Stars' 'DNA' could help scientists find Sun's lost siblings
Sydney, April 18: With the aim to find the lost siblings of the Sun, now scattered across the sky, a team of astronomers has collected the "DNA" of more than 340,000 stars in the Milky Way.
The "DNA" can help trace the ancestry of stars, showing astronomers how the universe went from having only hydrogen and helium -- just after the Big Bang -- to being filled today with all the elements we have here on Earth that are necessary for life.
The research, detailed in the journal Monthly Notices of the Royal Astronomical Society, is based on the Galactic Archaeology survey, called GALAH, launched in late 2013 as part of a quest to uncover the formulation and evolution of galaxies.
When complete, GALAH will investigate more than a million stars.
The GALAH survey used the HERMES spectrograph at the Australian Astronomical Observatory's (AAO) 3.9-metre Anglo-Australian Telescope near Coonabarabran in New South Wales to collect spectra for the 340,000 stars.
"No other survey has been able to measure as many elements for as many stars as GALAH," said Gayandhi De Silva of the University of Sydney and AAO.
"This data will enable such discoveries as the original star clusters of the Galaxy, including the Sun's birth cluster and solar siblings -- there is no other dataset like this ever collected anywhere else in the world," De Silva said.
The Sun, like all stars, was born in a group or cluster of thousands of stars, explained Sarah Martell from the University of New South Wales (UNSW) Sydney who leads the GALAH survey observations.
"Every star in that cluster will have the same chemical composition, or DNA - these clusters are quickly pulled apart by our Milky Way Galaxy and are now scattered across the sky," Martell said.
"The GALAH team's aim is to make DNA matches between stars to find their long-lost sisters and brothers," she added.
For each star, this DNA is the amount they contain of each of nearly two dozen chemical elements such as oxygen, aluminium and iron.
Unfortunately, astronomers cannot collect the DNA of a star with a mouth swab but instead use the starlight, with a technique called spectroscopy.
The light from the star is collected by the telescope and then passed through an instrument called a spectrograph, which splits the light into detailed rainbows, or spectra.
Let the Truth be known. If you read VB and like VB, please be a VB Supporter and Help us deliver the Truth to one and all.
Lt Gen NS Raja Subramani to be India's next Chief of Defence Staff
New Delhi (PTI): Lt Gen NS Raja Subramani will be India's new Chief of Defence Staff (CDS) and his key task is set to be to implement the ambitious theaterisation plan that seeks to ensure tri-services synergy.
He will succeed Gen Anil Chauhan whose tenure will come to an end on May 30.
Gen Chauhan, a former Eastern Army Commander, took charge as the country's senior-most military commander in September 2022, over nine months after the first CDS, General Bipin Rawat, died in a helicopter crash in Tamil Nadu.
The government has appointed Lt Gen NS Raja Subramani (Retd) as the Chief of Defence Staff, who will also function as the secretary of the Department of Military Affairs, the defence ministry said on Saturday.
Lt Gen Subramani is currently serving as the military adviser to the National Security Council Secretariat.
Prior to that, he was the Vice Chief of the Army Staff from July 1, 2024 to July 31, 2025, and was General Officer Commanding-in-Chief of the Central Command from March 2023 till June 2024.
As Chief of Defence Staff, Lt Gen Subramani's primary task will be to implement the theaterisation model to bring in tri-services synergy by rolling out integrated military commands.
The officer is a graduate of the National Defence Academy and the Indian Military Academy. He was commissioned into the eighth battalion of the Garhwal Rifles on December 14, 1985.
Lt Gen Subramani is an alumnus of Joint Services Command Staff College, Bracknell (UK), and the National Defence College, New Delhi. He holds a Master of Arts degree from King's College London and an MPhil in defence studies from Madras University.
In his illustrious career spanning over 40 years, Lt Gen Subramani has served across a wide spectrum of conflict and terrain profiles and tenanted a host of Command, Staff and Instructional appointments.
He commanded the 16 Garhwal Rifles in Counter-Insurgency operations in Assam as part of Operation Rhino, the 168 Infantry Brigade in Jammu and Kashmir, and the 17 Mountain Division in the Central Sector, all during a challenging operational environment.
He also has the distinction of commanding two Corps, including the Indian Army's premier strike Corps on the Western Front.
