Giant 'dragon cloud' may solve mystery of how massive stars form

Understanding how massive stars form has been a long-standing topic of debate for astrophysicists, especially given the lack of observations necessary to build reliable theories.

Massive stars are relatively rare, so they are difficult to spot during the formation process. But new observations of the so-called "dragon cloud" may hold the key to answering this mystery.

A team of astronomers used the ALMA telescope in the Atacama Desert in northern Chile to study the Dragon Cloud, a dense cloud of molecular hydrogen that serves as a site for star formation throughout its complex.

And astronomers were looking specifically for dust, which along with the gas that makes up the bulk of the complex collapses to form stars.

Astronomers found several regions of active star formation, but also a strangely dense cluster that lacked any newborn stars at all. Upon further investigation, the team discovered that the central block was in fact made up of two separate areas. One region contained more than 30 solar masses of material, while the other contained only 2 solar masses of material.

According to their observations, these clumps were very dense and severely collapsed, which means that these clumps will soon start forming stars.

More importantly, the astronomers found that the clumps themselves did not appear to break apart into smaller clumps when they collapsed. This leads to the "primary accretion" model of star formation. In this model, the most massive stars collapse from single units of gas clouds and actually begin their lives at incredibly high masses.

Observations support this idea because, for the first time, scientists have been able to observe a giant cloud of gas collapsing directly without separating.

Astronomers called for more detailed observations of the compound in order to progress in deciphering the mystery of the formation of massive stars.

The results have been published in the arXiv preprint.