PG 1159 star
PG1159 star refers to a special class of stars that are in their stellar evolution between the red giants and the final white - dwarf stage. About 10 percent of all white dwarfs manages one last time, the helium fusion to ignite (helium flash ) and thus reach again the giant stage before they finally burn to a white dwarf. PG1159 stars are in this final stage of development and are characterized by the unique chemical composition of its atmosphere. In contrast to other stars it contains almost no hydrogen and instead of helium, carbon, and oxygen dominated.
The surface temperatures of PG1159 - stars are extremely high and are 70000-200000 K. The PG1159 star with the catalog name H1504 65 is true with 200,000 K as the hottest known star at all, and made it in 2004 to an entry in the Guinness Book of Records.
The Star class is named after the discovered in the Palomar -Green survey star PG1159 -035. Currently (February 2007 ) are known about three dozen objects of this type.
- K. Werner, T. Rauch:. Rebirth of the red giant. In: Stars and space. 2/2007, Spectrum Publishing, ISSN 0039-1263
- Article of the University of Tübingen
- Star class