Abstract
Abstract We report the first evidence of an ongoing collision between two star clusters in our Galaxy, namely IC 4665 and Collinder 350. These are open clusters located at a distance of ∼330 pc from the Sun and ∼100 pc above the Galactic plane, and they both have prograde motions with only a small difference in their velocities (Collinder 350 moves $\sim 5\, \rm {km\, s^{-1}}$ faster than IC 4665); as inferred from ESA/Gaia based catalogue. Interestingly, the two clusters are physically separated by only ∼36 pc in space; a distance that is smaller than the sum of their respective radii. Furthermore, the clusters exhibit signatures of elongated stellar density distributions, and we also detect an onset of an inter-cluster stellar bridge. Moreover, the orbit analysis suggests that the younger cluster IC 4665 (age = 53 Myr) must have formed at a distance >500 pc away from Collinder 350 (age = 617 Myr). These findings together imply that the two clusters do not represent merging of two objects in a binary system; rather, what we are witnessing is an actual collision between two independently formed star clusters. This collision phenomenon provides a unique opportunity to explore new aspects of formation and evolution theory of star clusters.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Monthly Notices of the Royal Astronomical Society: Letters
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
