Abstract: We study the effects of two-dimensional turbulence generated in sunspot umbra due to strong magnetic fields and Alfven oscillations excited in sunspots due to relatively weak magnetic fields on the evolution of sunspots. Two phases of sunspot magnetic field decaying are shown to exist. The initial rapid phase of magnetic field dissipation is due to two-dimensional turbulence. The subsequent slow phase of magnetic field decaying is associated with Alfven oscillations. Our results correspond to observed data that provide evidence for two types of sunspot evolution. The effect of macroscopic diamagnetic expulsion of magnetic field from the convective zone or photosphere toward sunspots is essential in supporting the long-term stability and equilibrium of vertical magnetic flux tubes in sunspots.

Abstract: Long-wave energy emitted by the Earth-atmosphere into space is characterized by changes in power over time that always lag behind the changes in power of the absorbed solar radiation due to slow variation in enthalpy of the Earth-atmosphere system. Long-term variation of the solar energy radiation absorbed by the Earth remains uncompensated by the energy radiated into space over the interval of time that is determined by the thermal inertia. The basic state of the climate system is when the debit and credit sides in the Earth’s global annual mean energy budget (including the air and water envelopes) are almost always unbalanced. The annual mean balance of the heat budget of the Earth-atmosphere over a long time period will reliably define the behavior and magnitude of the energy excess accumulated by the Earth or energy deficit to allow us to determine adequately and to predict beforehand the trend and amplitude of the forthcoming climate change using the prognosis of variations in the total solar irradiance (solar constant). The decrease in solar constant has been observed since the early 1990s. The Earth as a planet will have a negative balance in the energy budget in the future as well, because the Sun is entering the decline phase of the bicentennial luminosity changes. This will lead to a drop in temperature in approximately 2014. The increase in albedo and decrease in greenhouse gas concentration in the atmosphere will result in the additional decrease in absorbed portion of the solar energy and reduced greenhouse effect. The additional drop in temperature exceeding the effect of decreased solar constant can occur as a result of successive feedback effects. A deep bicentennial minimum in solar constant is to be anticipated in 2042 ± 11 and the 19th Little Ice Age (for the last 7500 years) may occur in 2055 ± 11.

Abstract: The mass distribution for the galaxy cluster Abell 2744 (z = 0.308) is investigated on the base of the archival X-ray data of the Chandra observatory. The temperature of the hot gas in the cluster (kT = 9.82 −0.41 +0.43 keV) and the cluster total mass (M 200 = 2.22 −0.12 +0.13 × 1015 M ⊙) for the radius R 200 = 2.38 −0.31 +0.36 Mpc are estimated. The density and mass profiles for the intergalactic gas and dark matter are obtained. The fractions of the intergalactic gas and dark matter in the total mass of the cluster are 15.4 −1.3 +1.3 % and 84.6 −1.3 +1.4 %, respectively.

Abstract: Using high-resolution spectra, we study 31 yellow supergiants of the Large and Small Magellanic Clouds by the method of atmosphere models. Abundance values of 20 chemical elements are determined. It is shown that α-elements are in a slight excess and neutron-capture elements have an excess up to 0.60 dex. Approbation of a new technique for the determination of absolute stellar magnitudes of late-type supergiants is performed. The technique is based on the use of the spectroscopic criterion, namely, depth-line ratios for iron. Absolute stellar magnitudes of nine supergiants of the Large Magellanic Cloud are calculated using this technique. A value of the distance modulus of the Large Magellanic Cloud is estimated: m − M = 18.4 ± 0.3 m .

Abstract: We review published papers dealing with the formation of the silicon solar spectrum and its application for the diagnostics of the solar atmosphere. We pay particular attention to studies on determination of the solar abundance of silicon, its reliable estimation being required for solving the problem of solar metallicity. We analyze the effect of the errors of the oscillator strengths of spectral lines, damping constants, and rates of inelastic collisions with hydrogen atoms on the silicon abundance estimation errors. We also summarize the studies devoted to the investigation of the effect of the deviation from the local thermodynamic equilibrium, inhomogeneous structure of the solar atmosphere, and small-scale magnetic fields on the Si I line formation.

