Context:
Astronomers recently discovered five young star clusters, and possibly the oldest star clusters ever, born from the time when the Universe was an infant.
Relevance:
Facts for Prelims
About Star Clusters:
- Definition: A star cluster consists of stellar groups held together by the mutual gravitational attraction of its members, which share a common origin.
- Importance: Star clusters are vital for astronomers to study and model stellar evolution and ages.
- Categories: There are two main types of stellar clusters: open clusters (also known as galactic clusters) and globular clusters.
Open (Galactic) Clusters:
- Characteristics:
- Named because their individual component stars are easily resolved through a telescope.
- Often located on the dusty spiral arms of spiral galaxies.
- Stars in an open cluster originate from the same initial giant molecular cloud.
- They contain from a dozen to many hundreds of stars, usually arranged unsymmetrically.
Globular Clusters:
- Characteristics:
- Comprise several thousand to one million stars in a spherical, gravitationally-bound system.
- Mostly located in the halo surrounding the galactic plane, containing the oldest stars in the galaxy.
- There is little free dust or gas, so no new star formation occurs.
- Stellar densities within the inner regions are very high compared to regions around the Sun.
Associations:
- Definition: Groups made up of a few dozen to hundreds of stars of similar type and common origin, with a density in space lower than that of the surrounding field, are also recognized as associations.
-Source: Indian Express
