New observations using the Atacama Large Millimeter/submillimeter Array (ALMA) have identified the sites of star formation and a potential site of star death within a nebula in a galaxy 13.2 billion light-years away. These structures have been observed at the farthest distance yet.
Astronomer Yoichi Tamura of Nagoya University led a team that aimed to make high-resolution observations of MACS0416_Y1, located in the constellation Eridanus, 13.2 billion light-years away. Previous observations by the team had detected radio waves emitted by both oxygen and dust, which are components of interstellar nebulae. However, the resolution was insufficient to study the structure of the nebulae and gain insights into star formation and death.
During this new observation, the team used ALMA for 28 hours to focus on MACS0416_Y1. The results revealed an intricate interconnection between the regions emitting the dust and the regions emitting oxygen. This suggests that newly formed stars within the nebulae ionize the surrounding gas, leading to this pattern.
The team also discovered a massive cavity spanning about 1,000 light-years within the dust-dominated areas. This cavity may be an outcome of successive supernova explosions caused by the birth of many new, massive, and short-lived stars within the nebulae. It could potentially be a superbubble.
Takuya Hashimoto from the University of Tsukuba illustrated the observation performance by stating, “It corresponds to capturing the extremely weak light emitted by two fireflies located 3 centimeters apart on the summit of Mount Fuji as seen from Tokyo, and being able to distinguish between those two fireflies.”
Analysis of the gas motion within the nebulae suggests that this environment is conducive to the formation of multiple stars in massive clusters. Team leader Tamura envisions further insights gained through high-resolution observations of these star clusters themselves, using instruments such as the James Webb Space Telescope and the planned Extremely Large Telescopes.