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. ...

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The first indication that the sun might be emitting a "wind" came from comet tails , observed to point away from the Sun, whether the comet was approaching the Sun or whether it was moving away. ... Comet Halley, with plasma tail kink . ... Sunlight pressure cannot explain such behavior, but in 1943 Cuno Hoffmeister in Germany, and later Ludwig Biermann, proposed that apart from sunlight, the Sun also emitted a steady stream of particles, a "solar corpuscular radiation" which pushed the ions. ...

The 2dF QSO Redshift Survey (2QZ) . ... Before jumping into all the finer details of teh survey, a brief non-astronomer's guide to redshift surveys is available. ... The primary scientific aims of the QSO survey are: (1) to obtain the primordial fluctuation power spectrum out to COBE scales, (2) to determine the rate of QSO clustering evolution in the non-linear and linear regimes and hence obtain new limits on the value of and the bias parameter, (3) to apply a powerful geometric method to measure . ...

The structure of gas lagers in the spiral arms of Galaxy . ... The large-scale layer structure of the gas spiral arms of Galaxy (figures 1 and 2) was found out for the first time in the galactic longitudes 10 - 40 degrees, of distances of 6 kpc from the centre of Galaxy right up to its external part. 3-4 large-scale layers of thickness 600 - 800 pc is usuall observed in the arms across the plane of Galaxy. ... Figure 1. ... The location of layers HI of the external spiral arm. ...

Short-Period Comets: Origin and Terrestrial Impact Hazard . ... The model is consistent with the basic observed distributions of near-parabolic comets, short-period comets, Centaurs and high-eccentricity trans-Neptunian objects.This model requires that initial objects in the early Solar System are concentrated to the outer planetary region, and the physical lifetime of comets in the inner planetary region at the present epoch is an increasing function of initial perihelion distances. ...

. F IGURE . 1. The distribution of F stars in our sample from the observed distances from the Sun. Solid curve gives a power-law approximation of the number of stars as a function of the distance within R obs =50 pc and the dashed line is its extrapolation up to 60 pc. The arrow indicates the upper boundary of the domain where the sample is complete. discussion in the text | next figure .

... We present the algorithm and implementation details for the robust, realtime bandpass removal and calibration routine developed for the HI Parkes All Sky Survey project. ... Traditionally, the bandpass that is present in single-dish 21 cm spectra is removed by observing in a ``signal-reference'' mode. ... The robust bandpass removal algorithm implemented for the HIPASS Project successfully produces calibrated HI emission line spectra for most of the survey data. ...

... Observing . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... Reproducing the large-scale universe . ... Now, an international team of astronomers has reproduced the observed galaxy clustering by generating thousands of simulated galaxy catalogs. ... An international team of astronomers has now reproduced the observed galaxy clustering and determined the uncertainties in the measurement of observed quantities by generating thousands of simulated galaxy catalogs....

... Galaxies rotate and move in clusters as if a tremendous amount of unseen matter is present. But does dark matter exist in the greater universe too -- and if so, where? ... In the above frame from a computer simulation of our universe , a 300 million light-year slice shows dark matter in gray and galaxies as colored circles. ... Publications with keywords: universe - dark matter - 2dF survey - simulation . Publications with words: universe - dark matter - 2dF survey - simulation . ...

... Exposure Time Calculator (ETC) . Survey processing . ... VISTA is a 4-m class wide field survey telescope for the southern hemisphere, equipped with a near infrared camera (1.65 degree diameter field of view at VISTA's nominal pixel size) containing 67 million pixels of mean size 0.34 arcsec and available broad band filters at Z,Y,J,H,K s and a narrow band filter at 1.18 micron. A wide field visible camera, if constructed, could also be used on VISTA. ... Tile . ... ESO VISTA Public Surveys . ...

... The Sun . ... The Corona . ... Solar Wind . 18H.Solar Wind obs. ... Field . ... The first indication that the sun might be emitting a "wind" came from comet tails , observed to point away from the Sun, whether the comet was approaching the Sun or whether it was moving away. ... The corona, like the Earth's atmosphere, is held down by the Sun's gravity. ... The particles at its "roots" stay with the Sun, but those in the high corona flow out with the solar wind, to the Earth's orbit and far beyond. ...

