... 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. ...

PEGASE: Project de'Etude des Galaxies par Synthese Evolutive (by Damien Le Borgne and Brigitte Rocca-Volmerange) . Galaxy colours (by Robin Stevens) . ... Images of radio galaxies and quasars mapped at VLA . Atlas of radio galaxies in 3CRR sample (images, description, classification, etc.) Radio Galaxy and Quasar Images at Other Sites by A.Bridle . ... Radio galaxies in Abell clusters . ... Digitized Sky Survey images . Faint Images of Radio Survey at Twenty-cm at VLA . ...

Next: M.E. Bailey, Director Up: Research Previous: C.S. Jeffery, Research Astronomer Contents . Dr Michael Smith has focused mainly on the earliest stages of stellar evolution: the processes leading to star formation from an initially unstable, collapsing cloud of gas, and the energetic outflows -- jets and winds -- associated with the formation and early evolution of protostars and pre-main-sequence stellar objects. ... Spectacular jets of molecules, however, betray its presence. ...

... SUN MOON MERCURY VENUS MARS, JUPITER SATURN . ... Mars . ... Previously understood that magnetic fields were directly related to rotation, so when I read that Mars, like Venus, didn't have one, my understanding crumbled. What exactly causes magnetic fields in planets? ... RELATED TOPICS: MAGNETIC FIELD . Planetary magnetic fields are definitely related to rotation, but directly not so much. ... Get instant access to subscriber content on Astronomy.com! ...

... Mindful of these biases, I can now explore the relations between the measured rotation periods and various other observables. The hypothesis behind monitoring stellar variability is that active stars have asymmetric spot distributions on their photospheres. ... They found that only stars with rotation periods greater than seven days show variations greater than 0.4 magnitudes at I. Bouvier et al . ... 1993a) demonstrated a relation between X--ray flux and spectral type in ZAMS stars. ...

... We publish 16 Doppler imaging temperature maps for the years 1994-2002 of the active RS CVn star II Peg. ... Through Doppler imaging we want to study the spot evolution of the star and in particular compare this with previous results showing a cyclic spot behaviour and persistent active longitudes. ... The derived temperature maps are quite similar to the ones obtained earlier with a different methods, the main differences occurring in the spot latitudes and relative strength of the spot structures....

... The vertical and slanted dashed lines in the first panel mark the separation distinguishing are as occupied by thick-disk objects according to Hanson et al. (1998) and Martin, Morrison (1998) , respectively. An abrupt change in the dispersion near V res 290 km/s (the vertical dashed lines) is apparent in all panels except the first. discussion in the text | next figure | privious figure . ...

Elliptical galaxies Elliptical galaxies Rough subdivision · Normal ellipticals. ... Dwarf ellipticals (dE's). ... E dE BCD dSph 1013 - 1014 108 - 1013 107 - 109 109 107 - 108 300-1000 1-200 1-10 3 0.1­0.5 100 10­100 1­10 0.1­10 5­100 Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies ...

... Institute for Cosmophysical Research and Aeronomy (IKFIA) (Yakutsk). ... IRE RAN (Moscow). Russian Foundation for Basic Research (Moscow). ... Institute for Remote Environmental Research AEN (Moscow) . ... Russian Federal Research Institute of Fisheries and Oceanography (Moscow) . ... Russian Federal Research Institute of Fishery and Oceanography KamchNIRO. ... Russian Federal Research Institute of Fishery and Oceanography. ... Russian Federal Research Institute of Fishery and Oceanography VNIRO. ...

... Field of research: Extragalactic astronomy. ... NASA Astrophysics Data System (ADS) Abstract Service . ... CADC Home Page . ... CCD Images of Galaxies . ... RUSSIAN LINKS . ... UA Astronomy Personal Home Page - Bill Keel . ... The Shape of the Rotation Curves of Edge-on Galaxies, by A.V.Zasov and A.V.Khoperskov, 2003. ... A Thickness of Stellar Discs, by A.V.Zasov, and D.V.Bizyaev, 2003 . Minimum Velocity Dispersion in Stable Stellar Disks, by A.V.Khoperskov, A.V.Zasov, and N.V.Tyurina, 2003 . ...

New polar ring galaxies catalogue. ... A host galaxy like S0 or E, the polar component is like spirals or irregular galaxies ( gas -rich and bluer) Not only narrow annuli, but also extended disc-like rings Warped and inclined rings Only 20 large-scale polar rings + 6 inner rings were kinematically confirmed from the Whitmore et al. list: - HI maps (Cox et al; Sparke et al. ) - optical-long slit spectroscopy (Reshetnikov et al) - optical ...

