Context: As per the study of Ministry of Science and Technology, scientists have found a clue to the mystery behind the high abundance of Lithium in some evolved stars.
Key highlights of the study

• A red giant star with high lithium abundance at its surface was discovered.
• About 1% of sun-like red giants had a lithium-enriched surface.
• The abundance of lithium was confirmed after the experts conducted a survey named GALAH.
• It provided a collection of 500,000 stars with lithium abundances.
• In order to find the origin, experts gathered the interior oscillations data in red giant stars that were found to have abundance of lithium.
• These stars have helium burning in their core.

About GALAH Survey

• The Galactic Archaeology with HERMES (GALAH) Survey is a project to observe a million stars in our Milky Way Galaxy.
• Aim: To understand to what extent the galactic disk’s composition is from stars that originated in other galaxies and merged with the Milky Way Galaxy.
• It allows detailed measurements to be made on 400 stars at a time.

Significance

• It will map out substructures of the early Milky Way galaxy to understand of how the Galaxy formed and evolved.
• It will provide accurate velocity, allowing astronomers to trace the growth of the cannibalistic Galaxy.

What is a Red Giant Star?

• It is a luminous star of low or intermediate mass in a late phase of stellar evolution.
• Stellar evolution is the process by which a star changes over the course of time
• Its outer atmosphere is inflated and tenuous making its radius larger than that of the Sun.
• The surface temperature is around 5,000 K.

Key Facts

• A red giant star is a dying star in the last stages of its stellar evolution.
• These stars usually result from low and intermediate-mass main-sequence stars of around 0.5 to 5 solar masses.
• Most of the bright stars are red giants, due to their luminosity.
• Red giant stars are between 100 to 1.000 times more luminous than the Sun.
• Most red giant stars live up to around 0.1 to 2 billion years.
• The stars can have a stable habitable zone, allowing life to probably develop on planets.
• One of the biggest red giants ever discovered is VY Canis Majoris, around 1,400 times bigger than the Sun.

Key Facts on Lithium

• Lithium is an alkali metal.
• It's silver-white in pure form. It has one of the lowest melting points and a high boiling point for a metal.
• Lithium metal burns white, though it imparts a crimson color to a flame.
• Lithium doesn't occur free in nature; it is found in nearly all igneous rocks and in mineral springs.
• It was one of three elements produced by the big bang, along with hydrogen and helium.

Pure lithium metal is corrosive, it can easily react with air and water,

• It is the least dense solid element with a density of about half that of water.
• Lithium is employed in medicine, as a heat transfer agent, for making alloys, and for batteries.
• The transmutation of lithium to tritium was the first man-made nuclear fusion reaction.