... The search for distant objects which can be both galaxies and quasars is one of the most important problems of observational astrphysics, because it allows one to determine cosmological parameters connected with the time of appearence and evolution of stellar systems, large scale structure of the Universe. ... Radio galaxies are important objects to be studied because they are sources of infrared-optical-ultraviolet continuum, emission lines and continual radio emission. ...

... About ATMoB . ... The Observing Committee is starting an Observing Awards Program to promote observing among the membership of the Amateur Telescope Makers of Boston. ... Participant must be a current member of the Amateur Telescope Makers of Boston . ... To qualify for your Observing Award Certificate, turn in your worksheet and drawings to an ATMoB Observing Committee member or observing@atmob.org . ... This Excel sheet has useful macros. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

... Curriculum Vitae Observations and theory of star cluster formation 22) A.K.Dambis and Yu.N.Efremov Journal for History of Astronomy, 31, 115-134, 2000 Dating Ptolemy's star catalogue through proper motions: the Hypparchan epoch 23) B.G.Elmegreen, Yu.N.Efremov, S.Larsen Astrophys. J., 535, 748 - , 2000 A young globular cluster in the galaxy NGC 6946 24) Yu.N.Efremov. ... 28) Yu.N.Efremov. ... The location of star complexes in the Galaxy was studied in papers with E.Alfaro, L.Berdnikov and T.Sitnik. ...

... Next: Cheating Poisson: A Up: Statistical Analysis Previous: Spatial Models and . ... The spatial distribution of stars in the Local Group dwarf irregular galaxy NGC 6822 has been studied, using recent positions and deep photometry for about 15,000 stars in the galaxy. Based on photometrical data, OB stars and red stars could be studied separately. Spatial statistical tools have been applied to the analysis of the spatial structure. ... Figure: Model selection by the aid of CAIC . ...

Next: Transparency of the Stochastic Up: Model of the Galaxy Previous: Frequency distribution of galactic . ... The parameters of the model resulted from a numerical fitting of various data, such as the observed distribution of the young star population and neutral hydrogen, the density of population II stars in the vicinity of the Sun, the galactic rotation curve and the dynamics and distribution of globular clusters   and dwarf irregular satellites of the Galaxy. ...

... Galaxy clusters in presence of dark energy: a kinetic approach . ... The external regions of galaxy clusters may be under strong influence of the dark energy, which was discovered by observations of supernovae Ia at redshift z < 1. The presence of the dark energy in the gravitational equilibrium equation, with the Einstein ? ... diagram where equilibrium solutions are not possible. ... Galactic Cluster in the Presence of Dark Energy . ...

Astronotes Armagh Planetarium's Stellar Blog! ... Comets and Asteroids . ... Image credit:ESO/J.Emerson/VISTA. ... However others are less pessimistic and it has even been claimed that the mysterious ?Wow! signal? received in 1977 originated from the direction M55.б  Sadly, this still unexplained pulse of radio energy originated from a location rather to the northwest of M55 so I doubt if the source was this cluster (if indeed the signal was genuinely of extraterrestrial origin). ... Mysterious Wow! ...

... Session 1 - Stars, star formation, stellar populations and planets . 9.20 10.00 . ... HST Spectroscopy of the Hottest White Dwarfs . ... Coffee break . ... Lunch break . ... A (long) look at neutron stars with HST . ... Session 2 - Nearby galaxies, bulges, spheroids, galaxy formation . ... New HST/ACS Insights into the Evolution of Star-Forming Dwarf Galaxies with Extreme Properties of Cosmological Relevance . ... Deriving properties of Lyman-break galaxies at z~3-5 using HST/VLT/Spitzer data . ...

. Fractal Matter Distribution . Observed fractal galaxy distribution is discuused in: . F.Sylos Labini, M.Montuori L.Pietronero, "Scale invariance of galaxy clustering" astro-ph/9711073 . The home page of "The Debate on fractal Universe"

... All the galaxies are divided into 4 groups depending on the environment type; every subsample contains more than 10 galaxies. ... An effect of environments is seen both for the nuclei and for the bulges: if we consider the clusters (Virgo and Ursa Ma jor) and group centers as dense environments and the field and group periphery as sparse environments, then in the dense environments the stellar populations of S0s are in average older by 4­5 Gyr than in the sparse ones. ...

