Optical layouts of the WSO-UV spectrographs

Electron acoustic blow up solitary waves and periodic waves are studied in a classical unmagnetized plasma containing cold electron fluid, kappa distributed hot electrons and stationary ions. We obtain Korteweg-de Vries (KdV) equation for electron acoustic waves (EAWs) using the reductive perturbation technique (RPT). Applying bifurcation theory of planar dynamical systems to the obtained KdV equation, we prove the existence of electron acoustic blowup solitary and periodic wave solutions. Depending on different physical parameters, two types of exact explicit solutions of the mentioned waves are derived. Our model may be applied to explain blow up solitary and periodic wave features that may occur in the planetary magnetosphere and the plasma sheet boundary layer.     

1900 Draconid Trail Activity in 2011 and the Prospects for 2014

The article provides an explanation of stronger than expected by the Author Draconids 2011 activity basing on the assumption of unusually high density of 1900 trail of the comet 21P Giacobini-Zinner. Also, a revised prediction for Draconids 2014 is presented, which should also be caused by 1900 trail. For this prediction a “vertical trails” approach is used. This approach is described in the article.     

High‐latitude cold‐based glacial deposits on Mars: Multiple superposed drop moraines in a crater interior at 70°N latitude

Abstract— An impact crater 26.8 km in diameter, located in the northern lowlands (70.32°N, 266.45°E) at the base of the flanking slopes of the shield volcano Alba Patera, is characterized by highly unusual deposits on its southeastern floor and interior walls and on its southeastern rim. These include multiple generations of distinctive arcuate ridges about 115–240 m in width and lobate deposits extending down the crater wall and across the crater floor, forming a broad, claw‐like, ridged deposit around the central peak. Unusual deposits on the eastern and southeastern crater rim include frost, dunes, and a single distal arcuate ridge. Based on their morphology and geometric relationships, and terrestrial analogs from the Mars‐like Antarctic Dry Valleys, the floor ridges are interpreted to represent drop moraines, remnants of the previous accumulation of snow and ice, and formation of cold‐based glaciers on the crater rim. The configuration and superposition of the ridges indicate that the accumulated snow and ice formed glaciers that flowed down into the crater and across the crater floor, stabilized, covering an area of about 150 km² produced multiple individual drop moraines due to fluctuation in the position of the stable glacier front. Superposition of a thin mantle and textures attributed to a recent ice‐age period (?0.5–2 Myr ago) suggest that the glacial deposits date to at least 4–10 Myr before the present. At least five phases of advance and retreat are indicated by the stratigraphic relationships, and these may be related to obliquity excursions. These deposits are in contrast to other ice‐related modification and degradation processes typical of craters in the northern lowlands, and may be related to the distinctive position of this crater in the past atmospheric circulation pattern, leading to sufficient preferential local accumulation of snow and ice to cause glacial flow.     

Comment on: “New” lunar meteorites: Impact melt and regolith breccias and large‐scale heterogeneities of the upper lunar crust,by P. H. Warren,F. Ulff‐Møller,and G. W. Kallemeyn

Abstract We described lunar meteorite Dhofar 026 (Cohen et al. 2004) and interpreted this rock as a strongly shocked granulitic breccia (or fragmental breccia consisting almost entirely of granulitic‐breccia clasts) that was partially melted by post‐shock heating. Warren et al. (2005) objected to many aspects of our interpretation: they were uncertain whether or not the bulk rock had been shocked; they disputed our identification of the precursor as granulitic breccia; and they suggested that mafic, igneous‐textured globules within the breccia, which we proposed were melted by post‐shock heating, are clasts with relict textures. The major evidence for shock of the bulk rock is the fact that the plagioclase in the lithologic domains that make up 80–90% of the rock is devitrified maskelynite. The major evidence for a granulitic‐breccia precursor is the texture of the olivine‐plagioclase domain that constitutes 40—45% of the rock; Warren et al. apparently overlooked or ignored this lithology. Textures of the mafic, igneous‐textured globules, and especially of the vesicles they contain, demonstrate that these bodies were melted and crystallized in situ. Warren et al. suggested that the rock might have originally been a regolith breccia, but the textural homogeneity of the rock and the absence of solar wind—derived noble gases preclude a regolith‐breccia precursor. Warren et al. classified the rock as an impact‐melt breccia, but they did not identify any fraction that was impact melt.     

