Abstract -- Abundances of heavy elements decreases with increasing galactocentric distance almost in all disk galaxies. ... To explain this gradient in young objects and in the interstellar gas one has to assume that a typical disk galaxy is an open system, i.e. it expels some synthesized heavy elements into the circumgalactic space and/or accretes intergalactic gas with zero metallicity, with rates of both processes depending on the galactocentric distance. ...

An Ancient Universe: How Astronomers Know the Vast Scale of Cosmic Time . ... d) The Age of the Chemical Elements . ... Some isotopes (forms of the element with different numbers of neutrons in the nucleus) of these elements are radioactive; they change into other isotopes at a rate that can be measured accurately in the laboratory. ... The Ancient Universe - The Age of the Expanding Universe - The Age of the Oldest Stars - The Age of Light From Distant Galaxies - The Age of the Chemical Elements | ...

A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are: 06 (08.01.1; 08.03.2; 08.09.2 HD 144941; ASTRONOMY AND ASTROPHYSICS 9.10.1996 The iron abundance in helium star HD144941 ? ... The iron abundance in the helium star HD144941 has been measured from ultraviolet Fe iii lines. ... Pulsations in helium stars The improved iron abundance indicates a fractional heavy element abundance (by mass) of Z = 0:00024 and that the iron­group abundances follow the CNO abundances. ...

... Astrophysics Group . ... COAST . COAST Astronomical Results . ... Surface Imaging of Betelgeuse . ... This page highlights some astronomical results obtained with COAST over the years. These are listed in chronological order (most recent first). ... Measurements of cyclic variations in the angular diameter of Chi Cygni . ... The first infrared image from an aperture synthesis array . ... The images of Betelgeuse below were reconstructed from COAST data taken in early 2004. ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

... A form allowing access to any MPEC is at the bottom of this page. ... Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Prepared using the Tamkin Foundation Computer Network MPC @CFA.HARVARD.EDU URL http://www.minorplanetcenter.org/iau/ mpc .html 2010 NJ1 Observations: K10N01J * K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J K10N01J ... C51 WISE. ...

... 2002 July 25 . NGC 1569: Heavy Elements from a Small Galaxy . ... Still, heavy elements can profoundly influence galaxy and star formation ... not to mention the formation of planets and people. In this tantalizing false-color x-ray image from the orbiting Chandra Observatory , small dwarf galaxy NGC 1569 is surrounded by x-ray emitting clouds of gas thousands of light-years across. ... About APOD | ...

The problem of solar wind data correlation for the observations onboard several spacecraft is very important for three points of view: . ... This problem is studied now in detail by systematic determination of ion flux and ion velocity data correlations by INTERBALL-1 (IKI group), WIND and IMP 8 (both - MIT group). ... Solar wind plasma correlation lengths from IMP 8, WIND and INTERBALL-1. ... Correlation of solar wind observations onboard several spacecraft: INTERBALL-1, IMP 8 and WIND data. ...

... We can not observe the Universe when it is 1000 years old because a) there was no matter \b there were not photons \c the universe was opaque to radiation \d the speed of light was still changing at that time \e it had not begun its expansion \m Which of the following is a prediction ... heliocentric model for the Sola r System? \m \a stellar parallax \b retrograde motion \c Venus would never be observed at midnight \d different constellations would be seen at ...

... The department was founded in late sixties by Prof. D.Ya.Martynov, who for many years was also the director of Sternberg Astronomical Institute. At present time, the head of the department is Prof. A.M.Cherepashchuk, a pupil of D.Ya.Martynov and his successor as the director of SAI. Since Prof. Martynov, the scientific activity of the department was primarily related to binary stars. ... The department consists of 15 members most of which have Ph.D. in Astrophysics. ...

OBSERVATIONS OF COORBITAL SATELLITES OF SATURN Emel'yanov N., Varfolomeev M. Sternberg State Astronomical Institute, Moscow, e-mail : emelia@sai.msu.ru Institut de MИcanique CИleste et de Calcul des иphИmИrides, Paris, e-mail : emelia@imcce.fr Abstract. To improve the orbital parameters and masses of coorbital satellites of Saturn, Janus and Epimetheus, new observations of these satellites are necessary. ... IN: Saturn. ... New observations of Saturn's coorbital satellites" - Icarus. ...

STEP INTO THE BLUE - MEADE INSTRUMENTS PRODUCT GUIDE . ... Telescopes . ... Meade Series 5000 HD-60 6.5mm 6-Element Eyepiece (1.25") . ... Meade Series 5000 6.5mm HD-60 6-Element Eyepiece, #07730 (1.25"). The latest advancement in the Meade Series 5000 eyepiece series offers a large 60 apparent field of view and a flat field of view which is tack sharp right to the edge. ... Meade Series 5000 Pl ssl Eyepieces offer a very wide field-of-view, with pinpoint edge of field sharpness and contrast. ...

... B.V. Somov . head of the department . ... room 80 . ... senior research felow . ... research felow . ... research fellow . ... Our department performes the following most perspective studies: . Special analytical and numerical experimental investigations of the solar plasma involved in the magnetic reconnection process at the Sun. ... Head of the seminar: Prof. B.V. Somov. ... 27 September 2013 The Solar Physics Department was visited by journalists of the leading Russian TV channel "Vesti-1". ...

GRANAT is the Russian x-ray sattelite launched to the high apogee orbit (200,000 km) and operated almost for 10 years (1989 -1999) , carrying out four major instruments: French SIGMA coded-mask hard x-ray telescope (30-1000 keV), Soviet ART-P coded-mask telescope (2??-60?? keV), all-sky monitor WATCH (6-150 keV), and a gamma-burst detector PHEBUS . ... Since September 1994, GRANAT is in the survey mode. ... Explore pages devoted to individual GRANAT instruments (including main scientific results): . ...

... Astronomy of the Earth's motion in space. ... For easier reading, view this site with size 14 font (but print out with size 10 or 12 ). ... Stargazers" files are also available as a TARed and GZIPed file via anonymous FTP . ... Discovery of the Solar System . ... Kepler's First Law of Planetary Motion . ... 29a. Satellites observing the Sun, solar system and the universe . ... Orbits in Space . ... From Stargazers to Starships" follows an earlier site "The Exploration of the Earth's Magnetosphere" ....

... Fitting the observed dependence includes calculations of the polarization cross-sections averaged over particles orientation and size distribution, their normalization and the comparison of obtained dependencies with Serkowski's curve representing observational data for a chosen star. ... Variations of the polarization factors with wavelength are shown in Fig. 16 for homogeneous spheroidal particles with PF orientation. ... The distinction between prolate and oblate spheroids is also clearly seen. ...

Astronomy Discussion Forums . ... What I See . ... Follow Ups | Post Message | ... I have observed the Double Cluster, the BeeHive cluster and other open and various Globular Clusters. My main problem with my 114mm reflector is in its inabliity to bring deep sky objects. ... www.astronomy.net . About Astronomy Net | Advertise on Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... SSAU History . SSAU roadmap . ... Engineers of SSAU laboratory of additive technologies started to carry out experiments in the field of 3D-printing of metal parts, components and assemblies. The research of Samara scientists will allow producing highly complex and non-standard elements of spatial forms required for design and creation of advanced aviation and space technology. ... SSAU Laboratory of Additive Technologies is established in 2011. ... e-mail: ssau@ssau.ru . ...

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. ...