Abstract: The method of determination of heavy element abundances in H II regions (the strong-line method) uses the assumption that some combinations of strong emission line intensities in spectra of H II regions can serve as indicators of metallicities and electron temperatures in nebulosities. Three sets of strong lines are considered, namely, A (R 3, R 2, N 2, S 2 lines), B (R 3, R 2, N 2 lines), and C (R 3, N 2, S 2 lines). Strong line intensities are normalized to the H β intensity). We searched for an unambiguous relationship between strong emission line intensities of these line sets in spectra of H II regions and their compositions. The extensive model grid for H II regions is computed. Chemical compositions of nebulosities and intensities of A and C lines are shown to be related unambiguously. For the B line set, 5% of model H II regions do not have any unambiguous relationship, namely, the models with appreciably different oxygen and nitrogen abundances in H II regions can have similar intensities of the B set lines. The versions of strong-line method (calibrations) using the A and C lines are more reliable than those based on the B lines.

Abstract: The propagation of ultra high energy cosmic rays in Galactic and extragalactic magnetic fields is investigated in the present paper. The motion of charged particles of different energies and chemical composition is simulated using different Galactic magnetic field models. Positions for the real sources of events registered at the Auger observatory are calculated taking into account the influence of both Galactic and extragalactic turbulent fields. The possibility of their correlation with the Centaurus A radio galaxy is analyzed.

Abstract: We studied the dependence of the Ap-index describing the geomagnetic disturbance on the Moon’s phase. We processed available data for cycles 20–23 of the solar activity by the epoch super-position method. We discovered that, in the declining branch of the solar cycle, the highest values of the Ap-index relative to an average value are observed near new moon. The difference of the Ap-index values for new moon and full moon is approximately 18%. In the branch of increase and maximum of the solar cycle, we observed minimum values of the Ap-index during several days before full moon, and maximum values of the Ap-index take place during several days after full moon. The conclusion follows from this that the mechanism of the Moon’s effect on the earth’s magnetosphere is different essentially for intervals near new moon and full moon.

Abstract: Observations of the Fe I line are used to simulate spatial and temporal pressure variations in the solar photosphere. The local internal gravity waves, which are essentially structures that are quasi-periodic in space (on granular and mesogranular scales) and time and propagate along inclined paths at subsonic velocities, are isolated by appropriate filtering. The phase and group velocities of the wave trains are orthogonal; their z-projections are of the opposite sign.

Abstract: We compiled a catalog (containing astrometric and astrophysical characteristics) of 4 302 200 stars with high proper motions (no less than 40 mas/year) using original measurements of proper motions of stars from the catalogs FONAK 11, HIPPARCOS, “Tycho-2,” UCAC2,3, CMC (STAR 11), PPM, PPMX, NPM1, NPM2, XZ80Q, Pul-3, Pul2, NLTT, GCVS, LHS, “Lowell Proper Motion,” and “Bruce Proper Motion,” as well as some data from approximately 800 other published sources The location of our catalog is ftp://ftpmaokievua/pub/astro/h-pms3dat

Abstract: We investigate whether it is possible to overcome the limitations on the efficient application of Fourier-component phase accumulation method. We suggest the use of an instrument with a composite aperture for observation. It is shown that, in this case, the limitations are shifted as many times as the subaperture’s size is less than the typical size of atmospheric inhomogeneities. The interferograms obtained by means of a multibeam interpherometer are processed with the help of the total phase accumulation method using a computer model and the results are presented in the paper.

