Protoplanetary Disk Found Outside Milky Way: A Breakthrough

In an unprecedented scientific breakthrough, researchers have unearthed a protoplanetary disk encircling a nascent star nestled within the Large Magellanic Cloud, a neighboring galaxy to the Milky Way. This pivotal detection marks the first instance of a protoplanetary disk, akin to those instrumental in planet formation within our galaxy, being discovered beyond the confines of the Milky Way.

Artistic representation of the protoplanetary disks of TW Hydrae. Credit: NASA, ESA, J. Debes STScI

These recent revelations shed light on a burgeoning, colossal star accreting and assimilating matter from its adjacent environment, thereby leading to the formation of a rotating protoplanetary disk. This monumental discovery was made possible through the powerful Atacama Large Millimeter/submillimeter Array (ALMA) housed in Chile, an integral partner of the European Southern Observatory (ESO).

The research builds upon prior observations conducted with the Multi Unit Spectroscopic Explorer (MUSE) apparatus, an essential component of ESO's Very Large Telescope (VLT). This device detected a jet emanating from a star in the process of formation, a system christened HH 1177, nestled deep within a gaseous cloud in the Large Magellanic Cloud. 

As matter gravitates towards this accreting star, it doesn't plunge directly onto the star, instead, it forms a flat, rapidly rotating disk around the star. The disk spins more swiftly as it nears the center, and this disparity in speed provides undeniable proof of an accretion disk's existence. 

Utilizing the precise frequency measurements from ALMA, the team could discern the distinct rotation of a disk, thereby validating the discovery of the first disk surrounding a young star outside our galaxy.

Massive stars such as the one observed, develop at a faster pace and have a shorter lifespan compared to low-mass stars like our Sun. Observing these massive stars within our galaxy is notoriously challenging as they are often veiled by the dust from which they originate. However, the Large Magellanic Cloud, located approximately 160,000 light-years from us, offers an unobstructed view of star and planet formation thanks to its lower dust content.

"We are witnessing an era of accelerated technological progress in astronomical tools," concludes McLeod. "The ability to study stellar formation at such immense distances and beyond our galaxy is truly exhilarating."