Binary Star Clues Reveal a Sharper Age for Star Cluster NGC 7789

Yakut and collaborators use six well-measured binary systems in NGC 7789 to derive a precise, physically grounded cluster age. By combining radial velocities, TESS light curves, and multiwavelength SEDs, they determine an age of 1.26 ± 0.09 Gyr, an extinction of Aᵥ = 0.90, and confirm cluster membership through Gaia astrometry. Their binary-based method overcomes common photometric uncertainties and provides a consistent framework for studying stellar evolution.