Accretion disc detected in another galaxy for the first time
29 Nov 2023



Using ALMA scientists have observed an accretion disc in the Large Magellanic Cloud.

Artist’s impression of the disc and jet in the young star system HH 1177

It's the first time this type of disc, just like those which formed the stars in our own Milky Way, has ever been found outside our Galaxy. The new observations reveal a massive young star in the HH 1177 system, drawing in matter from its surroundings to form a rotating disc. It was detected using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, in which the European Southern Observatory (ESO) is a partner.

Accretion discs are a crucial early stage in the formation of solar systems. As gas and dust stream in to form a star and its planetary system, it flattens into this type of structure.

“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," says Dr Anna McLeod, an associate professor at Durham University and lead author of the study published in Nature. “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 detailed frequency measurements from ALMA allowed scientists to distinguish the characteristic spin of a disc, confirming the detection of the first disc around an extragalactic young star.

“The significance of discs in the creation of stars and planets within our galaxy is well-established. However, observing direct evidence of this phenomenon in another galaxy is an amazing first for astronomy," added Dr Pamela Klaassen, an astronomer at UK ATC and co-author on this paper. “The opportunity to examine the first steps in the creation of other solar systems opens up new areas of study and understanding when it comes to the formation of planets and galaxies." 

Find out more.

Read the paper in Nature.​