Astronomers have conducted a comprehensive study utilizing a blend of new observations and archival data to uncover the ages and masses of star clusters within tidal tails. Their findings unveil the remarkably young age of these clusters, estimated to be a mere 10 million years old, and shed light on their consistent formation rate along tails spanning thousands of light-years.
Associate Professor Sanchayeeta Borthakur, an expert in extragalactic astronomy at ASU’s School of Earth and Space Exploration, emphasizes the significance of these observations in elucidating the mechanisms behind star formation. The stretching of galaxy spiral arms into tidal tails, resembling taffy pulled by gravitational interactions between galaxies, serves as a compelling visual representation of this phenomenon.
Prior to galactic mergers, dusty clouds of molecular hydrogen pervaded the galaxies, remaining relatively inert. However, interactions during mergers led to the compression of these hydrogen clouds, triggering intense episodes of star formation akin to a “firestorm.” The fate of these star clusters within the tidal tails remains uncertain, with possibilities ranging from evolving into globular star clusters to dispersing and forming halos around their host galaxies.
Assistant Teaching Professor Karen Knierman reflects on the extensive duration of the project, spanning over two decades and involving data from various epochs of the Hubble Space Telescope, alongside contributions from other observatories. The research underscores the prevalence of “string-of-pearls” star formation in tidal tails, suggesting its potential commonality in the early universe during frequent galaxy collisions.
The abundance of young objects within the tidal tails offers insights into the efficiency of cluster formation processes. This phenomenon provides a glimpse into the past, as nearby galaxies observed by the Hubble serve as proxies for understanding galactic evolution in distant epochs.
In conclusion, the study illuminates the dynamic processes shaping galactic interactions and star formation, offering valuable insights into the evolution of galaxies and their constituent star clusters.