... Ultraluminous X-ray sources (ULXs) are located in external galaxies, their X-ray luminosities (10 39 - 10 41 erg/s) are thousand times greater than those of brightest black holes in the Galaxy. ULXs may be supercritical accretion disks around black holes of stellar masses (~10 Solar masses) like that in SS433, or they may be a hypothetical intermediate-mass black holes (hundreds - thousands Solar masses) with standard accretion disks. ... 2) The ULX progenitors were ejected from the star clusters. ...

Astronotes Armagh Planetarium's Stellar Blog! ... 2011 saw 472 Irish primary schools showcase excellence in science and maths. ... The Discover Primary Science and Maths programme recognises the achievements of primary school children and teachers in the application of science and maths.€а Schools registered on the Discover Primary Science and Maths programme can apply for an Award of Science and Maths Excellence after they have met certain criteria for science and maths related activities. ...

... Discovery of 47-s pulsations in the X-ray source 1RXS J225352.8+624354 / arXiv:1305.3439 , May 2013 . ... Optical spectroscopy of X-ray source IGR J22534+6243 / Atel # 4248 . ... Search for counterparts of newly discovered INTEGRAL/IBIS sources / Atel # 4166 . New INTEGRAL Galactic Plane Survey in SkyView / blog . Likely X-ray counterparts of newly discovered INTEGRAL/IBIS sources / Atel # 4165 . AGN in the INTEGRAL/IBIS 9-year Galactic hard X-ray survey / Atel # 4151 . ...

Links on this page are to sites that hold information on the Sun , our nearest star . ... Big Bear Solar Observatory (BBSO) , California, USA. Mauna Loa Solar Observatory (MLSO) , Hawai'i, USA. ... Space Environment Center, Current Solar Images , Boulder, Colorado, USA. ... Solar Data Analysis Center, Latest Images , at GSFC, Maryland. ... NSSDC - National Space Science Data Center, Solar Physics (at GSFC). ... NSSDC - National Space Science Data Center, Space Physics (at GSFC). Back to Links ...

... Arp 81: 100 Million Years Later . ... NASA Explanation: From planet Earth, we view this strongly interacting pair of galaxies , cataloged as Arp 81, as they were only about 100 million years after their mutual closest approach. ... Also known as NGC 6622 (left) and NGC 6621, the galaxies are roughly equal in size but are destined to merge into one large galaxy in the distant future , making repeated approaches until they finally coalesce . ... Publications with keywords: interacting galaxies . ...

... Chilingarian, I., Melchior, A.-L., Zolotukhin, I. 2010: Analytical approximations of K -corrections in optical and near-infrared bands , MNRAS, v. 405, p. 1409 (also arXiv:1002.2360) . ... Calculator . ... calculate spectral energy distributions , K-corrections calculator , UKIDSS YJHK , K-corrections of galaxies , spectral based k-corrections , SDSS filter set K-corrections , K correction code IDL , kcorrect IDL C , . ...

... The concepts of Fourier frequency and wavelet duration are obviously related. ... Among many sensible definitions, we chose to require that the peak of the wavelet mean spectrum should be matched with the singularity of the Fourier transform of the cosine wave. Then, it can be shown that the frequency of the cosine is related to the wavelet duration by the relation . ... The ambiguous definition of the duration of an event is common to the sizing of any object of irregular shape. ...

... F. A. Primini, and H. E. Payne, eds. An Extragalactic Point Source Simulator for SIRTF Pip eline Testing Sonali Kolhatkar, Fan Fang, Mehrdad Moshir SIRTF Science Center, California Institute of Technology, Pasadena, CA 91125 Abstract. ... Our method uses input empirical relations, such as known luminosity functions and galaxy spectral energy distribution templates. ... Point Source Simulator for SIRTF Pipeline Testing 331 -2 log(# galaxies per bin) -4 -6 -8 7 8 9 10 log(L/Lsolar) 11 Figure 2. ...

... Content Model: %Body.Content . ... Note that the ID, LANG and CLASS attributes can be used with virtually all of the elements permitted in the document body. ... CLASS . ... The CLASS attribute is most commonly used to attach a different style to some element, but it is recommended that where practical class names should be picked on the basis of the element's semantics, as this will permit other uses, such as restricting search through documents by matching on element class names. ...