En la serie de cuadernos del seminario de la Universidad Nacional Autónoma de México, “Modernidad: versiones y dimensiones”, dirigido por Marta Lamas y que ha sido coordinado anteriormente por Raquel ...Serur y por su fundador Bolívar Echeverría, Andrés Luna Jiménez, un joven historiador, ha publicado un libro notable: Figuras de la crítica: la (de)formación del sujeto como problema histórico en Marcuse, Foucault y Butler. El libro contiene virtudes difíciles de alcanzar en la academia actual: muestra una clara voz autoral; un hilo argumental sostenido, profundo y, a la vez, pedagógico; y actualiza con sutileza los debates, los enfrenta y los coloca bajo una perspectiva abierta a la investigación filosófica contemporánea.
The works of popular Spanish film directors Julio Medem, Juan Jose Bigas Luna, and Jose Luis Guerin are newly appraised in relation to their engagement with alternative national and cinematic ...subjectivities. Their films examine the limitations of the cinematic gaze, as the author shows, highlighting the ways in which these directors make recourse to hybridity, contact, and interface to overcome the binary power dynamic previously thought to be a feature of cinema. This book explores their status as solely "Spanish" filmmakers while focusing on their diverse and immensely creative output, offering new readings that engage with current debates in visual culture surrounding psychoanalytic theory, phenomenology, and theories of documentary practice.
•Statistics of 269 K–Ar datings of lunar highland returned samples are reviewed.•These are compared against 94 datings of meteoritic highland rocks from 21 localities.•Cumulative effect of impact ...gardening on presence of melt at surface is modelled.•Combined modelling and analysis contradicts idea of a short terminal cataclysm.
This work revisits the hypothesis of the so-called ‘lunar terminal cataclysm’ suggested by Tera et al. (1973, 1974) as a strong peak in the meteorite bombardment of the Moon around 3.9 Ga ago. According to the hypothesis, most of the impact craters observed on the lunar highlands formed during this short time period and thus formed the majority of the lunar highland impact breccias and melts. The hypothesis arose from the observation that the ages of highland samples from all the lunar missions are mostly grouped around 3.9–4.0 Ga. Since those missions, however, radiometric dating techniques have progressed and many samples, both old and new, have been re-analyzed. Nevertheless, the debate over whether there was a terminal cataclysm persists. To progress in this problem we summarized results of 269 K–Ar datings (mostly made using the 40Ar–39Ar technique) of highland rocks represented by the Apollo 14, 15, 16, 17 and Luna 20 samples and 94 datings of clasts of the highland rocks from 23 lunar meteorites representing 21 localities on the lunar surface, and considered them jointly with the results of our modelling of the cumulative effect of the impact gardening process on the presence of impact melt of different ages at the near-surface of the Moon.
The considered results of K–Ar dating of the Apollo-Luna samples of lunar highland rocks confirmed a presence of strong peak centered at 3.87 Ga. But since the time when the hypothesis of terminal cataclysm was suggested, it has become clear that this peak could be a result of sampling bias: it is the only prominent feature at the sites with an apparent domination of Imbrium basin ejecta (Apollo 14 and 15) and the age pattern is more complicated for the sites influenced not only by Imbrium ejecta but also that of other basins (Nectaris at the Apollo 16 site and Serenitatis at the Apollo 17 site). Our modelling shows that the cataclysm, if it occurred, should produce a strong peak in the measured age values but we see in the considered histograms and relative probability plots not only the 3.87 Ga peak (due to Imbrium basin), but also several secondary peaks caused by the formation of other basins distributed between 3.87 and 4.25 Ga.
The lunar terminal cataclysm hypothesis is in disagreement with the distribution of K–Ar ages for the highland rocks of the lunar meteorites. The population of lunar meteorites representing localities randomly distributed over the lunar surface, and thus free from the mentioned sampling bias, shows no ∼3.9 Ga peak as it should, if the cataclysm did occur.