Abstract: The phenomenon of magnetic field generation in an astrophysical plasma in the frame of developed magnetohydrodynamic (MHD) turbulence is considered. The functional quantum field renormalization group approach is applied to helical anisotropic MHD developed turbulence which is stabilized by the self-generated homogeneous magnetic field. The purpose of the study is to calculate the value as well as direction of the magnetic field in the stochastic dynamo model. The generated magnetic field is determined by ignoring divergent rotor part of Green function of the magnetic field. It is shown that the magnetic field direction is connected with unique existing vector n describing the anisotropic turbulence forcing.

Abstract: We determine LTE abundance of silicon from 65 lines of Si I using one-dimensional semiempirical models of the solar atmosphere HOLMUL, MACKKL, and VAL,C. Our list of lines is considerably larger than lists used earlier. We confirm the reliability of the oscillator strength scale of E.A. Gurtovenko and R.I. Kostik for Si I lines that was based on the fitting to the observed solar equivalent widths. It is shown that this scale is displaced by +0.073 dex and −0.026 dex from experimental scales derived by Becker et al. and Garz, respectively. The difference between “solar” and experimental oscillator strength scales hardly depends on their lower excitation potentials, wavelengths, and equivalent widths. This difference can be interpreted as a total error caused by the choice of the one-dimensional model of atmosphere, the neglect of NLTE effects, the ignoring of the granulation, errors of the van der Waals damping constant, the microturbulence velocity, and the observed equivalent width. We study the effect of changes in various input parameters on the obtained LTE abundance of silicon and show that both the experimental scale of Becker et al. and the displaced “solar” scale produce almost the same silicon abundance. A total root-mean-square error of the abundance, which is caused by errors in equivalent widths and the microturbulence velocity, is 0.02 dex. The use of the semiclassical theory of Anstee, Barklem, and O’Mara for the description of the van der Waals damping constant leads to the emergence of a correlation of the abundance obtained from Si I lines with the equivalent width. There is no such correlation when using the classical Unsold approximation with an enhancement factor E = 1.5. On average, differences in abundances obtained using the mentioned approximations do not exceed 0.03 dex. At E = 1.5, the LTE silicon abundance calculated using the HOLMUL model with “solar” oscillator strengths referred to the experimental scale of Becker et al. is equal to 7.594 ± 0.015, whereas the LTE silicon abundance calculated using the VAL,C model is 7.623 ± 0.021.

Abstract: Using the data of observations in the Fe I line, the spatial-time variations of pressure in solar photosphere are reproduced, and local internal gravity waves are identified through the filtration. Based on the power spectra of gravity waves, some integral features of excitation and propagation of g-modes in real solar photosphere are studied which are excited by the dynamical processes near the boundary region of penetrative convection.

Abstract: Spectral types (M4–M6), effective temperatures Tef (2700–2900 K), and free fall accelerations logg (4.0–4.5) are determined for five M dwarfs using their energy distributions in the spectral range λλ = 680…840 nm. Stellar spectra with resolutions R = 4000 were obtained using the IMACS spectrograph mounted on the ESO Walter Baade 6.5-m telescope. The spectral types are derived from spectral indices and the effective temperatures of the stars are estimated based on their spectral types. Values of Tef and logg are also derived from the comparison between the observed and theoretical energy distributions, calculated both for dust-free, standard NextGen model atmospheres of red dwarfs, and for semiempirical models considering the presence of dust in stellar atmospheres according to the technique developed by Pavlenko et al. We determine dust parameters for stellar atmospheres of these stars, and establish that it is necessary to account for the decrease in concentration of TiO molecules due to their condensation on dust grains, when Tef < 3000 K. We conclude that the radiation scattering by dust grains does not have an appreciable effect on energy distributions in the spectra of the considered stars.

Abstract: An attempt is made to determine the spatial location of the main source of short-period comet nuclei. Numerical calculations for the orbital evolution of Jupiter family comets, medium-period comets, and Centaurs are used to show that the orbits of small solar system bodies tend to evolve in the direction of increasing semimajor axes. This relates to bodies that can experience encounters with planets and whose orbital evolution is shaped by gravitational perturbations. It is concluded that there is good reason to search for the main source of the nuclei of Jupiter family comets at distances of 6 AU or less from the sun.

