... Actual stars are expected to be more complicated than these simulations. ... The spot may be entirely visible most of the time (one would observe a prolonged flux minimum low), and then part of it may disappear over the horizon briefly and then return (slow rise and then fall back to constant level). ... With the set of observations taken here, I have information available from several comparison stars and color information. ... The period found must be consistent with the data from any given night....

... The FOS employed one of six basic data taking modes to acquire science data: . Spectrophotometry (ACCUM). ... Image. ... ACCUM was by far the most commonly used observing mode. ... In IMAGE mode observations both the number and length of rasters and the y- position of each raster could be specified, so that: 1) a white-light image of all or a portion of the aperture was possible with the MIRROR, and 2) spectra from different portions of the aperture were sampled with a disperser. ...

... The most precisely determined characteristic for accreting neutron stars (NS's) is their period. ... Period changes show fluctuations. ... Some applications of stochastic processes in astrophysics especially in accreting systems were discussed in Lipunov (1987),Hoshino Takeshima (1993) and Lipunov (1992).In Hoshino Takeshima (1993) the authors, using simple models of MHD turbulence, try to explain aperiodic changes in X-ray luminosity of X-ray pulsars. ... Here, -constant angular momentum. ...

... The concept of continuous solar wind developed in 1950's. First, Biermann (1951, 1957) observed comet tails as they passed close to the Sun , and explained the observed tail deflection by a continuous flux of protons from the Sun. Then Parker (1959) showed that the solar corona must expand, and called the outward streaming coronal gas 'solar wind'. ... The expanding solar wind drags also the solar magnetic field outward, forming what is called the interplanetary magnetic field (IMF) . ...

The large magnetic cloud caused by coronal mass ejection at the Sun on January 6, 1997 came to the Earth at early morning on January 10 and continue to interact with Earth's magnetosphere till January 11 (see for example home page of this event prepeared by Dr. M.Peredo http://www-istp.gsfc.nasa.gov/istp/cloud_jan97/event.html ). ... During the days discussed here INTERBALL-1 satellite was in the magnetosphere (MS) near its dusk flunk - see the Fig. 1 for compearing. ...

... The chemically peculiar star HD965 belongs to a rare type of very slow rotators. As far back as in the 90s, G.Mathys (ESO, Chile) supposed its extremely slow rotation as observing split Zeeman components in the spectrum, from which he measured the magnetic field on its surface. Field variation proved to be very slow, and G.Mathys determined that the variability period should be longer than two years. ... Up to now, only two stars with periods longer than 20 years are known. ...

... The Search of a pulsar Once the dedispersed time series is obtained, a Fourier transformation is performed. ... 2 Binary parameters The orbit of a pulsar , as well as any object, in a binary system is determined in its geometrical characteristics, space displacement and syncronised in time by the following parameters : Semimajor axis Eccentricity Longitude of periastron Binary period Time of ascending node a e PB T0 True spin period and observed spin period The ...

... Science . ... Science Users Information > Science Publications > Science Announcements > Phase 2 for ESO Observing Period 96 . ... Observing Facilities . ... Phase 2 Preparation . ... Quality Control and Data Processing . ... ESO HST Image Galleries . ... Starting from the Period 96 Call for Proposals, the seeing requested in the Phase 1 proposal refers to the seeing in the V -band at zenith, while in the Phase 2 material, for most instruments, users should specify the expected Image Quality. ...

Peremennye Zvezdy ( Variable Stars ) 26 , No. ... Moscow 119992, Russia . ... 84/32, Moscow 117997, Russia . ... Our CCD observations compared to times of minima derived from the archival photographic plates and from the NSVS and ASAS-3 data clearly show that the orbital period of the system is variable. ... The phased light curve for the light elements . ... CCD, Moscow . ... and for the current linear light elements (in excellent agreement with the NSVS, ASAS, and our CCD observations): . ...

... The issue is one of remote observing from overseas sites. ... Like a growing number of other overseas-based users, I find it frustrating that I need to travel to Australia to do my observations. ... I realise that one of the issues regarding overseas remote observing is the speed of the network connection. ... Several times I have monitored an observation from Boston, by running every aspect of remote observing remotely except CAOBS. ...

