The Mass-Density of the Universe and the Distribution of Dark Matter Neta A. Bahcall Princeton University, USA One of the most fundamental questions of cosmology is: How much matter is there in the Universe and how is it distributed? Here we show that several independent measures - including those utilizing clusters of galaxies - all indicate that the mass-density of the Universe is low: only 20-30% of the critical density. ... The results reveal a low den- sity of 0.16+-0.05. ...

TALKS ST EL L E Raffaele Gratton INAF - Osservatorio Astronomico di Padova Stellar abundances and the chemical evolution of stellar systems: the Italian contribution The chemical composition of stellar syst the last few years, exciting results have and efficient spectrographs. ... Once the observations of all clusters will be completed for at least one season, we plan to better describe and model the evolution of the stellar angular momentum from the PMS to the TAMS. ...

... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... SUBJECT: 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... which will be held in Beijing, P.R. China, from August 25-29, 2014, hosted by Chinese Academy of Sciences . ... China), . ... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. ...

... S.P. KOROLEV ROCKET AND SPACE CORPORATION ENERGIA . ... OAO RSC "Energia" . ... Flights Chronology . ... Acquiring new scientific information about the role of the right and the left heart in adaptation of the blood circulation system to long-term space flight conditions. ... Investigation of relations between hemodynamic and energetic characteristics of the heart in different phases of a long-term space flight. ... Data carrier "Cardiovector - Data". ... 2015 JSC "S.P. Korolev RSC "Energia" . ...

... Models of central engines (1) Potential of disk accretion onto stellar mass black holes: disk binding energy: thin disk life time: - accreted mass - disk outer radius - gravitational radius - Shakura­Sunyaev parameter Ultra-dense Hyper-Eddington neutrino cooled disks !! ... 1989); Neutron star + Neutron star Neutron star + Black hole White dwarf + Black hole Black hole + compact disk Burst duration: 0.1s ­ 1.0s Released binding energy: (1.2) Collapsars­ origin of long duration GRBs? ...

... We report on the preliminary results of experiments using a Bayesian cluster method to cluster objects present in photographic images of the POSS-II. ... We believe that the application of such algorithms to large-scale astronomical sky surveys can aid in cataloging the detected objects, and may even have the potential to discover new categories of objects. ... We have thus started to explore new clustering analysis and unsupervised classification techniques for this task. ...

ALMA discovers an unexpected population of compact interstellar clouds inside the dwarf irregular galaxy WLM. These star-forming clouds provide the necessary nurturing environment to form star clusters. As seen in relation to an optical image of the galaxy taken with the Blanco 4-meter telescope, (box upper left) an overlaying blanket of hydrogen gas (red) imaged with NRAO's VLA telescope provides the pressure necessary to concentrate molecules of carbon monoxide (yellow) as seen with ALMA. ...

... I.A.Dynnikov, Three-page approach to knot theory. ... Universal semigroup, Funktsional'nyi Analiz I Prilozhenija, 34 (2000), no.1, 29-40 (Russian); English translation in Functional Analysis and Its Appl. 34 (2000), no.1, 24-32. I.A.Dynnikov, Finitely presented groups and semigroups in knot theory. ... Math. 2000, no. ... English translation: Russian Math. ... A.Vershik, Numerical invariants of exponential groups, and a locally free approximation of braid groups (in Russian), Zapiski Nauchn. ...

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! ...

Some peculiarities of orbits of observed comets. ... Icarus, 2005 Simulation and reality Distribution of anti-perihelia of short-period comets with e 0.9 ( ecliptic coordinates ) Distribution of anti-perihelia of short-period comets with e 0.9 ( ecliptic coordinates ) Distribution of anti-perihelia of long-period comets with 0.9 e 1 ( ecliptic coordinates ) ­ ...

The new view on the population of Galactic open clusters A.E.Piskunov1, N.V.Kharchenko2, S.RЖser3, E.Schilbach3, R.-D.Scholz4 1 2 3 4 Institute of Astronomy, Moscow, Russia Main Astronomical ... Observatory, Kiev, Ukraine Astronomisches Rechen-Institut, Heidelberg, Germany Astrophysikalisches Institut Potsdam, Germany What are open clusters and what do they teach us Groups of Population I ... Cluster complexes: OCC-1 = Gould's Belt cluster complex? ...

Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 02 - 08.03.2015, Forecast on 09 - 16.03.2015, Carrington Rotation 2161 (27,93.03.2015) SUNSPOT-FORMING ACTIVITY OF THE SUN REMAINED AT THE AVERAGE LE- VEL, BUT IN THE LAST 2 DAYS OF THE PERIOD - ALREADY ON THE LOW. ... NEXT WEEK EXPECTED THE LOW LEVELS OF SUNSPOT ACTIVITY. ... BY DATA OF CORONOGRAPHS SOHO AND STEREO WERE OBSERVED >36 CME FROM WHICH THREE WERE "PARTIAL HALO II" TYPE. ... SOLAR FILAMENT ON 27.03. ...

... Cepheids and star groupings Sternberg Institute, Moscow University, 1983 Professor, 1997 Employment: 2000 -present Main sciential fellow, Sternberg Astronomicl Institute (SAI) of Moscow State University 1989 - 2000 Head of the Department for Galactic and Variable Stars Researches, SAI 1986 - 1989: Leading Scientific Fellow, SAI 1973 - 1986: Senior Scientific Fellow, SAI 1960 - 1973: laborant, aspirant ... 22, 161, 1978 3) Star complexes. ... Astron. ... Large scale star formation in galaxies. ...

Astronomy Discussion Forums . ... I Expected More Sense Than That. ... Post Message | ... Posted by Richard D. Stafford, Ph.D. on November 8, 2002 04:14:05 UTC . ... You are missing the point - harvey1 - November 8, 2002 - 13:10 UTC . I hope Stafford doesn't mind my intruding his forum - mrsouza - November 8, 2002 - 14:55 UTC . ... www.astronomy.net . ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... Our Milky Way galaxy is host to a number of companions. These companions are gravitationally bound to the Milky Way and are stellar systems in their own right. They include a population of about 150 globular clusters (GCs) and some 30 dwarf satellite galaxies (DSGs). ... These DSGs are more extended and diffuse compared to GCs. In fact the larger satellites of the Milky Way (and other galaxies, for that matter) host their own small systems of GCs. ...

Next: Polarization efficiency: size/shape/orientation effects Up: Optical properties of cosmic Previous: The 2175? feature . To model the interstellar polarization one needs to calculate the forward-transmitted radiation for an ensemble of non-spherical aligned dust grains. ... Let non-polarized stellar radiation passes through a dusty cloud with a homogeneous magnetic field. ... The angle between the line of sight and the magnetic field is ( ). ... where the angle is connected with and ( ). ...

... LMC Project Outline . NGC 1818 Initial Results . ... The Large Magellanic Cloud (LMC) is uniquely suitable for the study of massive star clusters at all stages of evolution. By combining HST observations of these clusters with N-body models we hope to understand the origin and evolution of rich star clusters in our own Galaxy, in the LMC, and beyond. ... We aim to combine our HST observations with N-body models to understand the formation and evolution of globular clusters. ...

... 319, P L1-L4 (1997). ... Article in PDF format (128 KB) . ... 319, P L9-L12 (1997). ... 319, P L13-L16 (1997). ... 319, P L17-L20 (1997). ... 319, P L21-L24 (1997). ... 319, P L25-L28 (1997). ... 319, P 729-736 (1997). ... 319, P 737-746 (1997). ... 319, P 747-756 (1997). ... 319, P 757-763 (1997). ... 319, P 764-780 (1997). ... 319, P 781-787 (1997). ... 319, P 788-795 (1997). ... Using the Earth orientation parameters to link the Hipparcos and VLBI reference frames . ... helpdesk@link.springer.de ...

... Magnetic storms online . ... Geomagnetic activity forecast . ... September : 2015 . ... No magnetic storm is expected . From 10 September 2015 to 6 October 2015 the following magnetic storms and disturbances are expected: . October 05, 2015 geomagnetic disturbances . September 12, 2015 geomagnetic disturbances . ... September 21, 2015 geomagnetic storm of level G1 (minor) . ... September 20, 2015 geomagnetic disturbances 10 September 2015 - 6 October 2015 . 09.09.2015 . ...

... Запорожский клуб АЛЬТАИР > . Catalogue of 109 new Galactic open clusters, for Cartes du Ciel . ... Cartes du Ciel - Sky Charts . ... Этот каталог является версией части каталога "J/A+A/440/403 109 new Galactic open clusters (Kharchenko+, 2005) ", а именно файла stars.dat, содержащего информацию о 26778 звездах до 14.627m , находящихся в 130 рассеяных скоплениях района Млечного Пути (Galactic Open Cluster). ... We present a list of 130 Galactic Open Clusters, found in the All-Sky . ...