... Stellar Evolution is driven entirely by the never ending battle between Pressure and Gravity . As imbalances are reached, the star is driven to find a new Energy source. ... Pressure and gravitational forces are equal, the star is stable and its core is sufficiently hot to fuse Hydrogen into Helium More about main sequence stars . ... The luminosity generated by the core fusion of Helium into Carbon is far greater than the shell luminosity associated with the fusion of Hydrogen into Helium. ...

... 172 ] Briefly, the count rate at the detector from a source at a redshift z is . ... Figure 55 shows the ``Green functions'' for the double compact binary merging rate   evolution assuming no collapse anisotropy. ... Another way that diverse peculiarities in the - distribution induced by the sources evolution could arise is connected with a possible non-monotonic character of the star formation rate in galaxies. ... 22 ] Figure  56 shows two-dimensional cuts through the parameter space. ...

Morphology and Models of Faint Galaxy Counts D.C. Koo University of California Observatories/Lick Observatory University of California, Santa Cruz Most models of faint galaxy counts continue to rely on transforming observed distributions of morphology of local galaxies to estimate the distribution of K corrections. ... For example, at B ё 24, our no­evolution models predict counts that are only 50% shy of the observed (Koo, Gronwall, & Bruzual 1993, ApJL, 415, L21). ...

The project of the informational system creation on the problem of evolution of radio galaxies, as a part of the "Big Trio" project aimed on studing of distant radio galaxies, is designed. This system allows a user to operate with simulated curves of spectral energy distributions (SED) to estimate ages and redshifts by photometry data. Authors use SEDs of several models for different types of galaxies. ... The HTTP and e-mail access is organized to this system. ...

During the course of its evolution, the Sun has accreted substantial quantities of material in the form of asteroids, comets, planetesimals and proto-planets. This debris is poor in hydrogen and helium and has substantially enriched the metallicity of the solar surface which must consequently be higher than that of the unobserved core. ... The solution may also explain the Faint Young Sun paradox and the inclination of the solar equator relative to the ecliptic. ...

Next: Reduction procedure Up: Extinction and transformation Previous: Strategy . Standard stars can be included in the extinction solution, if one is careful. The problem is that there are usually appreciable ``conformity errors'' due to mismatch between the instrumental and the standard passbands [ 16 ]. ... Thus, it is wrong to assume that the transformation between the instrumental system and the standard system is exact, even if there were no measurement error in either system [ 1 ]. ...

... Superb optical performance coupled with time proven computerized pointing and tracking has made the LX200 ACF series a best-seller in the high-performance telescope class. ... MeadeтАЩs new LX70 Series offers high-quality German equatorially mounted telescopes with slow-motion controls and heavy-duty steel tripods. ... For crisp wide-field observing and imaging, few optical designs match the performance of a true triple-element apochromatic refractor. ... Meade Standard Field Tripod #07020. ...

... Science Users Information > Science and Technical Meetings > Conferences 2010 > The Origin and Fate of the Sun: Evolution of Solar-mass Stars Observed with High Angular Resolution . ... Observing Facilities . ... Observing with ESO Telescopes . ... The goal of this workshop is to review recent results on solar-mass stars obtained with infrared and millimeter interferometers, and to discuss their importance for our understanding of stellar evolution from star formation to stellar end products. ...

... Australia Telescope Steering Committee . ... Parkes radio telescope . ... Late Stages of Stellar Evolution . Welcome to the home page of the Late Stages of Stellar Evolution" We are a research group which operates within the Astrophysics Group of the Australia Telescope National Facility. ... To investigate the late stages of stellar evolution and in particular the role of stellar mass-loss in the evolution of asymptotic giant branch stars, proto-planetary nebulae and extremely massive stars. ...

... Using the self-consistent 3D hydrodynamical code in Kobayashi et al. (2007) , we simulate the star formation and chemical enrichment history of the Universe. ... We also predict the rates of supernovae and gamma-ray bursts, and the properties of the host galaxies, which will be observed with the ANU's new SkyMapper telescope. ... Supernova feedback on galaxy formation. ... Feedback from active-galactic nuclei (AGN). ... COALA : Universe Galaxy AGN Star Planet ...