... Fitting the observed dependence includes calculations of the polarization cross-sections averaged over particles orientation and size distribution, their normalization and the comparison of obtained dependencies with Serkowski's curve representing observational data for a chosen star. ... Variations of the polarization factors with wavelength are shown in Fig. 16 for homogeneous spheroidal particles with PF orientation. ... The distinction between prolate and oblate spheroids is also clearly seen. ...

Next: C.S. Jeffery, Research Astronomer Up: Research Previous: J.E. Chambers, Research Astronomer Contents . ... We examine spectral time-series of two lower-chromospheric lines observed with SUMER/SOHO (N I and C II ). ... Two examples of explosive events observed with SUMER/SOHO in transition region spectral lines are reported here; one detected in C IV 1548?, in a region within the northern polar coronal hole, and the other in O VI 1032?, in an active region. ...

... Frequency of wobble same as frequency of forcing mechanism (t) + i 2 (t) · Helmholtz Centre Potsdam ­ GFZ · Consistent estimates of AAM , OAM , HAM computed at GFZ · AAM computed from European Centre for Medium-Range Weather Forecasts · OAM computed from Ocean Model for Circulation and Tides (OMCT) · HAM computed from Land-Surface Discharge Model (LSDM) · Ocean and hydrology Sensitivity to Excitation Model GFZ ECMWF AAM OMCT OAM LSDM HAM 1962­2010 1971­2010 1981­2010 1991­2010 2001­2010! ...

Next: NICMOS/HST H-band (F160W) Images Up: NICMOS Science Previous: HST NICMOS Observations of . ... Observations of P . ... The NICMOS team has devised a comprehensive program of observations of the Galactic Center. ... Data in hand give a first look at variability and a detailed look at the search for the tip of the main sequence will be discussed where NICMOS has demonstrated adequate sensitivity and photometric precision to identify likely O8-B1 stars at the Galactic Center. ...

... 1Fanti+ We presente the result of a seach for new Galactic sources from the BG catalogue. The observations were made with the WSRT at 1.4 GHz, using the short cuts technique. The adopted selection criteria for the observed sample are discussed in detail. ... A catalogue of the sources present in each field was produced; the relevant information about observations and reduction characteristics are given. ... The expected number of Galactic sources present in the observed sample was confirmed. ...

... Up: Data Analysis and Processing Techniques . ... Also, a method for quality control of CCD observations is suggested. ... Everyone who observes a celestial object using a CCD detects moving celestial objects as a ``by product''. ... We hope that our investigations may be useful for near-Earth space control and also for searches of the moving celestial objects through analysis of old and new CCD frames obtained at any amateur or professional astronomical observatory. ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

... the time of observation . ... Observing the Changing Position of the Sun To Establish Cardinal Directions . ... Observations of the Sun's apparent movement across the sky and its pattern of rising and setting in the east and west horizon helped to establish the cardinal directions. ... The final stage of the Sun's return was marked by the observation that the Sun had reached its highest altitude when the full width of your mitted hand could fill the gap between the Sun and the horizon. ...

... There are result from two global VLBI observations at 3.6 cm spaced about 2 years. ... The analysis of the apparent motion, indication of the jet flow trajectory and the other implications for the CSS quasars are discussed. ... The quasar 3C380 ( ; thus 1 arcsec corresponds to 4 kpc for , ) is one of the most powerful radio sources (its radio luminosity at 2.7 GHz is ) ( Wilkinson et al. ... 3C380 is a member of the class of Compact Steep Spectrum (CSS) sources. ...

OBSERVATIONS OF COORBITAL SATELLITES OF SATURN Emel'yanov N., Varfolomeev M. Sternberg State Astronomical Institute, Moscow, e-mail : emelia@sai.msu.ru Institut de MИcanique CИleste et de Calcul des иphИmИrides, Paris, e-mail : emelia@imcce.fr Abstract. To improve the orbital parameters and masses of coorbital satellites of Saturn, Janus and Epimetheus, new observations of these satellites are necessary. ... IN: Saturn. ... New observations of Saturn's coorbital satellites" - Icarus. ...