what are its exotic components?
Some exotic classes of stars, such as "blue stragglers", "millisecond pulsars", and "low-mass X-ray binaries", are much more common in globular clusters.
Globular cluster
 Due to these chance encounters, some exotic classes of stars, such as "blue stragglers", "millisecond pulsars", and "low-mass X-ray binaries", are much more common in globular clusters. 
some globular clusters have three main sequence tracks. this indicates UNANSWERABLE what is this cluster? It is a spherical collection of stars that orbits a galactic core. how is this clusters formed? The formation of globular clusters remains a poorly understood phenomenon and it remains uncertain whether the stars in a globular cluster form in a single generation or are spawned across multiple generations over a period of several hundred million years. what are this composed of? Globular clusters are generally composed of hundreds of thousands of low-metal, old stars.
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Globular cluster [SEP] Exotic components
Globular clusters have a very high star density, and therefore close interactions and near-collisions of stars occur relatively often. Due to these chance encounters, some exotic classes of stars, such as "blue stragglers", "millisecond pulsars", and "low-mass X-ray binaries", are much more common in globular clusters. A “blue straggler” is thought to form from the merger of two stars, possibly as a result of an encounter with a binary system. The resulting star has a higher temperature than comparable stars in the cluster with the same luminosity, and thus differs from the main sequence stars formed at the beginning of the cluster.