The ESA/ESO Astronomy Exercise Series 2 . The Distance to Messier 100 as Determined by Cepheid Variable Stars . ... The small variations in distance to the individual Cepheid variable stars in the Cloud are negligible compared with the much larger distance to the SMC. ... In this way Cepheid variable stars can be used as one of the 'standard candles' in the Universe that act either as distance indicators themselves or can be used to calibrate (or set the zero point for) other distance indicators. ...

FEATURES OF THE HYDROGEN DISTRIBUTION AROUND LUNAR CRATERS PROCLUS AND KEPLER. ... In result of analysis of the data Lawrence and Feldman constructed the hydrogen distribution on the lunar surface [1]. ... However, the authors shown, that EN flux data features may be explained by other element abundance in the lunar soils, namely: Si, Ca, Gadolinium (Gd), Samarium (Sm) and Fe. ... Using of the Feldman's interpretation of the Lunar Prospector data [8], we constructed hydrogen distribution map (Fig.1). ...

... The Radon transform (also known as the Hough transform) is formulated as a family of line integrals through a two-dimensional function. ... The Radon transform provides us with a simple means of computing the FF plane of the autochirplet transform, by using the Wigner distribution, and arriving at a transform space that tells us basically the same information as the chirplet FF-plane, except that we benefit from the greater resolution of the Wigner distribution. ...

Today's APOD | ... Galaxies rotate and move in clusters as if a tremendous amount of unseen matter is present. ... Specifically, present analyses of above WMAP all-sky image indicate that the universe is 13.7 billion years old (accurate to 1 percent), composed of 73 percent dark energy , 23 percent cold dark matter , and only 4 percent atoms , is currently expanding at the rate of 71 km/sec/ Mpc (accurate to 5 percent), underwent episodes of rapid expansion called inflation , and will expand forever . ...

... Pulsars offer a variety of observables for study of interstellar scattering. Observations of scattering of nearby pulsars and intra-day variable quasars point to the existence of a component of the interstellar medium (ISM) which has properties quite different from the more distant, diffuse ISM. ... The time series of electric field emitted by the pulsar is convolved with an impulse-response function due to scattering, when sampled at the observer plane [1]. ... Nearby interstellar scattering. ...

ASTRONOMICHESKII TSIRKULYAR No.1573, 2010 April 12 1995 2009 . A Comparison of the Latitudinal Variations of the Methane Absorption Bands on Saturn's Disk at Equinoxes 1995 and 2009 Abstract. The observations of Saturn at last equinox 2009 have detected significant differences of the latitudinal variations of the methane absorption from observed at 1995 equinox . ... 1995 . 2008- 2009 , ­ . ... 4 ( 580-880 ) , (.1) , 2008-2009 . ... 2 , 4 725 1995 2009 . ... 1995 2009 15 , 1980 1995 . ...

To appear in "Fourth Workshop on Robotic Autonomous Observatories (2015)"RevMexAA(SC) METEOR OBSERVATIONS WITH MINI-MEGATORTORA WIDE-FIELD MONITORING SYSTEM S. Karpov, 1, 3 N. Orekhova2 G. Beskin, 1, 3 A. Biryukov3,4 S. Bondar,2 E. Ivanov,2 E. Katkova,2 A. Perkov, and V. Sasyuk3 RESUMEN 2 Favor de prop orcionar un resumen en espanol. ... The faintest detected meteors has the peak brightness about 10 mag, while the ma jority - from 4 to 8 mag. ... 2010; Karpov et al. 2013; Beskin et al. ...

Variations of total ozone content and lower ozone stratosphere temperature in Antarctic Region during winter-spring period A.V. Grytsai National Taras Shevchenko University of Kyiv Astronomy and Space Physics Department assen@univ.kiev.ua Data, used in the work work Total ozone: Total Ozone Mapping Spectrometer (TOMS) measurements during 1979 - 2005 and Ozone Monitoring Instrument (OMI) ones for 2006, for http://toms.gsfc.nasa.gov/ftpdata.html. ... A long-term TOC decrease is significant. ...