... О Далекой Галактике . ... Теперь в Далекой Галактике вы всегда можете увидеть свежие фотографии Солнца. ... Форум . Форум "Далекой Галактики" - прекрасное место для общения всех астрономов. ... Новости из космоса . ... Подписаться на новости Далекой Галактики Вы можете здесь: . ... Новости из Далекой Галактики - популярно об Астрономии . ... Если вы хотите выразить свое мнение о сайте "Далекая Галактика", или просто почитать мнения других посетителей - пожалуйста, заходите в Гостевую книгу . ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . Portrait of Sir William Herschel (1738-1822) Royal Astronomical Society . Probably the most famous astronomer of the 18th century, Sir William Herschel discovered, in addition to the planet Uranus, many new nebulae, clusters of stars and binary stars. ... Other Herschel Family Portraits . Mirror by Herschel . Return to A Short History of Armagh Observatory . Last Revised: 2009 November 23rd . ...

... Bad Astronomy . ... Bitesize Astronomy . ... The last step encompassed them all with galaxies , and how we discovered that the Milky Way was not the entire Universe. ... And just like those star clusters, there are different kinds of galaxy clusters. ... There are vast clusters of clusters, called superclusters, which contains hundreds of thousands or even millions of galaxies. ... Our own Galaxy has 400 billion stars in it, yet there are clusters out there with millions of galaxies like our own. ...

... Observations . Objects . ... Canis Major . ... Canis Minor . ... Leo . ... Leo Minor . ... Ursa Major . ... Ursa Minor . ... Herschel 2500 . ... Herschel 400 (I) . ... Globular Clusters . ... AL Globular Club . ... AL Planetary Club . ...

... We address a question if globular clusters (GC) in a protogalaxy could for some time evolve chemically as isolated systems, enriching themselves with heavy elements produced in first supernova events that follow initial star formation. We determine both the critical mass of a protoglobular cluster that is needed to retain the ejecta of the very first supernova, and the critical energy (i.e., number of supernovae) that is needed to expel the residual gas from a cluster of a given mass. ...

Working session on Standard Candles Chair: F. Haberl · Definition of standard candles Sources with constant X-ray flux: white dwarfs isolated neutron stars supernova remnants cluster of galaxies · Scientific drivers for accurate absolute fluxes neutron star radii cosmology (e.g. total mass of galaxy clusters, Sunyaev Zeldovic effect) · Calibration purposes absolute flux ...

... Ciel Espace, le magazine qui vous guide toujours plus loin . ... des pages consacr†йes †а la publication de vos photos Mais c'est aussi une vraie communaut†й avec laquelle partager votre passion et nourrir votre curiosit†й. Accueil Mati†иre noire : une observation d†йfie les astronomes . ... A la une . ... En effet, selon les mod†иles th†йoriques, les concentrations de mati†иre noire sont les lieux o†µ naissent les galaxies. ... Une mati†иre noire au comportement ordinaire ? ... Etat du ciel . ...

. Back to A.Zasov's homepage.

Clusters of galaxies are the largest gravitationally bounded structures in the Universe dominated by dark matter. We review the observational appearance and physical models of plasma structures in clusters of galaxies. ... The knowledge of the complex dynamical and feedback processes is necessary to understand the energy and matter balance as well as to constrain the role of the non-thermal components of clusters. ...

... Structure of Data . ... Catalog . ... In SAI OCL Catalog, we introduce our work on investigation of the Milky Way system of open star clusters. The main goal of our study is a search for new clusters using huge surveys. 168 new clusters have been already discovered by us using J,H,Ks data from 2MASS point source catalog. ... For 141 new clusters, we found their physical parameters using J,H,Ks data from 2MASS catalog and, for a number of clusters, our UBVRI CCD observational magnitudes. ...