We conclude that the statistics of sample ages contradict the terminal cataclysm scenario in the bombardment of the Moon. We also see evidence for the formation of several impact basins between 3.87 and 4.25 Ga which is likewise incompatible with the hypothesis of a short interval cataclysm. There remain other basins, including the largest South Pole – Aitken, the ages of which should be determined in future studies to further clarify the impact history. Sample-return missions targeted to date several key basins need to be planned, and the continued study of lunar meteorites may also bring new details to the general view of the impact bombardment of the Moon.
Juan Luna was a major force of painting tradition in the Philippines particularly in the late 19th Century. Like his colorful paintings, his life was also interestingly complicated which scholars ...and historians were fond of studying about. His paintings are known to be packed with symbolism. In this study, I tried to interpret the painter's works and the intricacies of his life as a nationalist and as a private person. By employing semiotic-hermeneutic interpretation, an exposition of various symbols embedded in his works and what they signify was made. As gleaned in the works interpreted, messages and contents were conveyed and made powerful through his visual metaphors. Apparently, Luna concealed his nationalistic ideas and his innermost feelings in his work.
The formation ages of lunar impact basins are critical to understanding the late accretion history of the inner solar system. Furthermore, the correct interpretation of the provenance and isotopic ...dates of basin-derived impact melt (‘basin melt’) is essential for the calibration of lunar chronology function. However, abundances of basin melt in the lunar near-surface are not well understood. Basin melt has been gardened by a long sequence of subsequent impact events, altering its abundance and size distribution. We developed a numerical model to investigate this process by means of the Monte Carlo method in a spatially resolved model. The fraction of melt in ejecta was tracked globally and at the Apollo 14–17 and Luna 20 sampling sites and was compared with K-Ar age distributions of lunar impact melt breccias. It was found that melt produced by the very large SPA basin as well as the relatively late-forming Imbrium basin should be dominant in the near-surface (top one meter). The simulation shows that the melt component at the Apollo 14–17 and Luna 20 sites is strongly affected by nearby mid- to late-forming basins. Imbrium melt should be abundant in Apollo 14–17 samples; Crisium melt is the most significant component of basin-sourced melt in Luna 20 samples; all the Apollo 14–17 and Luna 20 samples could include melt from Serenitatis and the SPA basin; Nectaris melt should occur in Apollo 16, Apollo 17 and Luna 20 samples; and Orientale melt has no significant mixing in the Apollo 14–17 and Luna 20 sampling sites. In general, besides a prominent age peak at 3.9 Ga (related to the Imbrium basin), the model predicts pronounced abundance peaks of older basin melt (>3.9 Ga) which tend to be absent from distributions of K-Ar ages of impactites from landing sites. The diffusion characteristics of basin melt suggest that for future sampling aimed at collecting early basin melt, the re-excavation zones of late impact craters larger than tens of kilometer in diameter inside basins may provide the highest abundances of melt from early basins.
•Impact gardening of basin melt modeled in 3D to estimate present surface abundance•Estimate relative abundances of differently-aged melt at Apollo/Luna sampling sites•Surface melt abundance strongly affected by nearby late-forming basins•Deficiency of ancient melt compared to aggregated K-Ar sample age distribution
This poem explores the connection between lunar cycles, the feminine consciousness, and ritual practices that articulate the physical experience of being female on earth.
In preparation for the upcoming Luna 27 mission to the south polar region of the Moon, the Package for Resource Observation and in-Situ Prospecting for Exploration Commercial exploitation and ...Transportation (PROSPECT) is undergoing a series of tests to ensure its suitability for polar regolith and volatile analysis. A lunar regolith simulant, NU-LHT-2M, was used for geotechnical validation and volatile extraction testing. Therefore, the physical, chemical/mineralogical, and spectral properties of separate batches of this simulant have been characterised to better understand the results of the instrument laboratory testing phase. Here we compare measurements from two different batches of the simulant to Apollo bulk regolith samples in order to understand the suitability and representativeness of the simulant to the properties of surface highlands regolith. Based on our measurements, we recommend that the physical, mineralogical, and spectral properties of simulants be analysed both before and after space instrument testing campaigns. These bookended measurements would allow for a more detailed understanding of the test phase, including: how the simulants have been altered by the test and, therefore, how the lunar surface may be affected by mission extraction and sampling processes.
