Description

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Source: Youtube

Context

Scientists have found an interesting twist in the universe in the star A980, which is in a small group of stars called Extreme Helium (EHe) stars. This star has a lot of germanium, a metal that has never been seen in this type of star before.

What are helium stars?

Helium stars, also known as helium-burning stars, are a stage in the evolution of certain types of stars.
These stars are typically more massive than the Sun and have exhausted the hydrogen fuel in their cores, leading to a contraction and subsequent heating of the core.
As a result, helium fusion begins in the core, where helium nuclei fuse to form heavier elements such as carbon and oxygen.
This fusion process releases energy, causing the star to expand and become more luminous.
Helium stars represent an intermediate stage in stellar evolution between main-sequence stars and later stages such as red giants or supernovae.

About Extreme Helium Star

It is a supergiant with a low mass that doesn't have much hydrogen in it.
Strangely enough, these uncommon and mysterious stars seem to be mostly made up of helium instead of hydrogen, which makes up most stars like the sun.
It is thought that EHe stars formed when a carbon-oxygen white dwarf merged with a helium white dwarf that was less massive.
So far, 21 of them have been found in our galaxy.
These work at temperatures between 8000 K and 35000 K.
It was Daniel M. Popper of the University of Chicago who found HD 124448 at McDonald Observatory in Austin in 1942. It was the first star with extreme helium levels.

Key features of Germanium

Element Name	Germanium
Symbol	Ge
Atomic Number	32
Group in Periodic Table	Group 14 (IVa), between silicon and tin
Appearance	Silvery-gray metalloid
Type	Metalloid (intermediate between metals and nonmetals)
Crystal Structure	Diamondlike crystalline structure
Similar To	Chemically and physically similar to silicon
Stability	Stable in air and water
Reactivity	Unaffected by alkalis and most acids, except nitric acid

Source: PIB

Practice Question:

Q. With reference to Extreme Helium Stars (EHe stars), consider the following statements:

They are extremely rare stars with very low hydrogen content.

They are believed to be formed by the merger of two white dwarfs.

These stars are rich in helium and carbon.

Which of the statements given above is/are correct?

A) 1 and 2 only

B) 2 and 3 only

C) 1 and 3 only

D) 1, 2 and 3

Answer:

D) 1, 2 and 3

Explanation:

Statement 1: Correct. EHe stars are very rare and almost devoid of hydrogen, which is unusual since hydrogen is the most abundant element in most stars.

Statement 2: Correct. The most accepted theory is that they form through the merger of a helium white dwarf with a carbon-oxygen white dwarf.

Statement 3: Correct. These stars are composed mainly of helium and show a significant amount of carbon in their atmospheres.