... RATAN-600 data for the BL Lacertae objects (multi-frequency catalogue, Version 1.0) . GPS radio sources . ... BL Lacertae objects . ... The difference between these objects is the peak frequency of the synchrotron component of their spectral energy distribution (HBLs: high-energy peak, LBLs: low-energy peak, IBLs: intermediate). ... The observations were carried out with the RATAN-600 radio telescope during 2006-2011 at six frequencies: 1.1, 2.3, 4.8, 7.7, 11.2 and 21.7 GHz. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Risks Comparable to NEOs . ... The Increasing Rate of Discovery of Asteroids . ... Comet and Asteroid Collision Probabilities . ... Extreme albedo comets and the impact hazard (PDF Format) . ... Asteroid Impact Animations . ... Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids - 2002 . ... The Spaceguard Survey Report, 1992 (PDF) . Tsunami from Asteroid/Comet Impacts . ...

... A radio galaxy is a galaxy that emits an unusually big amount of energy at radio wavelengths. ... Inside of each galaxy with an active nucleus (radio galaxies are among them) there must be a system of a "central machine" responsible for the colossal amount of the emitted energy from radio to gamma ranges. ... Sometimes a radio source in an active galaxy may flare again if the needed conditions appear (a new portion of matter would fall into the furnace of the "central machine"). ...

As a service to the astronomical community, we are recalibrating all archival Hubble Space Telescope Faint Object Spectrograph UV and optical spectrophotometry of active galaxies and quasars in order to extract uniformly calibrated spectrophotometric data for further detailed scientific investigations. ... NGC 4151 CLOUD F . NGC 5548 . ... NGC 4395 . ... NGC 4486 . ... NGC 4486 JET KNOT-A . ... NGC 4486 CLOUD-A . ... NGC 3031 . ... NGC 1068 . ... NGC 1068 CLOUD A . ... 1413+117A . ... NGC 4151 . ...

... A universal physical relation for quasars . ... Harvey Tananbaum and his collaborators have first observed a relation between the soft X-ray and the optical/ultraviolet emission in AGN in 1979. Such relation is nonlinear, and it is usually parameterized as dependence between the logarithm of the monochromatic luminosities at 2500 †Е ( L 2500†Е ) and 2 keV ( L 2keV ) . ... Yet, the dispersion along the L 2500†Е тАУ L 2keV relationship is found to be rather high, typically ~0.35тАУ0.4 in log units. ...

We present UV and optical spectropolarimetry of two highly polarized IRAS-selected quasi-stellar objects (QSOs), IRAS 13349+2438 and the broad absorption line QSO (BALQSO) IRAS 14026+4341. ... We construct full radiative transfer models of these systems consisting of a dusty sphere of modest optical depth illuminated axisymmetrically from within by a power-law QSO spectrum. We show that this simple model successfully reproduces the qualitative polarization properties of the objects. ...

... ESO, the European Southern Observatory . ... ESO's Governing Bodies . ... Travel to ESO Headquarters . ... Visits to ESO Sites . ... Architecture at ESO . Collaborations with ESO . ESO Acronyms . ... Green ESO . ... ESO . ... Active Optics . ... Integral Field Units . ... Caf†й Kosmos in Munich . ... For more information about this event, visit: http://www.eso.org/public/events/special-evt/cafe-and-kosmos.html . ... Caf†й & Kosmos . ... Related announcements: . ... Caf†й Kosmos , Poster . ...

... The Cloudy Cores of Active Galaxies . ... Credit Copyright: NASA's GSFC , W. Steffen ( UNAM ) Explanation: What would it look like to travel to the center of an active galaxy? Most galactic centers are thought to house black hole s millions of times more massive than our Sun. ... Publications with keywords: Galactic Center . Publications with words: Galactic Center . ... The Galactic Center in Infrared . The Galactic Center Across the Infrared . The Galactic Core in Infrared . ...

USING THE CORRELATION BETWEEN ISGRI SURVEY RESULTS AND OTHER CATALOGUES TO AID SOURCE IDENTIFICATION John B. Stephen, A. Malizia and L. Bassani IASF-INAF, Via P. Gobetti 101, 40129 Bologna, ITALY, E-mail: stephen@iasfbo.inaf.it ABSTRACT In order to help in the identification of INTEGRAL/ISGRI sources, we have developed a software package which allows a rapid and detailed cross-correlation to be performed between various source catalogues. ... We show below some preliminary results from this analysis. ...

Unlike at lower redshift, where there is a 40% detection rate, surveys for 21-cm absorption arising within the hosts of z 1 radio galaxies and quasars have been remarkably unsuccessful. ... In order to find this "missing" gas at high redshift, we have therefore undertaken a survey of z 2 radio sources, selected by optical faintness. ... The possibility that the other five could be located at lower photon rates cannot be ruled out, although zero detections out of five is not statistically significant. ...

... 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. ...