... 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. ...

... 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...

Next: Examples of Setup Files Up: Setup Files Previous: Setup Files Contents . Over 200 standard setup files have been created, covering many of the normal modes of observing. ... These especially include precisely defined, and somewhat complex cases like the Mark III standard modes (although MarkIII went the way of the dinosaur long ago. ... v '' files: . These are setup files for VLBI observations using VLBA recording formats. ... These are setup files for Mark III observations. ...

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 ]. ...

... Science Users Information > Data Handling and Products > Data Reduction FAQ > Why are my spectra not flux calibrated, even though there are standard star observations in the data set? ... Observing with ESO Telescopes . ... ESO-MIDAS . ... Data Handling and Products . ... Data Pipelines and Calibrations . ... ESO Data . ... ESO Data Access Policy . ... If there is no reference table for the flux standard star no response curve is created and therefore the science data are not flux-calibrated. ...

Optical and UV Spectrophotometric Standard Stars . ... Two papers detail the observations: the first is devoted to wavelengths from 3300 to 7550A (Hamuy et al., ... -------------------------------------------------------- 718 Xi2 Cet B9 III -O.107 -0.056 4.279 -0.023 -0.063 1544 Pi2 Ori Al V 0.01 4.355 0.014 0.039 3454 Eta Hya B3 V -0.743 -0.200 4.295 -0.083 -0.200 4468 Theta Crt B9.5 V -0.18 -0.07 4.700 -O.023 -0.063 4963 ...

... 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 . ...

... 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. ...

XMM­Newton CCF Release Note XMM­CCF­REL­120 OM Photometry Bing Chen July 5, 2002 1 CCF components Name of CCF VALDATE List of Blocks changed CAL VERSION XSCS flag OM COLORTRANS 0007 2000­01­01T00:00:00 COLORMAG No 2 Changes The zero­points and color­transformations for optical filters are set based on observations of several hundreds standard stars. ... We can see that the simulated UV color­transformation based on this new CCF can represent the observations. ...

... The New 1997 IEEE Standards Products Catalog features the complete listing of standards publica-tions and services IEEE Standards offers, along with the information you need to place your order. ... Books and Other Products on Standards - contains a detailed listing of informative print and electronic publications relevant to standards and their implementation in areas of electrical engineering, electronics and computer technology. ... IEEE Standards Products Listing 22 . ... Power Electronics 41 . ...

. To redirect the standard input for a command use the < (less than) character followed by the name of the input file. For example: mail tony < memo . This redirects the standard input to the mail command so that it comes from the file memo . The effect of this is to mail the contents of this file to the user tony .