientifically a great deal was also left unresolved. The recent plethora of lunar missions (flown or proposed) reflects resurgence in interest in the Moon, not only in its own right, but also as a record of the formation of the Earth-Moon System and the interplanetary environment at 1 AU. Results from orbiter missions have indicated the possible presense of ice within permanently shaded craters at the lunar poles [1] – a situation that, if confirmed, will have profound impacts on lunar exploration
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In situ radiometric dating on mars: investigation of the feasibility of K-Ar dating using flight-type mass and X-ray spectrometers
The absolute chronology of Mars is poorly known and as a consequence a key science aim is to perform accurate radiometric dating of martian geological materials. The scientific benefits of in situ radiometric dating are significant and arguably of most importance is the calibration of the martian cratering rate, similar to what has been achieved for the Moon, to reduce the large uncertainties on absolute boundary ages of martian epochs. The Beagle 2 Mars lander was capable of performing radiometric date measurements of rocks using the analyses from two instruments in its payload: (i) the X-ray Spectrometer (XRS) and (ii) the Gas Analysis Package (GAP). We have investigated the feasibility of in situ radiometric dating using the K-Ar technique employing flight-like versions of the Beagle 2 instrumentation. The K-Ar ages of six terrestrial basalts were measured and compared to the ‘control’ Ar-Ar radiometric ages in the range 171 – 1141 Ma. The K content of each basalt was measured by the flight spare XRS and the 40Ar content using a laboratory analogue of the GAP. The K-Ar ages of five basalts broadly agreed with their corresponding Ar-Ar ages. For the final basalt, the 40Ar content was below the detection limit and so an age could not be derived. The precision of the K-Ar ages was ~30% on average. The conclusions from this study are that careful attention must be paid to improving the analytical performance of the instruments, in particular the accuracy and detection limits. The accuracy of the K and Ar measurements are the biggest source of uncertainty in the derived K-Ar age. Having investigated the technique using flight-type planetary instrumentation, we conclude that come of the principle challenges of conducting accurate in situ radiometric dating on Mars using instruments of these types include determining the sample mass, ensuring all the argon is liberated from the sample given the maximum achievable temperature of the mass spectrometer ovens, and argon loss and non-radiogenic argon in the samples analysed
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MoonLITE programmatic and technological update
MoonLITE is a proposed four penetrator lunar mission. Following a US/UK working group assessment, a science assessment and the first UK impact trials, a full mission-level phase A study has begun. A technological and programmatic update of the mission is given
Use of a coupled soil-root-leaf model to optimise phosphate fertiliser use efficiency in barley
Pathogenicity of benomyl-tolerant variants of Verticillium dahliae to strawberry, cv. Cambridge Vigour
The Effect on Verticillium Wilt of Strawberries of Plant Spacing, Fertilizer Application and Defoliation
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