Cradles and graves of stars are observed in the most distant galaxy ever observed

New observations using the Atacama Large Millimeter/Submillimeter Array (ALMA) have isolated star formation sites and potential star death sites from the surrounding nebula in a galaxy 13.2 billion light-years away. This is the farthest such structure has ever been observed.

A team led by Nagoya University astronomer Yoichi Tamura attempted high-resolution observations of MACS0416_Y1, located 13.2 billion light-years away in the constellation Eridanus. Previous observations of this galaxy by the same team had detected radio waves emitted by oxygen and dust, the two components of the interstellar nebula. Detailed observations of the distribution of dust and oxygen can provide clues about how stars are born and die inside nebulae, but the observations lacked the resolution needed to see the composition of nebulae.

This time zooming in on MACS0416_Y1, the team observed it with ALMA for 28 hours. The results showed that the dust signal regions and the oxygen emission regions are intricately intertwined, avoiding each other, indicating the process of newly formed stars within the nebulae ionizing the surrounding gas.

The team also discovered a massive cavity spanning about 1,000 light-years in the dust-dominated region. When many new, massive, short-lived stars are born together, successive supernova explosions create huge “superbubbles” in nebulae. Discovered cavity can certainly be such a superbubble.

These observational results were published in the title “300 pc resolution imaging of the As = 8.31 galaxy: Turbulent ionized gas and stellar feedback 600 million years after the Big Bang”. The Astrophysical Journal.

Takuya Hashimoto of the University of Tsukuba describes the observational performance as follows: “It corresponds to capturing the very weak light emitted by two flames located 3 centimeters apart on the summit of Mount Fuji as seen from Tokyo, and distinguishing between them. Fireflies.”

Measurements of the motion of the gas in nebulae indicate an atmosphere where many stars have joined together to form massive clusters. Team leader Tamura explains, “High-resolution observations of these star clusters with instruments such as the James Webb Space Telescope and the planned Extremely Large Telescopes will yield more detailed information in the future.”