open clusters (OCs) tagged posts

Using the Hubble Space Telescope (HST), astronomers have observed a supermassive galactic open cluster designated Westerlund 1. Results of the study, published Jan. 28 on the pre-print server arXiv, yield essential details regarding the structure of this cluster.

Open clusters (OCs), formed from the same giant molecular cloud, are groups of stars loosely gravitationally bound to each other. It is assumed that most star formation takes place in massive clusters of stars, known as superstar clusters (SSCs). They are very massive young OCs usually containing a very large number of young, massive stars. The total mass of a typical SSC exceeds 10,000 solar masses.

Westerlund 1 is a supermas...

An image of Camargo 791, one of the newly found embedded clusters. Credit: Camargo et al.

When a giant cloud of molecular gas condenses, star clusters are born. It may sound simple but the formation of star clusters is a very complex process. By peering into this process we could get valuable information on the evolution of galaxies and improve our knowledge about large cosmic structures in the universe. “Star clusters are often considered as building blocks of galaxies. Understanding how these objects form and evolve is vital to our comprehension of the structure, formation and evolution of galaxies,” Denilso Camargo.

Camargo and his colleagues recently discovered a multitude of star clusters using NASA’s Wide-field Infrared Survey Explorer: 652 star clusters, stellar groups and candidate...