Helium Star A980: IIA Finds Rare Germanium-Rich Star
Why in the news
Researchers at the Indian Institute of Astrophysics (IIA), Bengaluru, reported a rare germanium-rich make-up in the helium star A980. The result questions present ideas about where heavy elements are made.
Key facts
- Star: A980, a cool extreme helium (EHe) star.
- Finding: first detection of singly ionised germanium (Ge II) in such a star.
- Abundance: about eight times the solar value.
- Location: constellation Ophiuchus, roughly 25,800 light years from Earth.
About EHe stars
Extreme helium stars are rare evolved stars made almost entirely of helium, with very little hydrogen. They are thought to form when a helium-rich white dwarf merges with a carbon-oxygen white dwarf.
Why it matters
Existing models say heavy elements such as germanium arise in supernovae or AGB stars, not in EHe stars. The high germanium level in A980 hints that such elements may also form during white dwarf mergers, so the theories of nucleosynthesis may need revision.
Exam angle
- Note the institute: Indian Institute of Astrophysics, Bengaluru.
- Remember the element, germanium, and the star type, extreme helium star.
- Useful for science-technology current affairs in UPSC and State PSC papers.