... 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. ...

Function: MOMS Purpose: Given an data array, return (depending on mode) sum, mean, variance, standard deviation, absolute deviation, skewness, kurtosis or median. Category: MATH, STATISTICS File: moms.c Author: M.G.R. Vogelaar Description: The available routines are the following: MOMSF returns a moment value for a real array. MOMSD returns a moment value for a double precision array. Updates: Feb 20, 1995: VOG, Document created.

... 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 . ...

... Updates to HST Standard-Star Fluxes . ... These data are in an STScI data base named CRCALSPEC and have been divided into two categories to help the user understand the origin and accuracy of these flux distributions. ... 1990, ApJS, 73, 413) and Oke (1990, AJ, 99, 1621) spectra are available. Oke (1990) used the DoubleSpectrograph on the 5-m Hale Telescope to obtain these spectra for HST calibration; and these data are identified in the HST data bases by the keyword OBSMODE=OKE DBSP. ...

... Standard magnitudes can only be computed for the U, B and V filters and hence the only standard colours that can be calculated are U-B, B-V and U-V. An important point to note, is that these standard colours can be computed using the following instrumental colours - U-B, B-V, U-V, (UVW1-U), (UVW1-B), (UVW1-V), (UVW2-B) and (UVW2-V). ... The program loops through these colours and if the relevant instrumental magnitudes are present computes the standard magnitudes and standard colour. ...

... Apache HTTP Server Version 2.4 . Apache > HTTP Server > Documentation > Version 2.4 > Miscellaneous Documentation . ... This page documents all the relevant standards that the Apache HTTP Server follows, along with brief descriptions. ... http://www.rfc-editor.org/errata.php - RFC Errata . ... This document summarizes the history of HTML development, and defines the "text/html" MIME type by pointing to the relevant W3C recommendations. ... HTML documents are SGML documents. ...

... Apache HTTP Server Version 2.2 . Apache > HTTP Server > Documentation > Version 2.2 > Miscellaneous Documentation . ... This page documents all the relevant standards that the Apache HTTP Server follows, along with brief descriptions. ... http://www.rfc-editor.org/errata.html - RFC Errata . ... This document summarizes the history of HTML development, and defines the "text/html" MIME type by pointing to the relevant W3C recommendations. ... HTML documents are SGML documents. ...

. To append the standard output from a command to a file use two >> (greater than) symbols followed by the name of the file. If the file does not exist it is created. For example: cat part1 > chapt2 cat part2 >> chapt2 . This creates a file called chapt2 with the same contents as part1 . It then reads the contents of part2 and appends them to the file chapt2 . The file chapt2 now contains the data from part1 followed by the data from part2 .

... 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...

. This is the CIMA standard on/off menu: . The following is the on-line help page for standard on/off: . You can return to the main CIMA page by clicking here .

Bigbang Forum Message . Forums: . ... Discussion Forums | ... The Ekpyrotic [string] Models And The Standard Guth Model. Forum List | ... Post Message | ... Could you outline the differences between the Ekpyrotic [string] models and the standard Guth model? ... 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" . ...

... The first step to improve the FORS calibration is therefore to obtain data to allow a computation of the illumination correction across the field. ... Another limitation on the calibration accuracy has been the brightness of the Landolt standards which have forced the use of extremely short exposures introducing small but non-negligible shutter-time errors and also resulting in a very small number of useful standards per frame. ...

... The cross entropy for this complex image is given by ( 16 ) and ( 17 ). ... Differentiating ( 31 ) with respect to and , we find the gradient of is given by . and upon differentiating once more we find the Hessian (curvature) matrix of has the form . ... and its Hessian matrix reads . ... From ( 16 ) and ( 17 ), we find the components of the gradient vector of the cross entropy are given by . ... Differentiating once more we find the components of the Hessian of the cross entropy to be given by . ...

... Team . ... The main goal of observations of GRB host galaxies is accumulation of statistics of their spectroscopic and photometric properties. ... The Hubble diagram for 22 GRB host galaxies with known magnitudes and redshifts (GRB 970228, GRB 970508, GRB 970828, GRB 971214, GRB 980613, GRB 980703, GRB 990123, GRB 990510, GRB 990712, GRB 9912008, GRB 991216, GRB 000131, GRB 000210, GRB 000301C, GRB 000418, GRB 000911, GRB 000926, GRB 001109, GRB 010222, GRB 010921, GRB 011121 and GRB011211). ... 600...

The database contains references to the papers, data files and links to the Internet resources related to measurements and calculations of the optical constants in the wavelength interval from X-rays to radio domain. ... References to some useful books and reviews on the subject (e.g. the classical handbooks edited by E.D.Palik) and links to Internet collections of optical constants and personal WWW pages with related software were also placed in the database. You have arrived at our welcome page. ...

... Fortranљ66 . ... Fixed form . ... Whole Fortranљ66 . ... Continuation line indicated in column 6 . ... Blank line as comment . ... Extension in Unix .f .f .f .f90 .f .f90 . Extension in DOS .FOR .FOR .FOR .F90 .FOR .F90 . ... This applies to both fixed form and free form source code. ... Fixed form of the source code is discouraged in Fortran 95! ... In UNIX there is no concept called extension, and the extensions are not specified in the Fortran standard, but in informal manufacturer standards. ...

... 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. ...

... 237S (SIMBAD/NED BibCode) ================================================================================ Keywords: Sun: UV radiation - atmospheric effects - Sun: atmosphere - lines: identification Description: An ultraviolet atlas of the solar spectrum with a spectral resolution of 15mA in the region 1948-2000A is presented. ... The wavelength atlas with a list of about 550 lines has been synthesized from data at center of the Sun ({mu}=1) and at {mu}=0.89, smoothed out over an area of 30 arcsec. ...

... Up: Algorithms . ... Non-linear and non-parametric algorithms for data averaging, smoothing and clipping in the RATAN-600 flexible astronomical data processing system are proposed. Algorithms are based on robust methods and non-linear filters using an iterative approach to smoothing and clipping. ... The history of algorithms, based on the robust methods and non-linear filters using an iterative approach to smoothing and clipping, began twelve years ago in the data reduction at the RATAN-600. ...

After filling in and submitting this form it will be processed and sent to WDC for STP data manager responsible for the data of your interest. You will receive requested data by electronic mail according to your preference. ... High Atmosphere . ... Radiation Belts of Earth . International Geomagnetic Referece Field Model (IGRF) . Geomagnetic Field of the Earth (by N. A. Tsyganenko model) . E-mail . Additional arbitrary information can be written in the text window as follows. ...