From UPSC perspective, the following things are important :
Prelims level : Explaining the increase of Li in the the Universe
Mains level : Not much
In a study recently published in Nature Astronomy scientists from Indian Institute of Astrophysics (IIA) along with their international collaborators have provided a robust observational evidence for the first time that Li production is common among low mass Sun-like stars during their He-core burning phase.
Importance of lithium in our life
- Light inflammable, metal lithium (Li) has brought about transformation in modern communication devices and transportation.
- A great deal of today’s technology is powered by lithium in its various shades [remember Li-ion battery!].
- But where does the element come from?
- The origin of much of the Li can be traced to a single event, the Big-Bang that happened about 13.7 Billion years ago, from which the present-day Universe was also born.
Why lithium was thought to be different?
- Li content in the physical Universe has increased by about a factor of four over the life of the Universe.
- However, the rest of the elements carbon, nitrogen, oxygen, iron, nickel and so on which grew about a million times over the lifetime of the Universe.
- Li, however, understood to be an exemption!
- Current understanding is that lithium in stars like our Sun only gets destroyed over their lifetime.
- As a matter of fact, the composition of all the elements in the Sun and the Earth is similar.
- But, the measured content of Li in the Sun is a factor of 100 lower than that of the Earth, though both are known to have formed together.
So, what the new finding suggests?
- This discovery challenges the long-held idea that stars only destroy lithium during their lifetime.
- It implies that the Sun itself will manufacture lithium in the future.
- This is not predicted by models, indicating that there is some physical process missing in stellar theory.
- Further, the authors identified “He flash”.
- “He flash” is an on-set of He-ignition at the star’s core via violent eruption at the end of the star’s core hydrogen-burning phase, as the source of Li production.
- Our Sun will reach this phase in about 6-7 billion years.