Star Cradles and Graves in the Farthest Galaxy Ever Seen

July 14 () –

Observations with the ALMA telescope have distinguished star formation sites and a possible stellar death site from the surrounding nebula. in a galaxy 13.2 billion light years away.

This is the farthest such structures have been observed, according to the team that made the finding, led by Yoichi Tamura, an astronomer at Nagoya University, who publish results in The AstrophysicalJournal.

The researchers harnessed the power of the Atacama Large Millimeter/submillimeter Array (ALMA) to make high-resolution observations of MACS0416-Y1, located 13.2 billion light-years away (600 million light-years after the Big Bang) in the constellation Eridanus.

Previous observations of this galaxy by the same team had detected radio waves emitted by both oxygen and dust, two components of interstellar nebulae. Detailed observations of the distribution of dust and oxygen can provide clues about how stars are born and die within nebulae, but the observations lacked the resolution needed to see the structure of the nebulae.

This time, the team observed with ALMA for 28 hours and zoomed in on MACS0416-Y1. The results showed that the dust signal regions and the oxygen emission regions are intricately intertwined, avoiding each other, suggesting the process in which newly formed stars within nebulae ionize the surrounding gas.

In addition, the team found a massive cavity spanning approximately 1,000 light-years in regions dominated by dust. When many new, massive, short-lived stars are born together, the resulting successive supernova explosions create huge “superbubbles” in the nebulae. In fact, the uncovered cavity may be such a super bubble.

LIKE TWO FIREFLIES ON MOUNT FUJI VIEWED FROM TOKYO

Takuya Hashimoto of Tsukuba University describes the observation performance as follows: “It corresponds to capturing the extremely weak light emitted by two fireflies located 3 centimeters apart on top of Mount Fuji as seen from Tokyo, and be able to distinguish between those two fireflies“.

Measurements of the movement of gas in the nebulae indicate an environment in which many stars can form together as massive clusters. The team leader, Tamura, explains it’s a statement: “In the future, more detailed information may be obtained by making high-resolution observations of these star clusters, using instruments such as the James Webb Space Telescope and the planned Extremely Large Telescopes.”