... 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. ...

... Data Handling and Products > Data Reduction FAQ > The spectrum of my MOS flux standard star is shifted in wavelength by several pixels. Why is that and how can I correct for it? ... Observing with ESO Telescopes . ... The shift of the flux standard spectrum is caused by a combination of bad centering within the slit and possible wavelength calibration issues. To align the spectrum to the tabulated flux, use the parameter --resp_shift in vmmosscience when determining the response curve. ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Parkes radio telescope . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... We discuss variations of the atmospheric extinction coefficients and transformation equations to the standard UBVRI system based on observations of standard stars during 1996-1997 at Siding Spring Observatory using a thinned SITe CCD and coloured glass filters. ... Standard System Transformations . ...

... Current APO Weather . ... Search Site . ... Information for New Users . ... Technical Staff pages . Night Logs and Mailing Lists (maintained by APO) . ... Technical Documents and Database Search . ... Observer's Documentation and Procedures . ... Problem Reporting and APO Technical Documents Database Search . ... APO Drawing/Document Management Procedures . ... APO Technical Documents Database Search . Home Astrophysical Research Consortium . ... Mail Lists (maintained by APO) . ...

... We present easy-to-use web applications and XML Web Services to search, plot and manage spectral energy distributions and filter profiles. We provide keyword search, advanced query forms and SQL interfaces to select spectra and band passes that may be retrieved in a variety of formats including XML, VOTable and ASCII. ... We built a relational database of SEDs and implemented effective search algorithms as well as common spectrum and bandpass manipulation functions in the form of XML Web Services. ...

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The Astronomical Society of Australia has been asked by STANDARDS AUSTRALIA to compile a list of "designated" optical observatories that are valuable resources for (i) research, (ii) education and (iii) community use. The ASA is the final arbiter of whether any particular observatory is so designated. ... Upon receipt of your application form, your observatory will be entered on a list of "Pending Designated Observatories" on the ASA Home Page. ... It will be emailed for you. ... Email . ...

... 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 . ...

Open Systems Handbook: A Guide to Building Open Systems . ... This book is designed to provide interested individuals and organizations with an overview of open systems and the work being done to achieve them. ... This section is organized using a descriptive model of an open systems environment developed by the IEEE PI 003.0 Working Group, which is developing the Guide to POSIX-based Open System Architecture. ... Standards for open systems 13 . Chapter 3: The open systems environment (OSE) 15 . ...

Erratum: ``Northern JHK Standard Stars for Array Detectors'' [A.J. 115, 2594 (1998)] L. K. Hunt, F. Mannucci C. A. I. S. M. I. ­ C. N. R. L. Testi 1 , S. Migliorini 2 ... Astronomia, Universit`a di Firenze and C. Baffa, F. Lisi, L. Vanzi 3 Osservatorio Astrofisico di Arcetri Received ; accepted 1 Current Address : Osservatorio Astrofisico di Arcetri 2 Current Address : Dipartimento di Ingegneria, Universit`a di Firenze 3 Current ... K­band finding chart for AS­30. ...

Next: Observatory table Up: Star tables Previous: Multiple star files . Some standard-star files are supplied for the UBVRI and uvby-H-Beta systems. ... You can also make new tables of standard stars. The easiest way to make standard-star tables is to begin as though they were program-star tables, but to include columns of standard values in the ASCII file, and field descriptions for them in the format file, before running MAKE/STARTABLE . ...