Abstract: Emission lines have been found in the spectra of seven objects that coincide with the X-ray sources in the spiral galaxy M 101 within 10 arsec box. Five objects are H II regions, one is a star-like source near the galactic center, and another is a distant galaxy projected on the disk of M 101. Three H II regions have a narrow emission line Hα in their spectra, while the spectra of two other H II regions contain a wide emission component that contribute approximately 12% and 2%, respectively, to the Hα flux. The forbidden lines [O III] λ 500.7 nm and [S II] λ 671.7 + λ 673.1 nm in the spectra of all these H II regions have no wide components in their profiles. This suggests that the X-ray sources inside or near the H II regions have only a weak effect (if any) on the optical emission spectra of those H II regions.

Abstract: I provide evidence for the importance of the Jeffreys law of error in the analysis of O-C residuals. This law is used to show that, under uniform metrological conditions, an experiment is considered to be performed correctly only if the O-C values have a t-distribution with five to nine degrees of freedom (ν) or Jeffreys’s form of the Pearson type VII distribution with the exponent m of three to five. Under nonuniform conditions, the left boundary for ν can move to the left but cannot be less than three, and the left boundary for m can also move to the left but cannot be less than two.

Abstract: We discuss possible mechanisms for the formation of albedo spots on asteroids. We infer that the most likely mechanisms are impact cratering and related processes. This is confirmed by the reflectance spectra of the asteroids 10 Hygiea, 135 Hertha, and 196 Philomela, the results of a spectral frequency analysis of the sizes of features on the surface of 4 Vesta and 21 Lutetia, and the estimates for the parameters of impact features.

Abstract: Values of the Nikol’skii geometric flattening index of the solar corona, H, have been collected for 77 total solar eclipses from 1860 to 2010. The dependence of the H index on the Wolf number and the phase of solar activity is studied. The H index is found to take values in the range 0.9 to 2.5 and to anticorrelate with solar activity: the maximum values of the index are observed at solar minima and the minimum values are observed at solar maxima. In addition, the correlations between the H index and the Ludendorff photometric flattening index a + b and between the H index and extent of polar ray systems along the limb are investigated.

Abstract: Data of GPS-satellite observations from permanent stations located in Ukraine (Main Astronomical Observatory of the National Academy of Sciences) and in Eastern Europe were reprocessed using the Bernese GPS software ver. 5.0. The impact of the models of relative and absolute variations of the phase centers corresponding to the different antenna/radome combinations was examined in determining coordinates of the permanent GPS stations.

Abstract: Abundances of europium for 112 FGK dwarf stars of thick and thin disks have been determined in the metallicity range of −1.0 −0.2 dex they are, probably, different.

Abstract: We performed a series of CCD observations in BVRI bands of a celestial region in cluster M67 (NGC 2682) to study the photometric system of the Kyiv network telescope. The signal recording system consists of a CGE-1400 telescope, Celestron #94175 focal reducer, an automatic turret with a set of UBVRI filters, and a Rolera Mgi CCD camera. The operating field of the system is 10.62′ × 10.62′. CCD images are processed in the MIDAS/ROMAFOT package. The reduction coefficients of the instrumental photometric system relative to Johnson’s BVRI system are determined. The resulted value of the module of distance to cluster M67 V − MV = 9.63m does not contradict the results of other researchers. The mean square errors for one determination of stellar magnitude for different bands are 0.02–0.12m. The errors in determining equatorial coordinates in the TYCHO-2 catalog system are ± 1″.

Abstract: Statistical properties of solar granulation in an active region on the solar surface from the photosphere to the lower chromosphere are studied. We use the values of the velocity, intensity, and magnetic field that were obtained at different heights in the solar atmosphere according to the observation data on the VTT telescope at Observatorio del Teide, Tenerife. The changes in the line’s parameters (central depth of the line, halfwidth, equivalent width, and central depth shift) and convective velocity are presented as functions of the value of the magnetic field. We propose a 16-column model of solar granulation depending on the direction of motion of convective elements and on the sign of contrast at two heights—in the continuous spectrum and in the highest layer (h = 650 km). We found that the magnetic field impedes the change in the sign and motion direction of convective elements.

