Astronomers Identify Early Barred Spiral Galaxy Formed 2 Billion Years After Big Bang
Researchers have confirmed the existence of COSMOS-74706, a barred spiral galaxy that formed approximately 11.5 billion years ago, providing new insights into early galaxy evolution.
Astronomers have identified COSMOS-74706, a barred spiral galaxy that existed about 11.5 billion years ago, just 2 billion years after the Big Bang. This discovery offers new insights into the formation and evolution of galactic structures in the early universe.
The research team, led by Daniel Ivanov, a graduate student in physics and astronomy at the University of Pittsburgh, utilized high-resolution imaging from the James Webb Space Telescope (JWST) and spectroscopic data from the Multi-Object Spectrograph for Infrared Exploration (MOSFIRE) on the Keck I telescope to confirm the galaxy's age and structure. Ivanov noted,
"This galaxy was developing bars two billion years after the birth of the universe."
Stellar bars are elongated features of stars and gas that stretch across the centers of some spiral galaxies, including the Milky Way. They play a significant role in galactic evolution by channeling gas toward the core, potentially fueling supermassive black holes and influencing star formation.
Previous reports have suggested the presence of barred spiral galaxies in earlier periods; however, those findings relied on less precise redshift measurements. In contrast, the identification of COSMOS-74706 was confirmed through spectroscopy, providing more reliable distance data. Ivanov emphasized,
"It's the highest redshift, spectroscopically confirmed, unlensed barred spiral galaxy."
This discovery contributes to understanding the timeline of bar formation in galaxies and suggests that such structures may have emerged earlier than previously thought. The findings were presented at the 247th meeting of the American Astronomical Society.