What is galaxy? »Its Definition and Meaning [2019]

It is a conglomerate of planets , millions of stars, dark meter , clouds formed of gas, cosmic dust and energy that are united thanks to the force of In addition to this, these elements are orbiting around a point where it is believed that a black hole may exist, the number of stellar elements that make up a specific galaxy is uncountable regardless of size of it, other elements that make it up are multiple star systems, nebulae and star clusters.

All those star bodies (including the Sun) that can be observed simply from anywhere in The face of the Earth , belong to the so-called Via Lactea , according to experts, this consists of a size of 1012 spiral-shaped solar masses, its diameter is one Approximate size of 1.42 × 1018 km and the star number s that make it up exceeds 200 billion, the milky way in turn is part of a set of galaxies which are called as Local Group.

The galaxies They can have different forms , among them we can mention the lenticular, elliptic, irregular and spirals.

• Lenticular Galaxies: These are considered as a spice of transformation between spiral-shaped and elliptical galaxies, are formed by a large envelope , a disk and a central condensation of great relevance, this type of galaxy is composed of three subcategories, SO1, SO2, SO3.
• Elliptical Galaxies: so called since its shape is similar to that of an ellipse, are classified from 0 to 7 the number seven being the most oval possible, they have little stellar matter and therefore few open clusters, so s u ability to produce stars is very low.
• Irregular Galaxies: By not having an elliptical or spiral shape they do not enter the Hubble classification so they are called irregular, these are subdivided into two types the Irr-I that have a structure not clear enough to enter the Hubble classification, the other type is the Irr-II unlike the former have no form that can enter the classification.
• Spiral Galaxies: are disk-shaped structures made up of interstellar matter and stars that are constantly rotating.