Characteristics of small-sized space debris objects using Terskol observatory measurements

The Zeiss-2000 telescope of the International Center for Astronomic and Medico-Ecological Research, National Academy of Sciences of Ukraine (Terskol observatory), with a 2-meter aperture is the largest optical instrument in Europe that is regularly used for investigating space debris in the vicinity of the geostationary orbit. One of the main objectives is to detect and characterize small fragments of space debris that are difficult to approach for other telescopes. During each photometric night, we usually detect four to five unknown fragments of 17th to 20th magnitude. This article provides orbital parameters and physical characteristics of several small-sized fragments of space debris that were detected during observations at Terskol observatory in 2014–2015.     

Ionospheric effects of Poincaré waves in the observations of the total electron content

Disturbances of the daily variations in the total electron content (TEC) of the ionosphere during and after geomagnetic storms, obtained from the observations of the GPS satellite signals, are considered. The specific features of these disturbances consist in the intensification of the variations with periods of 4–6 h, the amplitude of which increase at midlatitudes, and in a weak dependence of local maximums on latitude and their considerable longitudinal variability. The possibility of explaining observed disturbances of the considered daily variations by the generation of standing planetary Poincaré waves is discussed. The estimated periods of Poincaré waves, latitudinal structure of these waves, and their ionospheric effects make it possible to qualitatively explain the observed specific variations in TEC.     

Modeling the Effect of Mesospheric Internal Gravity Waves in the Thermosphere and Ionosphere During the 2009 Sudden Stratospheric Warming

The results of numerical experiments on the modeling of thermospheric and ionospheric disturbances under conditions of sudden stratospheric warming are presented to study the possible mechanisms of such disturbances. Local disturbances caused by a planetary wave with zonal wave number s = 1 and internal gravity waves (IGWs) propagating from the disturbed region in the stratosphere are taken into account as sources of disturbances. It is shown that the inclusion of an additional source of thermospheric disturbances caused by mesospheric variations of atmospheric parameters with IGW periods over the region of sudden stratospheric warming leads to significant changes in the parameters of the thermosphere and ionosphere, including a change in the global structure of the distributions of the gas components of the thermosphere and a shift in maximum concentrations of atomic oxygen to low latitudes of the Southern Hemisphere; there is an increase in the mean values, the diurnal and semidiurnal variations of the ion concentration in the F region of the ionosphere. These features of changes in the parameters of the thermosphere and ionosphere occurred with insignificant disturbances of tidal variations in the thermosphere.     

Tidal and Planetary Waves in the Lower Thermosphere and Ionosphere Simulated with the EAGLE Model for the January 2009 Sudden Stratospheric Warming Conditions

Izvestiya, Atmospheric and Oceanic Physics - The results of analyzing the planetary and tidal variabilities in the mesosphere, thermosphere, and ionosphere acquired in calculations for January 2009...     

Metal contents of recent thermal waters, mineral precipitates and hydrothermal alteration in active geothermal fields, Kamchatka

All the Kamchatkan recent hydrothermal systems are restricted to two volcanic zones, Central Kamchatka of Late Miocene-Pliocene age and East Kamchatka, where several active volcanoes are located. Solutions from active hydrothermal systems commonly contain elements, including As, Sb, Hg, Li, Rb, Cs, B, Cu, Pb, Zn, Ag, Au,Sr and Ba, with the first seven predominating. Higher abundances of ore elements occur in active hydrothermal systems with solutions of sodium chloride composition. Those are the Kireunskaya, Dvukhyurtochnaya and Apapelskaya systems in the Central Kamchatka volcanic zone and the Uzon hydrothermal system in the East Kamchatka volcanic zone. The hydrothermal systems are restricted to structures having very long histories of evolution and which are characterized by contrasting types of magmatism. At present chemical precipitates and altered rocks with higher abundances of As, Sb and trace amounts of Au, Ag, Cu, Ph and Zn are forming in the discharge zones of these hydrothermal systems. Large zones of alterations (alunitic quartzites^* and argillites) with high abundances of As, Sb, Hg, Cu, Pb, Ga and Zr occur in the Central Kamchatka volcanic zone. Here zones of mineralization (cinnabar, realgar, stibnite, orpiment, pyrite, chalcopyrite, sphalerite, galena) occur also; native gold, native silver and gudmundite occur rarely.In the recent Uzon caldera hydrothermal system, As-Sb-Hg mineralization with bitumen and oils is now forming. The ore deposit is zoned, with the most abundant ore minerals being realgar, uzonite, alacranite, stibnite and pyrite. Cinnabar, orpiment, marcasite and native mercury occur occasionally, and single grains of native gold, native silver and native copper are present. At present a total of 7000 t As, 350 t Sb and 200 t Hg have been deposited in the mineralization zone at geochemical boundaries. The general geological and geochemical data suggest that at depth the As-Sb-Hg mineralization may change to gold-silver mineralization.     

