DWARF SPHEROIDAL GALAXY Meaning and
Definition
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A dwarf spheroidal galaxy is a small and faint type of galaxy that is commonly found orbiting larger galaxies, such as the Milky Way. These galaxies are characterized by their round or elliptical shape and a lack of spiral arms or a distinct disk structure. Dwarf spheroidal galaxies typically have a low mass and a relatively high proportion of dark matter.
Measuring only a few thousand light-years in diameter, dwarf spheroidal galaxies are among the smallest galaxies known in the universe. They contain a small number of stars, ranging from a few hundred thousand to a few million, and have a much lower luminosity compared to larger galaxies. The stars within these galaxies are generally older and less metal-rich than those found in larger galaxies.
The term "dwarf" refers to their size and mass, as they are much smaller and less massive than other types of galaxies. "Spheroidal" describes their shape, which is often round or elongated like a sphere. Due to their faintness and small size, dwarf spheroidal galaxies were discovered relatively recently, and advanced telescopes and techniques have aided in their detection and study.
Dwarf spheroidal galaxies play a crucial role in our understanding of galaxy formation and evolution. Scientists study these galaxies to gain insights into the properties of dark matter, stellar populations, and the environmental effects of larger galaxies on smaller satellite systems. The study of dwarf spheroidal galaxies provides valuable data for testing and refining theories about the structure and dynamics of the universe.