The paper presents pioneering data on the comparative study of impact glasses from the Zhamanshin crater and lunar regolith (delivered by the Luna 16, 20, and 24 probes). The data were acquired using ...analytical techniques of ultrahigh spatial resolution. Many of the melt and condensate impact glasses, both terrestrial and lunar, are similar in inner structure and composition, which were controlled primarily by the physics of the impacts and similar compositions of the targets.
The Luna structure of India has been rumored to be an impact crater for more than a decade without any convincing evidence. This structure (1.5–1.8 km) is prominently visible in the low-lying Banni ...Plains of the tectonically active Kutch Basin as a circular morphological feature with a less-prominent rim. Luna area is strewn with melt-like rocks having high specific gravity and displaying wide range of magnetic properties. It contains minerals like wüstite, kirschsteinite, ulvöspinel, hercynite, and fayalite. The whole rock analysis denotes PGE enrichment, with notably higher average concentrations of Ru (19.02 ppb), Rh (5.68 ppb), Pd (8.64 ppb), Os (6.03 ppb), Ir (10.63 ppb) and Pt (18.31 ppb). The target is not exposed at Luna, owing to the overlying thick sequence of Quaternary sediments. The mineralogical and geochemical signatures points to an impact into a target, which is rich in clay with elevated calcium and silica (sand/silt) content. Geochemical data suggests an iron or stony-iron meteorite as the potential projectile at Luna. The silt layer containing plant remnants, underlying the strewn layer, yielded a radiocarbon age of 6905 years, making Luna the biggest crater to result from an iron bolide within the last 10,000 years.
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•Confirmation of Luna as an impact crater uptick the limited numbers of crater in India.•Characteristic mineral of meteorites like wüsite, kirschsteinite, hercynite, and ulvöspinel were identified.•Luna samples have one of the highest Ir values amongst the different terrestrial impactites.•Geochemistry confirms iron bolide as the potential impactor.•An age of <6.9 ka and 1.8 km diameter makes Luna the largest crater within the last 10 ka.
High mountain lakes and their catchments are remote ecosystems in areas with low anthropogenic disturbance. High mountain lakes integrate changes in the atmosphere and catchment areas (e.g., acid ...rain, airborne pollutants, climate change). The present research analyses long-term datasets of meteorological and limnological variables representing two tropical high mountain lakes, El Sol and La Luna, in Central Mexico to identify the impacts of anthropogenic disturbance (i.e., sentinels of global/climate change). The 54-year meteorological analysis showed marked interannual variability with no statistically significant air temperature or rainfall trends. However, from 2000 to 2018, the air temperature increased by 0.5 °C. Accordingly, the lake water temperature increased (Lake El Sol: 0.8 °C, Lake La Luna: 0.6 °C). Although the rainfall displayed no change, the water level decreased in both lakes (1.5 m), most likely associated with increased evapotranspiration. Unexpectedly, the dissolved inorganic nitrogen (DIN) concentration in the lakes decreased. The initial acid pH rose to close neutrality in Lake La Luna and to alkaline values in Lake El Sol. The latter may be a consequence of the lowered SOx and NOx emissions from governmental regulations promulgated to control atmospheric pollution beginning in 2000 and probably resulting in less acidic deposition. An additional explanation for the lakes' deacidification is the increased deposition of alkaline ions derived from activities at the volcano slopes. Since the atmospheric supply is the primary nitrogen source to high mountain lakes, the DIN concentration decline could reflect the reduction in atmospheric HNO3. Thus, Lakes El Sol and La Luna evidenced global change. Both lakes are inside the same crater and are subjected to similar influences; thus, they showed similar responses to global change (increasing lake water temperatures, declining water levels, higher pH value, and lower DIN concentrations). Nevertheless, their differences (e.g., catchment size, surface area, water volume, water depth, trophic status) influenced the magnitude of the impacts, with higher pH increases recorded in Lake El Sol and higher DIN concentrations in Lake La Luna.
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•Air temperature and rainfall were affected by teleconnection indices.•While the air and water temperature increased, the lakes' water levels decreased.•DIN decreased by the reduction of atmospheric acid precursors.•The atmospheric acid precursors reduction increased pH in the lakes.•The global change affected both lakes similarly but with a different magnitude.