High-temporal resolution multimode photospectropolarimeter

A hardware and software complex of the MANIA experiment designed to search for and study the photometric variability of astrophysical objects with a temporal resolution of 10^?6 s is described. The panoramic photospectropolarimeter uses interchangeable optical units, which allow the observations to be performed in four modes—spectroscopic, spectropolarimetric, photometric, and polarimetric. A coordinate—sensitive detector equipped with a set of microchannel plates is capable of recording flux fluctuations from objects and comparison stars simultaneously in different photometric bands and in different polarization planes. The Quantochron 4–48 data acquisition facility operating on line with a computer acquires observational data with a temporal resolution of 1microsecond. The methods of analysis of panoramic data with high temporal resolution are discussed.     

High temporal resolution coordinate-sensitive detector with gallium-arsenide photocathode

We present a coordinate-sensitive detector with a gallium-arsenide photocathode—a vacuum photoelectronic device featuring microchannel gain and a multi-element collector—which had several prototypes manufactured. Quantum efficiency of the photocathode amounts to 48% at maximum, its sensitivity range spans from 350 to 900 nm. The microchannel gain unit consists of two plates with an ion barrier film at the entrance. The coordinates of electron avalanches are determined using a 16-element collector. The spatial resolution, diameter of the working field, and temporal resolution of the detector are equal to 25 μm, 18 mm, and about 1 μs, respectively.     

Extreme carbon monoxide pollution of the atmospheric boundary layer in Moscow region in the summer of 2010

Using data of spectroscopic measurements in Moscow and Moscow region and data of ecological monitoring from Ostankino TV Tower, it has been found that, in the period of intense smoke blanketing of the atmosphere in summer 2010 due to large-scale forest-peat fires on the territory of the European part of the Russian Federation, the carbon monoxide content in the boundary layer and in the atmospheric depth of Moscow region reached the extremely high level of 8 g/m², or 17 ×10¹⁸ mol/cm², and the carbon monoxide concentration in the near-ground atmospheric layer increased to 37.5 mg/m³, i.e., an unprecedentedly large value for Moscow and more than a factor of 7 larger than the one-time maximum permissible concentration for carbon monoxide MPC_ot = 5 mg/m³. In the first decade of August, when intense smoke blanketing of the Moscow region was observed, the average carbon monoxide concentrations varied in the range from approximately 3 to 7 m/g³, i.e., an order of magnitude larger than the annual average concentrations calculated according to data of measurements in 2009. The probabilities of exceeding MPC_ot and multiples of MPC_ot are calculated. Analysis of data of thermal sensing showed that an important feature of the atmospheric boundary layer over the city was a high stability of the lower atmospheric layer with the thickness of 150–200 m, and also long-term nighttime and morning inversions of the air temperature in this layer.     

Large-Scale Haze over Eurasia in July 2016

Doklady Earth Sciences - This paper reports the estimated scales of optically dense haze over Eurasia for the period from July 15 to July 31, 2016, including the Siberian smoky haze (with a smoke...