Losses of birch foliage due to insect herbivory along geographical gradients in Europe: a climate-driven pattern?

The study reports large-scale geographical variation in foliar damage of Betula pubescens and B. pendula by leaf-chewing and leaf-mining insects in Northern and Central Europe. The data were obtained in late summer of 2004 from 90 study sites located along several latitudinal and longitudinal gradients up to 1275 km in length; repeatability of a pattern detected was checked in 2005. Foliar damage in B. pubescens due to endemic herbivory increased in Fennoscandia from 1–2% at 70°N to 5–7% at 60°N; this pattern was best explained by mean July temperatures. Higher foliar losses in southern Fennoscandia were mostly due to an increase in proportion of damaged leaves, while an average consumption per damaged leaf increased only slightly. Foliar damage in B. pendula in Fennoscandia followed the same pattern as described for B. pubescens, although the overall loss of leaf area was only ca. 70% of that in B. pubescens. In contrast, there was no geographical or climatic pattern in damage of B. pendula by insect herbivores in Central Europe; average foliar losses were around 5% between 48°N and 60°N. These data suggest that damage of northern birch forests by leaf-chewing and leaf-mining insects will at least double with expected climatic warming, while in more southern regions the effects of climate change on birch foliar losses due to insect herbivory may be small or even negligible.     

Infrared reflection spectrometry analysis as a non‐destructive method of characterizing minerals and stone materials in geoarchaeological and archaeometric applications

The purpose of this paper is to show the benefits and applications of using mid and far infrared reflection spectrometry (IRS) in the analysis of archaeological materials. Infrared spectral databases do not yet exist for rocks and principal minerals. In support of IRS techniques, a catalogue and new spectral database have been created with over 500 infrared reflection spectra in mid and far ranges from more than 250 different archaeological minerals and stone materials. The reflection spectrum serves as a “fingerprint” of all these materials. This new, non‐destructive method is useful for spectrometric identification and crystal chemical characterization of many rocks and minerals commonly found in archaeological contexts. Three brief examples of IRS analysis of archaeological materials are presented as test cases. It is suggested that IRS could and should become a routine approach in geoarchaeology and archaeometry for identification and provenance studies. © 2009 Wiley Periodicals, Inc.     

The 27-Day and 22-Year Cycles in Solar and Geomagnetic Activity

We study the evolution of the longitudinal asymmetry in solar activity through the wave packet technique applied to the period domain of 25 – 31 days (centered at the 27-day solar rotation period) for the sunspot number and geomagnetic aa index. We observe the occurrence of alternating smaller and larger amplitudes of the 11-year cycle, resulting in a 22-year periodicity in the 27-day signal. The evolution of the 22-year cycle shows a change of regime around the year 1912 when the 22-year period disappears from the sunspot number series and appears in the aa index. Other changes, such as a change in the correlation between solar and geomagnetic activity, took place at the same time. Splitting the 27-day frequency domain of aa index shows an 11-year cycle for higher frequencies and a pure22-year cycle for lower frequencies, which we attribute to higher latitude coronal holes. This evidence is particularly clear after 1940, which is another benchmark in the evolution of the aa index. We discuss briefly the mechanisms that could account for the observed features of the 22-year cycle evolution.     

Preferential low-pH dissolution of pyroxene in plagioclase-pyroxene mixtures: Implications for martian surface materials

Acid weathering of plagioclase-pyroxene mixtures has been investigated with an open system kinetic dissolution model. The modeling reveals that elevated plagioclase/pyroxene ratios observed in some low-albedo martian regions and atmospheric dust could be partially caused by preferential dissolution of pyroxenes at pHs below ∼3-4. Surface materials with smaller grain sizes, affected by lower pH fluids, and/or exposed to longer durations of acid weathering would be enriched in plagioclase. If preferential dissolution is responsible for the observed mineral ratios, the dissolution process likely occurred on a large scale, such as weathering by acid atmospheric precipitates. If dissolution was continuous, modeled timeframes required to produce a high plagioclase/pyroxene ratio are short on geologic timescales; however, it is likely that acid weathering on Mars was episodic, possibly occurring over a longer period of time.