Astronomers Discovers the Small, Hot Helium Star

GS Paper III Science and Technology

Context:

Astronomers have discovered a rare class of stars, called helium-covered hot stars.

After the research, scientists finally discovered a missing population of stars that confirms a key prediction of how Binary Star evolved.

Binary Star

A system of two stars in which one star revolves around the other or both revolve around a common centre.

Also Read: Formation Of Stars

It is a class O or B star (blue), which has extraordinarily strong helium lines, and weaker than normal Hydrogen lines, indicating strong stellar winds.

Class O or B Star

Class O: It includes bluish-white stars with surface temperatures typically 25,000–50,000 K.
- Lines of ionized helium appear in the spectra.
Class B: These stars typically range from 10,000 K to 25,000 K and are also bluish-white but show neutral helium lines

- Extreme Helium Stars are scarce stars that are almost completely devoid of hydrogen.
Temperature: Helium-rich stars are the hottest star category, almost 10 times as hot as the Sun.
- Their immense heat means that despite being exceptionally rare, they make an outsize contribution to the universe’s stock of heavier elements.
Hypothetical Star: A Helium star is also a term for a hypothetical star that could occur if two helium white dwarfs subsequently start nuclear fusion of helium, with a lifetime of a few hundred million years.
This may only happen if these two binary masses share the same type of envelope phase. It is believed this is the origin of the extreme helium stars.

Also Read: Black Hole Mass Gap

News Source: ILF Science and The Hindu

Must Read
NCERT Notes For UPSC	UPSC Daily Current Affairs
UPSC Blogs	UPSC Daily Editorials
Daily Current Affairs Quiz	Daily Main Answer Writing
UPSC Mains Previous Year Papers	UPSC Test Series 2024