PG 1159-035 explained

PG 1159-035 is the prototypical PG 1159 star after which the class of PG 1159 stars was named. It was discovered in the Palomar-Green survey of ultraviolet-excess stellar objects and, like the other PG 1159 stars, is in transition between being the central star of a planetary nebula and being a white dwarf.^[1]

The luminosity of PG 1159-035 was observed to vary in 1979,^[2] and it was given the variable star designation GW Vir in 1985.^[3] Variable PG 1159 stars may be called GW Vir stars, or the class may be split into DOV and PNNV stars.^{[4] [5]} The variability of PG 1139-035, like that of other GW Vir stars, arises from non-radial gravity wave pulsations within itself.^[6] Its light curve has been observed intensively by the Whole Earth Telescope over a 264-hour period in March 1989, and over 100 of its vibrational modes have been found in the resulting vibrational spectrum, with periods ranging from 300 to 1,000 seconds.^{[7] [8]}

Notes and References

1. 2007A&A...462..281J . High-resolution ultraviolet spectroscopy of PG 1159-035 with HST and FUSE . Jahn . D. . Rauch . T. . Reiff . E. . Werner . K. . Kruk . J. W. . Herwig . F. . Astronomy and Astrophysics . 2007 . 462 . 1 . 281 . 10.1051/0004-6361:20065901 . astro-ph/0610592 . 17679220 .
2. 1979wdvd.coll..377M . PG 1159-035: A New, Hot, Non-Da Pulsating Degenerate . McGraw . J. T. . Sumner Starrfield . Starrfield . S. G. . Liebert . J. . Green . R. . IAU Colloq. 53: White Dwarfs and Variable Degenerate Stars . 1979 . 377 .
3. 1985IBVS.2681....1K . The 67th Name-List of Variable Stars . Kholopov . P. N. . Samus . N. N. . Kazarovets . E. V. . Perova . N. B. . Information Bulletin on Variable Stars . 1985 . 2681 . 1 .
4. 2004A&A...426L..45N . Detection of non-radial g-mode pulsations in the newly discovered PG 1159 star HE 1429-1209 . Nagel . T. . Werner . K. . Astronomy and Astrophysics . 2004 . 426 . 10.1051/0004-6361:200400079 . astro-ph/0409243 . 9481357 .
5. 2007ApJS..171..219Q . Mapping the Instability Domains of GW vir Stars in the Effective Temperature-Surface Gravity Diagram . Quirion . P. -O . Fontaine . G. . Brassard . P. . The Astrophysical Journal Supplement Series . 2007 . 171 . 1 . 219 . 10.1086/513870 . 122695910 .
6. 10.1088/0953-8984/10/49/014 . Asteroseismology of white dwarf stars . 1998 . Winget . D. E. . Journal of Physics: Condensed Matter . 10 . 49 . 11247–11261 . 1998JPCM...1011247W . 250749380 .
7. 1991ApJ...378..326W . Asteroseismology of the DOV Star PG 1159-035 with the Whole Earth Telescope . Winget . D. E. . Nather . R. E. . Clemens . J. C. . Provencal . J. . Kleinman . S. J. . Bradley . P. A. . Wood . M. A. . Claver . C. F. . Frueh . M. L. . Grauer . A. D. . Hine . B. P. . Hansen . C. J. . Fontaine . G. . Achilleos . N. . Wickramasinghe . D. T. . Marar . T. M. K. . Seetha . S. . Ashoka . B. N. . O'Donoghue . D. . Warner . B. . Kurtz . D. W. . Buckley . D. A. . Brickhill . J. . Vauclair . G. . Dolez . N. . Chevreton . M. . Barstow . M. A. . Solheim . J. E. . Kanaan . A. . Kepler . S. O. . The Astrophysical Journal . 1991 . 378 . 326 . 10.1086/170434 . 10183/108718 . 1 . free .
8. 2008A&A...477..627C . The pulsation modes of the pre-white dwarf PG 1159-035 . Costa . J. E. S. . Kepler . S. O. . Winget . D. E. . O'Brien . M. S. . Kawaler . S. D. . Costa . A. F. M. . Giovannini . O. . Kanaan . A. . Mukadam . A. S. . Mullally . F. . Nitta . A. . Provençal . J. L. . Shipman . H. . Wood . M. A. . Ahrens . T. J. . Grauer . A. . Kilic . M. . Bradley . P. A. . Sekiguchi . K. . Crowe . R. . Jiang . X. J. . Sullivan . D. . Sullivan . T. . Rosen . R. . Clemens . J. C. . Janulis . R. . O'Donoghue . D. . Ogloza . W. . Baran . A. . Silvotti . R. . Astronomy and Astrophysics . 2008 . 477 . 2 . 627 . 10.1051/0004-6361:20053470 . 0711.2244 . 6762152 . 1 .