Abstract: We determined brightness distribution in the plasma tail of comet C/2009 R1 (McNaught) using observations with a small Newtonian reflector (200/1000) on June 9–12, 2010. Images of the comet were detected using short exposures with a Canon CMOS APS-C camera. The brightness distribution is simulated and the parameters of the cometary plasma tail are obtained within the diffusion model. The magnetic field induction in the cometary tail, lifetime of light particles, and the lengthwise and transverse ion diffusion coefficients are estimated.

Abstract: The longitudinal magnetic field measured using the Fe I λ 525 and Fe I λ 524.7 nm lines and global magnetic field of the sun differ depending on the observatory. To study the cause of these discrepancies, we calculate the H ‖(525)/H ‖(524.7) ratios for various combinations of magnetic elements and compare them with the corresponding observed values. We use the standard quiet model of the solar photosphere suggesting that there are magnetic fields of different polarities in the range between zero and several kilogauss. The magnetic element distribution is found as a function of magnetic field strength and the parameters of this distribution are determined for which the calculated H ‖(525)/H ‖(524.7) ratio agrees with the observed one. The sigma-components are found to be shifted differently for various points of the Fe I λ 525 nm profile calculated for the inhomogeneous magnetic field. The farther the point is from the line center, the larger the sigma-components shift. Such a peculiarity of the profiles may be responsible for the discrepancies in the measured values of the global magnetic field obtained at different observatories. The increase in modulus of the global magnetic field during the maxima of solar activity can be due to a larger fraction of magnetic elements with kilogauss magnetic fields.

Abstract: We studied variations in the structure of plasma and dust tails of the C/2006 M4 (SWAN) comet during a long observation period (September–December 2006). We found sizes of grains ejected by the comet from the synchronic-syndynamic analysis of comet images. We calculated solar wind speed for high heliographic latitudes from calculations of the aberration angle of the comet plasma tail. Rapid changes in the calculated values of the solar wind speed are caused by its variable transversal component.

Abstract: A spectrum of a sunspot in the range of the Li I λ 670.8 nm line and some lines of Ca I, Ti I, Al I, and Na I was measured. Observations were carried out with the TST-2 telescope of the Crimean astrophysical observatory on August 21, 1981. A model of the spot was calculated from the observed profiles of the Ca I, Ti I, Al I, and Na I lines. From the calculated model and the observed profile of the Li I λ 670.8 nm line, the lithium abundance was estimated as log(NLi) = 0.78 (in the scale of logA(H)= 12.0).

Abstract: New expressions for ON and NS calibrations (we call them ON11 and NS11 calibrations) for the determination of oxygen and nitrogen abundances in HII regions are proposed. New criteria for the division of HII regions into three classes (hot, warm, and cold) are also proposed. ON11 and NS11 calibrations provide more accurate determination of oxygen and nitrogen abundances from integrated emission spectra, in comparison with ON and NS calibrations. Oxygen and nitrogen abundances are estimated for a sample of 57 470 SDSS galaxies using ON11 and NS11 calibrations. Strongline flux measurements for SDSS spectra of these galaxies are taken from the MPA/JHU catalog. A “mass-metallicity” diagram for several redshift ranges is constructed. It is found that the interstellar medium of galaxies with high masses log(M/M ⊙) > 11.3 was hardly enriched with either oxygen or nitrogen over the last 4 Gyrs (corresponding to the redshift interval z = 0–0.4). This indicates that an active stage of star formation in massive galaxies was completed more than 4 Gyrs ago. For galaxies of lower masses, changes in oxygen and nitrogen abundances over the time period under consideration increase as galaxy mass decreases.