... VLA observations and Tully-Fisher distances of gas-poor spiral galaxies in the Virgo Cluster Region . ... The HI-H2 Pressure Relation In Early-Type Galaxies . ... Tracing evolution of early-type spirals through the neutral hydrogen window . ... An Arecibo HI 21-cm Absorption Survey of Rich Abell Clusters . ... The Arecibo Ultra-Deep Survey . ... Absorption in varying galactic environments seen in HI surveys . ... Early-type galaxies with neutral hydrogen in the Virgo cluster from the ALFALFA survey ...

... Galaxy Evolution home . ... Regulating the ISM and star formation . Cosmological evolution of star-forming galaxies . ... Local Information . ... In order to investigate the cosmological evolution of star-forming galaxies it is essential that we understand the physics which controls the evolution and regulation of star formation in the ISM. ... We use a combined observational and numerical approach to study interacting and merging galaxies in the local Universe. ...

... Tonight's Sky . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . The Golden Earring, planetary nebula NGC 2867, and barred spiral galaxy NGC 3109 . Open cluster NGC 2818, spiral galaxy NGC 2964, and spiral galaxy NGC 2976 . ... Dwarf galaxies donт??t fit standard model . ... DWARF GALAXIES | ...

Last updated 5 November 2003 by JMD . Last link checked 9 October 2003 by JCB . Data from 191 observations of stars with the ARCES were analyzed to calculate exposure times to reach particular signal-to-noise values for bright standard stars. ... An exponential fit to the data shows pretty good agreement and allows for forecasting to fainter stars beyond the limit of the data set ( V ~ 12). The fit was used to calculate the exposure times in the table below: . ...

... The material in "From Stargazers to Starships" meets several important requirements of the national standards. Pages cited below are from National Science Education Standards National Academy Press, Washington 1995. ... For example: the sections on astronomy not only describe calendars and sundials (including their construction), but also the astronomy of the ancient Greeks, including two different ways in which ancient Greeks estimated the distance to the Moon. ...

... A Hubble diagram for Quasars . ... The potential use of such relation as a cosmological probe is obvious: assuming no redshift evolution of the relation, the observed X-ray flux is a function of the observed UV flux, the redshift, and the parameters of the adopted cosmological model. ... In this framework, Guido Risaliti and Elisabeta Lusso (INAF-Arcetri Observatory) have recently published in the Astropysical Journal the first Hubble Diagram for quasars suitable for cosmological measurements . ...

Solar Flare Origin - critical analysis" Lev Pusti'lnik We analyze current approach to solar flare origin in 3 aspects: a. Pre-flare equilibrium state of current-magnetic structure above active region and its evolution to flare state, b. Possible reasons of stability loss with transition of system in flare state c. Flare energy release in turbulent current sheet and particle acceleration in this system. ...

Emission Line Diagnostics in a ``No UV Bump'' Quasar PHL909 Smita Mathur, Belinda Wilkes, Martin Elvis and Jonathan McDowell Abstract PHL909 is a quasar with unusually low ultraviolet luminosity (blue bump strength C UV=IR = \Gamma0:20 compared to an average value of 0:4 (McDowell et al. ... The intrinsic continuum of PHL909 ( i.e. as seen by the BELR ) may thus be similar to the `standard' continuum, with a big blue bump, reddened along the line of sight. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Space Flight . ... Earth Satellites . ... Leonid meteors seen from 13 km altitude aboard an aircraft during the 1999 Leonids Multi-Instrument Aircraft Campaign (Leonid-MAC). Comet Tempel-Tuttle provides the cometary debris for the Leonid meteor shower. ... Every 17-19 November Earth crosses Tempel-TuttleтАЩs orbit and the Leonids become visible. With clear, dark skies observers may see 10 to 15 Leonid meteors every hour on those mornings. ...

Next: HST-NICMOS Observations of Galactic Up: NICMOS Science Previous: A Color Analysis of . ... Why choose NGC 1569? ... NICMOS Data in the Central Region of NGC 1569 . ... To have a census of the old stellar populations of the dwarf irregular galaxies NGC 1569 and NGC 1705 and to trace the major episodes of star formation over a Hubble time in these starbursting systems, we have applied for and obtained HST/NICMOS observations in the F110W and F160W bands with the NIC2 camera. ...