Astronomers have, for the first time, discovered a disc of gas and dust around a young star in another galaxy, describing it as a “special moment”.
An international team of experts led by Durham University reported the detection of the star and its rotating disc structure outside the Milky Way, around 163,000 light years from Earth.
Located in the neighbouring galaxy called the Large Magellanic Cloud, the event was observed in a region known as N180 – where many other new stars are actively forming.
The structure is known as the accretion disc – which is formed by material such as gas, dust, and other debris gradually being drawn towards the growing star due to gravitational forces.
The event, reported in the journal Nature, was detected using the Atacama Large Millimetre/submillimetre Array (Alma) in Chile.
Lead author Dr Anna McLeod, from the Centre for Extragalactic Astronomy at Durham University, said: “When I first saw evidence for a rotating structure in the Alma data, I could not believe that we had detected the first extragalactic accretion disc; it was a special moment.
“We know discs are vital to forming stars and planets in our galaxy, and here, for the first time, we’re seeing direct evidence for this in another galaxy.”
The astronomers managed to find evidence of this disc by measuring the movement of the dense gas around the star.
The disc rotates faster closer to the centre than the outer edge and researchers say this difference in speed is the “smoking gun” that confirms the presence of an accretion disc.
Being able to study how stars form at such incredible distances and in a different galaxy is very exciting.— Dr Anna McLeod
The star is thought to be massive, around 15 times the mass of the Sun.
Researchers say massive stars can be challenging to observe in the Milky Way and are often obscured from view by the dusty material surrounding them.
However, the material from which new stars are born in the Large Magellanic Cloud is fundamentally different from that in the Milky Way, allowing astronomers an unobstructed view of star formation.
The team said studying star and disc formation across different galactic environments will help astronomers understand more about how stars are formed.
Dr McLeod said: “Being able to study how stars form at such incredible distances and in a different galaxy is very exciting.”
