A possible massive-star embryo has an intriguing combination of features that includes an exceptionally compact center, a vast surrounding reservoir of cold gas and dust, and no convincing signs of energetic outflows. 

Nicknamed the ‘dragon egg,’ this object could offer a rare look at how massive stars begin forming. The researchers describe it as “a promising compact high-mass core candidate” in their study.

However, astronomers still cannot tell how much mass is concentrated in its tiny core—or whether a protostar has already formed. This makes the object particularly interesting because scientists still debate how stars with at least eight times the Sun’s mass take shape.

One theory proposes that a massive core assembles first and collapses into a star. Another suggests that a smaller seed grows by drawing in material from the surrounding cloud. 

By revealing the structure of a possible early-stage object, the dragon egg could help researchers investigate these competing ideas.

The dragon egg, designated C2c1a, lies in an infrared-dark cloud called Dragon Cloud, about 16,300 light-years from Earth. Its parent clump contains around 1,061 solar masses but emits little energy relative to its mass, a sign that it may be at an early stage of massive-star formation.

Earlier observations suggested that C2c1a contained 20 to 30 solar masses, but they could not establish how tightly that mass was concentrated or whether a protostar had formed. 

3 millimeters.

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