... 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. ...

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 ]. ...

... The absolute flux calibration of NICMOS will be calculated from observations of standard stars with known flux distributions F( ). ... In order to expand the set of IR standard stars in the appropriate flux range for NICMOS, M. Rieke, R. Thompson, and collaborators at the University of Arizona are making photometric observations of solar-analog stars, which will be used to normalize the solar spectrum to the observed IR magnitudes. ... Relative flux references accurate to 1.5% for standard...

... Science . ... Science Users Information > Observing with ESO Telescopes > Observing Tools and Services > Standard Stars Catalogues > Standard Star Catalogue Search Tool . ... Publications with ESO Data . ... ESO Data . ... This tool searches the standard star catalogues for standards that are within dX airmasses of the target at a given LST. ... In this case put the LST when the target was observed in the TargetLST box as before, and put the LST of the standard star observation in the StdObs LST box...

... A total of 19 standard observing bands are defined at the VLA. ... The tables below describe the bands. ... VLA STANDARD BANDS - VLA SYNTHESIZER SETTINGS VLABAND VLAFEAB VLAFECD VLASYNA VLASYNB FLUKEA FLUKEB FEFILT CC 0.00 0.00 3860.1 3810.1 100.00000 200.00000 0000 UU 19.60 19.60 3610.1 3660.1 100.00000 200.00000 0000 KK 17.60 17.60 3860.1 3810.1 100.00000 200.00000 0000 LL - 3.20 - 3.20 3639.9 3560.1 100.00000 200.00000 0000 XX 13.40 13.40 3939.9 3889.9 ...

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: . ...

Next: HKPARMINT Up: Generation from In-Orbit Data Previous: Wavelength calibration Contents . Spectroscopic Standard stars, mainly white dwarfs, were observed with both OM grisms. The ISF is obtained by dividing the extracted spectrum, in count rate versus wavelength, by the standard flux of the star obtained from HST Calspec database. The results obtained from several stars are then averaged and the standard deviation is taken as the error in the ISF. ...

... This routine is designed to read in the current correlator set-up, go to the chosen source, and then take data pointing directly at the specified source. This routine will automatically wait until you are on source before beginning to take data. ... Additionally, this routine allows you to take an ON/OFF calibration pair (one 10s scan with the noise diode on, followed by a 10s scan with the diode off), using the chosen noise diode configuration (see Section 1.6 . ...

... Archives . ... His foremost knowledge and historic account on statistical models related to errors may benefit astronomers. Although I didn?t study history of astronomy and statistics, I?m very much aware of how astronomy innovated statistical thinking, particularly the area of large sample theory. ... On the history and use of some standard statistical models . ... The particular reason for this paper into the slog is the following sentences: . ... Chandra Blog . ML Theory . ...

... 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. ...

Next: Definition of Scientific Misconduct Up: scientific Previous: Introduction . ... This Code of Good Practice closely follows the Statement on Safeguarding Good Scientific Practice issued by the Biotechnology and Biological Sciences Research Council (BBSRC) in 1998. ... The Observatory expects the highest standards of scientific integrity to be adhered to by the researchers, students and other staff that it funds, whether they are employees or associates of other institutions. ...

... References: % observed energy levels : Shirai,T., Sugar,J., Musgrove,A., Wiese,W.L., 2000, J.Phys.Chem.Ref.Data, Monograph 8 % observed energy levels (12,21,22,25,29,34,37,39-42): Martin,W.C., Sugar,J., Musgrove,A., Dalton,G.R., 1995, NIST Database , Version 2.0, NIST Standard Reference Database 61. %comment: the following NIST observed energy ... References: %filename: fe_23.splups %oscillator strengths (n=2 levels): Zhang, H.L., Sampson. ...

... We publish 16 Doppler imaging temperature maps for the years 1994-2002 of the active RS CVn star II Peg. ... Through Doppler imaging we want to study the spot evolution of the star and in particular compare this with previous results showing a cyclic spot behaviour and persistent active longitudes. ... The derived temperature maps are quite similar to the ones obtained earlier with a different methods, the main differences occurring in the spot latitudes and relative strength of the spot structures....

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: Buffer Manipulation Up: Programming in C Previous: Compiler Options . Listed below are nearly all the ANSI C standard library functions. The header file where related definitions are stored are given. These may vary on some systems so check local reference manuals. ... More info can be obtained from online man calls or reference manuals. Buffer Manipulation . Character Classification and Conversion . ... File Manipulation . ... Wed Sep 14 10:06:31 BST 1994 ...

The rise time of the normal Type Ia SN 1990N Paolo A. Mazzali 1 and Brian P. Schmidt 2 1 Osservatorio Astronomico, Trieste, Italy 2 Mt. ... If a standard density distribution ( / r 7 ) and composition for the SN ejecta are used, and the Cepheid distance modulus to the host galaxy, NGC4639 in the Virgo cluster,  = 32:00, is adopted, the 14d spectrum of SN 1990N is best reproduced if the epoch is t = 5  1 days, implying for the SN a rise time of 19  1 days. ...

... 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. ...

... 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 | ...

This section of library contains information about "classic" Star Catalogs. ... For a Henry Draper Catalog 272149 stars have received a total of 531,211 identifications in 7 сatalogs: . 270456 - in Astrographic Catalogue ( "Carte du Ciel", 4M), . 251943 - in Guide Stars Catalog (GSC), . ... A file with information on the components of 1788 of multiple systems in catalog HDEC (3681 component, or a combination thereof, with 4054 recording). ... A file with information about 21971 variable stars. ...

home education > resources . ... Education from Mercury . ... Selected Topical Bibliographies . Astronomy Education Bibliography . ... Astronomical Pseudo-Science . ... Foothill College the Astronomical Society of the Pacific) . ... Sletteback, A. Jettner, F. "Proceedings of the Conference on Education in Astronomy, August 1969" in Bulletin of the American Astronomical Society, vol. 2, p. 254 (1970). ... Accompanied, later in the same book, by a "Catalog of National Astronomy Education Projects".) ...