A breakthrough has been made in astronomical observations using the Atacama Large Millimeter/submillimeter Array (ALMA). Researchers led by Yoichi Tamura from Nagoya University have successfully identified the sites of star formation and a potential location of star death within a distant galaxy, located 13.2 billion light-years away in the constellation Eridanus. This remarkable achievement represents the farthest distance at which such structures have been observed.
Previous studies conducted by the same team had detected radio waves emitted by oxygen and dust, which are key components of interstellar nebulae, in the galaxy MACS0416_Y1. However, the resolution of those observations was insufficient to reveal the detailed structure of the nebulae. To overcome this limitation, the team utilized ALMA and carried out high-resolution observations of MACS0416_Y1 for a duration of 28 hours.
The results of the observations unveiled a fascinating relationship between the dust signal regions and oxygen emission regions. These two components were found to be intricately intertwined but avoided direct overlap, indicating a process in which newly formed stars within the nebulae ionize the surrounding gas.
In addition to this discovery, the researchers identified a massive cavity spanning around 1,000 light-years within the dust-dominated regions of the galaxy. Such cavities are believed to be formed by the collective effect of multiple supernova explosions resulting from the birth and subsequent death of numerous massive stars within the nebulae. The enormous size of this cavity suggests that it may indeed be a superbubble formed by these explosive events.
The findings from this study were published in The Astrophysical Journal under the title “The 300 pc Resolution Imaging of a z = 8.31 Galaxy: Turbulent Ionized Gas and Potential Stellar Feedback 600 Million Years after the Big Bang.” Takuya Hashimoto, a researcher from the University of Tsukuba, compared the observation performance to the ability to detect the faint light emitted by two fireflies located just 3 centimeters apart on the summit of Mount Fuji from the vantage point of Tokyo, illustrating the extraordinary precision achieved.
The measurements of gas motion within the nebulae indicate an environment conducive to the formation of multiple stars within massive clusters. Tamura, the leader of the research team, expressed optimism about future investigations using advanced instruments like the James Webb Space Telescope and the upcoming Extremely Large Telescopes, which will provide even more detailed information about these star clusters themselves.
Source: National Astronomical Observatory of Japan