Реклама Google — средство выживания форумов :)
To decipher the complex lunar nitrogen archive, we have performed a series of microscopic N isotopic analyses at CRPG-Nancy aiming to precisely characterise the possible end-members contained in the lunar regoliths. Hashizume et al. (2000), using an ion microprobe, identified the N isotopic composition of the SW from the surface 100 nanometer layers of lunar regolith grains. The SW-N, associated with D-free H, a strong proof for its solar origin, showed a d15N value as low as –240 ‰, whereas non-solar N correlated with D-rich H possessed positive d15N values, as high as +50 ‰. Here in this study, we performed single mineral grain N-Ar isotope analyses to further tackle this problem. We analysed single grains, mostly of ~200 mm sized ilmenite, from Apollo 17 samples 71501, 79035 and 79135.
Experimental: In Nancy, a mass spectrometry system to analyse the isotopic composition of extremely small quantities of nitrogen has been developed, whose full detail is published elsewhere (Hashizume and Marty, 2001; Wieler et al., 1999). We analyse the N and Ar (38Ar & 36Ar) isotopic composition of the gas extracted from a single 200 mm sized ilmenite grain. The gas is extracted from single grains with a CO2 laser in CW mode to minimize the blank gas. Stepwise analyses are performed by controlling the power of the laser. Though the emperature control is not accurate (presumably around 100 oC), we can constantly control the release of gas components: >90 % of the trapped gas is released at low temperature (600-1000 oC), while >90 % of the cosmogenic gas is released during the
final fusion step.
Metallogeny Laboratoy has enabled grain-by-grain analysis of the isotopic compositions of the rare gases and nitrogen contained in about ten samples of lunar soil provided to CRPG by NASA to be carried out. This method has demonstrated the diversity of nitrogen sources present on the lunar surface: the solar wind on the one hand and meteorite or comet material on the other hand, added to the Moon during impacts. Analyses carried out with CRPG’s 1270 ion probe have lifted the veil over these sources.
We have measured by ion microprobe the depth profile of the carbon isotopic composition in mineral grains from lunar regolith sample 79035.
...
Ion probe analyses were performed at the Centre de Recherches Pe´trographiques et Ge´ochimiques (CRPG)-CNRS (Nancy, France), using the Cameca ims-1270
After beginning her career at the CEA (Commission for Atomic Energy) where the results of her research led the way towards the reconstruction of our climate and environment, Liliane Merlivat then worked on lunar samples from Nasa’s Apollo program.
VIENNA, 11 June (UN Information Service) – A piece of rock from the Moon is being lent to the United Nations at Vienna by the United States of America’s National Aeronautics and Space Administration (NASA). The lunar sample, which is about the size of a golf ball, will be the centrepiece of the UN Office for Outer Space Affairs (OOSA) Space Exhibit inside the Vienna International Centre.
The Moon rock will be the biggest piece in Austria and only the second piece of the Moon in the country. It is being presented today (11 June 2002) to the United Nations Director-General of the United Nations Office at Vienna, Antonio Maria Costa by the Ambassador of the US Mission to International Organizations in Vienna, Kenneth C. Brill.
Lunar sample 15459,6 (014) is a 160-gram fragment of a 4.8kg Moon rock collected by US astronaut James Irwin during the Apollo 15 mission which landed on the Moon on 30 July 1971. During the mission the astronauts used a Lunar Roving Vehicle to travel nearly five kilometres from their Lunar Module, Falcon.
This large rock has been used to prepare 13 lunarsample displays, one of which is illustrated in figure 23. These are located in Edmonton, Geneva, Oakland,
Yorba Linda, Denver, Washington D.C., Illinois, Kansas, Boston, Michigan, Philadelphia, Austin and Utah. Three thin sections of 15555 are also on display.
Centre at the Complex has a piece of Moon rock weighing 142 grams, presented to it by astronaut John Young, which is the largest piece of Moon rock outside the United States.
Редакционная аннотация
В книге изложены результаты последних исследований минералов лунного грунта, доставленного на Землю в 1970-х годах советскими автоматическими станциями, выполненные с использованием аналитического высоколокального оборудования последнего поколения. Особенно результативными оказались поиски в лунном реголите тонкодисперсных фаз рудных минералов с помощью аналитических сканирующих микроскопов. В результате 30 минералов и минеральных фаз обнаружены на Луне впервые, а половина из них выявлены впервые в природе. Отмечен факт наличия удивительно большого количества микрочастиц самородных минералов и их соединений в предельно малых объемах изучаемых проб. Есть основания предполагать участие в процессах лунного минералообразования ранее не известных механизмов, в том числе двухстадийного кластерного роста из газовой фазы и фракционирования редкоземельных элементов.
Для специалистов в области минералогии и планетологии.