NGC 6864 vs. NGC 6229: Dueling Blue Straggler Populations

NGC 6864 vs. NGC 6229: Dueling Blue Straggler Populations

Blue stragglers are stars within a globular cluster that lie along an extension of the main-sequence, above the turnoff point. As such they appear to be much younger than the rest of their stellar population. Current research suggests that they form by coalescence of mass-transfer between two companions in a binary system and the merger of two stars induced by stellar collision. By observing the population distributions of blue stragglers in globular clusters we can learn about the mechanisms through which they formed and the evolutionary dynamics of the cluster itself.