... Early studies of PMS stars focused on T associations, especially Taurus-Auriga. However, one might expect low mass star formation to be different in OB associations. ... He identified Orion OB1a as the stars northwest of the belt. Orion OB1b is composed of the stars near the belt, including the belt stars and Orionis. ... He finds no perceptible distance change within the Orion OB1b association and finds the distance modulus to be 7.8 and 7.9 for Orion OB1a and OB1b respectively. ...

Next: Other People's Software . ... Quality system management of computer workstations for astronomy can be achieved with relatively small manpower requirements, if the right cost-effective administrative design decisions are made. ... This is all done with essentially one system manager. ... The system is designed so that one doesn't depend on four or more hosts, (such as a software server, cpu server, data file server, font server, etc.) to get work done. ...

... HD144941 is a B type hydrogen-deficient star. ... However, its H/He ratio puts it between the classifications of an extreme and an intermediate helium star, and its low C and N abundances make it unique amongst known H-deficient stars. ... Keywords. stars: helium stars -- stars: individual stars (HD144941) -- stars: atmospheres -- stars: abundances -- stars: oscillations -- stars: evolution . ... The iron abundance in the helium star HD144941 has been measured from ultraviolet Fe III lines. ...

Authors: V.A. Marsakov , Yu.G. Shevelev , . Journal: 1988, Astron Zh. ... Absolute magnitudes, metallicities, effective temperatures, surface gravities, distances, and tangential velocities are calculated for 5498 F stars with homogeneous data on uvby photometry and proper motion, and placed within 80 pc from the Sun. Components of space velocities, eccentricities of galactic orbits, perigalactic and apogalactic distances, and maximal remotness from galactic plane are presented for 1787 stars. ...

... Observing . ... Solar Observing . ... April 3 (SUN) - Solar Observing, Central Park , Manhattan . ... APRIL'S SKY . ... Lecture Series at the American Museum of Natural History The Amateur Astronomers Association is proud to present an astronomy lecture series from October through May each year for our members and the .. ... The€аAmateur Astronomers Association of New York€аwas organized in 1927 to promote the study of Astronomy, emphasizing its cultural and inspirational value. ...

... По ПЗС-спектрам, полученным с эшелле-спектрометром PFES 6-м телескопа, впервые методом моделей атмосфер определены эффективная температура , ускорение силы тяжести и детальный химический состав слабой звезды, отождествляемой с ИК-источником . IRAS23304+6147. ... Значения эффективной температуры атмосферы объекта, полученные независимо методом моделей атмосфер и путем моделирования распределения энергии в оптическом и инфракрасном диапазонах, совпадают в пределах точности методов. ...

... The molecular content of the DMTau and GGTau disks . ... 317, P L55-L58 (1997). ... Article in PDF format . ... 317, P L59-L62 (1997). ... 317, P L63-L66 (1997). ... 317, P L67-L70 (1997). ... 317, P L71-L74 (1997). ... 317, P L75-L78 (1997). ... 317, P L79-L81 (1997). ... 317, P 303-317 (1997). ... 317, P 318-327 (1997). ... 317, P 328-349 (1997). ... 317, P 350-357 (1997). ... 317, P 358-384 (1997). ... 317, P 385-392 (1997). ... 317, P 393-396 (1997). ... helpdesk@link.springer.de . ...

... 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. ...

Mikhail Medvedev (University of Kansas) HEA- 2007 , IKI, Moscow Missing baryons in inter-cluster gas Afshordi, et al, 2007 , astro-ph/0612700 35% +/- 8% Sample of 260 clusters WMAP SZ 3yr data Compared with 11 simulated clusters Assumed: Universal NFW profile Self-similarity Isothermal gas Possible explanations Observed stellar mass in galaxies: ~ 10% (Lin, et al, ... Simulations indicate that the effect is small (Dolag, et al, 2004) Can account for ~1-2% missing mass at most ...

University Satellites and . Space Science Education . ... It is necessary to select a topic interesting from scientific point of view and simple enough to allow students understand and participate in all stages of experiment from measurements via data analysis to physical inference. ... Solar modulation effects and physical characteristics and analysis of the major solar events are possible only by joining data from space-born and surface particle and radiation detectors. ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...