• Massive warm ring reveals unusual behavior in newborn stars
• Findings shed light on magnetic energy’s role in star formation

Japanese scientists observed a newborn star inside a dense gas and dust cloud “sneezing,” releasing bursts of energy that may help explain how stars like the Sun form.

In a study published Thursday in The Astrophysical Journal Letters, researchers from Kyushu and Kagawa Universities reported that the young star, surrounded by a dense gas and dust disk, expelled material in a way that formed a massive warm ring about 1,000 astronomical units wide—much larger than similar structures previously observed.

The team said the discovery provides a clearer look at the earliest stages of star formation, which are usually hard to observe directly because newborn stars are often hidden in thick gas clouds.

“Thanks to ALMA telescopes in Chile, we can see the different materials forming stellar nurseries,” said Masahiro Machida, Kyushu University professor and lead author.

Using ALMA, the team studied a very young protostar in the nearby Taurus Molecular Cloud. While the Sun is around 4.6 billion years old, this star is less than 100,000 years old.

Earlier research by the same group had identified smaller, needle-like structures about 10 astronomical units wide linked to magnetic activity, described as “sneezes” that release energy from forming stars. The newly observed ring appears to be a much larger version of this process.

“Our data show this warm ring is slightly hotter than its surroundings and likely produced by a magnetic field threading the protostellar disk,” said Kazuki Tokuda from Kagawa University. “It supports our hypothesis that newborn stars undergo dynamic magnetic-gas redistribution right after birth, generating shock waves that heat surrounding gas.”

Machida explained that “sneezing” describes how material is suddenly ejected outward, similar to a human sneeze, helping the star release built-up magnetic energy.

Magnetic fields are critical for star formation. Without a mechanism to release excess magnetic energy, stars would struggle to form under realistic conditions.

Newborn stars are also known to drive strong bipolar outflows, sometimes called their “first cry,” but the study suggests they may also experience intermittent “sneezing” events.

The findings could also influence our understanding of planet formation, as the gas and dust disk around a young star is where planets form, and changes in this environment may affect planetary system evolution.

The team plans to continue observing similar systems and comparing results with computer simulations. Not all newborn stars show this behavior, but it appears increasingly common.

“These results highlight that star formation is a highly dynamic process, not only steady accumulation but also intermittent energetic events,” Machida said. “Understanding these processes is essential for a complete picture of how stars and planetary systems form.”