... 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. ...

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 ...

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 ]. ...

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. ...

... 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. ...

... Public . Science . ... Science Users Information > Observing with ESO Telescopes > Observing Tools and Services > Standard Stars Catalogues . ... Observing with ESO Telescopes . ... Publications with ESO Data . ... Large Programmes . ... ESO/GTC Programmes . Public Surveys Programmes . ... Phase 1 Proposals . ... Public Surveys Phase 2 . ... Science Data Products Forum . ... ESO Data . ... ESO Data Access Policy . ... Below follows a non-exhaustive list of on-line standard star catalogues. ...

... 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...

... 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 . ...

... 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. ...

. 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 .